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imgui.h (124730B)


      1 // dear imgui, v1.50
      2 // (headers)
      3 
      4 // See imgui.cpp file for documentation.
      5 // See ImGui::ShowTestWindow() in imgui_demo.cpp for demo code.
      6 // Read 'Programmer guide' in imgui.cpp for notes on how to setup ImGui in your codebase.
      7 // Get latest version at https://github.com/ocornut/imgui
      8 
      9 #pragma once
     10 
     11 #if !defined(IMGUI_DISABLE_INCLUDE_IMCONFIG_H) || defined(IMGUI_INCLUDE_IMCONFIG_H)
     12 #include "imconfig.h"       // User-editable configuration file
     13 #endif
     14 #include <float.h>          // FLT_MAX
     15 #include <stdarg.h>         // va_list
     16 #include <stddef.h>         // ptrdiff_t, NULL
     17 #include <string.h>         // memset, memmove, memcpy, strlen, strchr, strcpy, strcmp
     18 
     19 #define IMGUI_VERSION       "1.50"
     20 
     21 // Define attributes of all API symbols declarations, e.g. for DLL under Windows.
     22 #ifndef IMGUI_API
     23 #define IMGUI_API
     24 #endif
     25 
     26 // Define assertion handler.
     27 #ifndef IM_ASSERT
     28 #include <assert.h>
     29 #define IM_ASSERT(_EXPR)    assert(_EXPR)
     30 #endif
     31 
     32 // Some compilers support applying printf-style warnings to user functions.
     33 #if defined(__clang__) || defined(__GNUC__)
     34 #define IM_PRINTFARGS(FMT) __attribute__((format(printf, FMT, (FMT+1))))
     35 #else
     36 #define IM_PRINTFARGS(FMT)
     37 #endif
     38 
     39 #if defined(__clang__)
     40 #pragma clang diagnostic push
     41 #pragma clang diagnostic ignored "-Wold-style-cast"
     42 #endif
     43 
     44 // Forward declarations
     45 struct ImDrawChannel;               // Temporary storage for outputting drawing commands out of order, used by ImDrawList::ChannelsSplit()
     46 struct ImDrawCmd;                   // A single draw command within a parent ImDrawList (generally maps to 1 GPU draw call)
     47 struct ImDrawData;                  // All draw command lists required to render the frame
     48 struct ImDrawList;                  // A single draw command list (generally one per window)
     49 struct ImDrawVert;                  // A single vertex (20 bytes by default, override layout with IMGUI_OVERRIDE_DRAWVERT_STRUCT_LAYOUT)
     50 struct ImFont;                      // Runtime data for a single font within a parent ImFontAtlas
     51 struct ImFontAtlas;                 // Runtime data for multiple fonts, bake multiple fonts into a single texture, TTF font loader
     52 struct ImFontConfig;                // Configuration data when adding a font or merging fonts
     53 struct ImColor;                     // Helper functions to create a color that can be converted to either u32 or float4
     54 struct ImGuiIO;                     // Main configuration and I/O between your application and ImGui
     55 struct ImGuiOnceUponAFrame;         // Simple helper for running a block of code not more than once a frame, used by IMGUI_ONCE_UPON_A_FRAME macro
     56 struct ImGuiStorage;                // Simple custom key value storage
     57 struct ImGuiStyle;                  // Runtime data for styling/colors
     58 struct ImGuiTextFilter;             // Parse and apply text filters. In format "aaaaa[,bbbb][,ccccc]"
     59 struct ImGuiTextBuffer;             // Text buffer for logging/accumulating text
     60 struct ImGuiTextEditCallbackData;   // Shared state of ImGui::InputText() when using custom ImGuiTextEditCallback (rare/advanced use)
     61 struct ImGuiSizeConstraintCallbackData;// Structure used to constraint window size in custom ways when using custom ImGuiSizeConstraintCallback (rare/advanced use)
     62 struct ImGuiListClipper;            // Helper to manually clip large list of items
     63 struct ImGuiContext;                // ImGui context (opaque)
     64 
     65 // Typedefs and Enumerations (declared as int for compatibility and to not pollute the top of this file)
     66 typedef unsigned int ImU32;         // 32-bit unsigned integer (typically used to store packed colors)
     67 typedef unsigned int ImGuiID;       // unique ID used by widgets (typically hashed from a stack of string)
     68 typedef unsigned short ImWchar;     // character for keyboard input/display
     69 typedef void* ImTextureID;          // user data to identify a texture (this is whatever to you want it to be! read the FAQ about ImTextureID in imgui.cpp)
     70 typedef int ImGuiCol;               // a color identifier for styling       // enum ImGuiCol_
     71 typedef int ImGuiStyleVar;          // a variable identifier for styling    // enum ImGuiStyleVar_
     72 typedef int ImGuiKey;               // a key identifier (ImGui-side enum)   // enum ImGuiKey_
     73 typedef int ImGuiColorEditMode;     // color edit mode for ColorEdit*()     // enum ImGuiColorEditMode_
     74 typedef int ImGuiMouseCursor;       // a mouse cursor identifier            // enum ImGuiMouseCursor_
     75 typedef int ImGuiWindowFlags;       // window flags for Begin*()            // enum ImGuiWindowFlags_
     76 typedef int ImGuiSetCond;           // condition flags for Set*()           // enum ImGuiSetCond_
     77 typedef int ImGuiInputTextFlags;    // flags for InputText*()               // enum ImGuiInputTextFlags_
     78 typedef int ImGuiSelectableFlags;   // flags for Selectable()               // enum ImGuiSelectableFlags_
     79 typedef int ImGuiTreeNodeFlags;     // flags for TreeNode*(), Collapsing*() // enum ImGuiTreeNodeFlags_
     80 typedef int (*ImGuiTextEditCallback)(ImGuiTextEditCallbackData *data);
     81 typedef void (*ImGuiSizeConstraintCallback)(ImGuiSizeConstraintCallbackData* data);
     82 
     83 // Others helpers at bottom of the file:
     84 // class ImVector<>                 // Lightweight std::vector like class.
     85 // IMGUI_ONCE_UPON_A_FRAME          // Execute a block of code once per frame only (convenient for creating UI within deep-nested code that runs multiple times)
     86 
     87 struct ImVec2
     88 {
     89     float x, y;
     90     ImVec2() { x = y = 0.0f; }
     91     ImVec2(float _x, float _y) { x = _x; y = _y; }
     92 #ifdef IM_VEC2_CLASS_EXTRA          // Define constructor and implicit cast operators in imconfig.h to convert back<>forth from your math types and ImVec2.
     93     IM_VEC2_CLASS_EXTRA
     94 #endif
     95 };
     96 
     97 struct ImVec4
     98 {
     99     float x, y, z, w;
    100     ImVec4() { x = y = z = w = 0.0f; }
    101     ImVec4(float _x, float _y, float _z, float _w) { x = _x; y = _y; z = _z; w = _w; }
    102 #ifdef IM_VEC4_CLASS_EXTRA          // Define constructor and implicit cast operators in imconfig.h to convert back<>forth from your math types and ImVec4.
    103     IM_VEC4_CLASS_EXTRA
    104 #endif
    105 };
    106 
    107 // ImGui end-user API
    108 // In a namespace so that user can add extra functions in a separate file (e.g. Value() helpers for your vector or common types)
    109 namespace ImGui
    110 {
    111     // Main
    112     IMGUI_API ImGuiIO&      GetIO();
    113     IMGUI_API ImGuiStyle&   GetStyle();
    114     IMGUI_API ImDrawData*   GetDrawData();                              // same value as passed to your io.RenderDrawListsFn() function. valid after Render() and until the next call to NewFrame()
    115     IMGUI_API void          NewFrame();                                 // start a new ImGui frame, you can submit any command from this point until NewFrame()/Render().
    116     IMGUI_API void          Render();                                   // ends the ImGui frame, finalize rendering data, then call your io.RenderDrawListsFn() function if set.
    117     IMGUI_API void          Shutdown();
    118     IMGUI_API void          ShowUserGuide();                            // help block
    119     IMGUI_API void          ShowStyleEditor(ImGuiStyle* ref = NULL);    // style editor block. you can pass in a reference ImGuiStyle structure to compare to, revert to and save to (else it uses the default style)
    120     IMGUI_API void          ShowTestWindow(bool* p_open = NULL);        // test window demonstrating ImGui features
    121     IMGUI_API void          ShowMetricsWindow(bool* p_open = NULL);     // metrics window for debugging ImGui (browse draw commands, individual vertices, window list, etc.)
    122 
    123     // Window
    124     IMGUI_API bool          Begin(const char* name, bool* p_open = NULL, ImGuiWindowFlags flags = 0);                                                   // push window to the stack and start appending to it. see .cpp for details. return false when window is collapsed, so you can early out in your code. 'bool* p_open' creates a widget on the upper-right to close the window (which sets your bool to false).
    125     IMGUI_API bool          Begin(const char* name, bool* p_open, const ImVec2& size_on_first_use, float bg_alpha = -1.0f, ImGuiWindowFlags flags = 0); // OBSOLETE. this is the older/longer API. the extra parameters aren't very relevant. call SetNextWindowSize() instead if you want to set a window size. For regular windows, 'size_on_first_use' only applies to the first time EVER the window is created and probably not what you want! might obsolete this API eventually.
    126     IMGUI_API void          End();                                                                                                                      // finish appending to current window, pop it off the window stack.
    127     IMGUI_API bool          BeginChild(const char* str_id, const ImVec2& size = ImVec2(0,0), bool border = false, ImGuiWindowFlags extra_flags = 0);    // begin a scrolling region. size==0.0f: use remaining window size, size<0.0f: use remaining window size minus abs(size). size>0.0f: fixed size. each axis can use a different mode, e.g. ImVec2(0,400).
    128     IMGUI_API bool          BeginChild(ImGuiID id, const ImVec2& size = ImVec2(0,0), bool border = false, ImGuiWindowFlags extra_flags = 0);            // "
    129     IMGUI_API void          EndChild();
    130     IMGUI_API ImVec2        GetContentRegionMax();                                              // current content boundaries (typically window boundaries including scrolling, or current column boundaries), in windows coordinates
    131     IMGUI_API ImVec2        GetContentRegionAvail();                                            // == GetContentRegionMax() - GetCursorPos()
    132     IMGUI_API float         GetContentRegionAvailWidth();                                       //
    133     IMGUI_API ImVec2        GetWindowContentRegionMin();                                        // content boundaries min (roughly (0,0)-Scroll), in window coordinates
    134     IMGUI_API ImVec2        GetWindowContentRegionMax();                                        // content boundaries max (roughly (0,0)+Size-Scroll) where Size can be override with SetNextWindowContentSize(), in window coordinates
    135     IMGUI_API float         GetWindowContentRegionWidth();                                      //
    136     IMGUI_API ImDrawList*   GetWindowDrawList();                                                // get rendering command-list if you want to append your own draw primitives
    137     IMGUI_API ImVec2        GetWindowPos();                                                     // get current window position in screen space (useful if you want to do your own drawing via the DrawList api)
    138     IMGUI_API ImVec2        GetWindowSize();                                                    // get current window size
    139     IMGUI_API float         GetWindowWidth();
    140     IMGUI_API float         GetWindowHeight();
    141     IMGUI_API bool          IsWindowCollapsed();
    142     IMGUI_API void          SetWindowFontScale(float scale);                                    // per-window font scale. Adjust IO.FontGlobalScale if you want to scale all windows
    143 
    144     IMGUI_API void          SetNextWindowPos(const ImVec2& pos, ImGuiSetCond cond = 0);         // set next window position. call before Begin()
    145     IMGUI_API void          SetNextWindowPosCenter(ImGuiSetCond cond = 0);                      // set next window position to be centered on screen. call before Begin()
    146     IMGUI_API void          SetNextWindowSize(const ImVec2& size, ImGuiSetCond cond = 0);       // set next window size. set axis to 0.0f to force an auto-fit on this axis. call before Begin()
    147     IMGUI_API void          SetNextWindowSizeConstraints(const ImVec2& size_min, const ImVec2& size_max, ImGuiSizeConstraintCallback custom_callback = NULL, void* custom_callback_data = NULL); // set next window size limits. use -1,-1 on either X/Y axis to preserve the current size. Use callback to apply non-trivial programmatic constraints.
    148     IMGUI_API void          SetNextWindowContentSize(const ImVec2& size);                       // set next window content size (enforce the range of scrollbars). set axis to 0.0f to leave it automatic. call before Begin()
    149     IMGUI_API void          SetNextWindowContentWidth(float width);                             // set next window content width (enforce the range of horizontal scrollbar). call before Begin()
    150     IMGUI_API void          SetNextWindowCollapsed(bool collapsed, ImGuiSetCond cond = 0);      // set next window collapsed state. call before Begin()
    151     IMGUI_API void          SetNextWindowFocus();                                               // set next window to be focused / front-most. call before Begin()
    152     IMGUI_API void          SetWindowPos(const ImVec2& pos, ImGuiSetCond cond = 0);             // (not recommended) set current window position - call within Begin()/End(). prefer using SetNextWindowPos(), as this may incur tearing and side-effects.
    153     IMGUI_API void          SetWindowSize(const ImVec2& size, ImGuiSetCond cond = 0);           // (not recommended) set current window size - call within Begin()/End(). set to ImVec2(0,0) to force an auto-fit. prefer using SetNextWindowSize(), as this may incur tearing and minor side-effects.    
    154     IMGUI_API void          SetWindowCollapsed(bool collapsed, ImGuiSetCond cond = 0);          // (not recommended) set current window collapsed state. prefer using SetNextWindowCollapsed().
    155     IMGUI_API void          SetWindowFocus();                                                   // (not recommended) set current window to be focused / front-most. prefer using SetNextWindowFocus().
    156     IMGUI_API void          SetWindowPos(const char* name, const ImVec2& pos, ImGuiSetCond cond = 0);      // set named window position.
    157     IMGUI_API void          SetWindowSize(const char* name, const ImVec2& size, ImGuiSetCond cond = 0);    // set named window size. set axis to 0.0f to force an auto-fit on this axis.
    158     IMGUI_API void          SetWindowCollapsed(const char* name, bool collapsed, ImGuiSetCond cond = 0);   // set named window collapsed state
    159     IMGUI_API void          SetWindowFocus(const char* name);                                              // set named window to be focused / front-most. use NULL to remove focus.
    160 
    161     IMGUI_API float         GetScrollX();                                                       // get scrolling amount [0..GetScrollMaxX()]
    162     IMGUI_API float         GetScrollY();                                                       // get scrolling amount [0..GetScrollMaxY()]
    163     IMGUI_API float         GetScrollMaxX();                                                    // get maximum scrolling amount ~~ ContentSize.X - WindowSize.X
    164     IMGUI_API float         GetScrollMaxY();                                                    // get maximum scrolling amount ~~ ContentSize.Y - WindowSize.Y
    165     IMGUI_API void          SetScrollX(float scroll_x);                                         // set scrolling amount [0..GetScrollMaxX()]
    166     IMGUI_API void          SetScrollY(float scroll_y);                                         // set scrolling amount [0..GetScrollMaxY()]
    167     IMGUI_API void          SetScrollHere(float center_y_ratio = 0.5f);                         // adjust scrolling amount to make current cursor position visible. center_y_ratio=0.0: top, 0.5: center, 1.0: bottom.
    168     IMGUI_API void          SetScrollFromPosY(float pos_y, float center_y_ratio = 0.5f);        // adjust scrolling amount to make given position valid. use GetCursorPos() or GetCursorStartPos()+offset to get valid positions.
    169     IMGUI_API void          SetKeyboardFocusHere(int offset = 0);                               // focus keyboard on the next widget. Use positive 'offset' to access sub components of a multiple component widget. Use negative 'offset' to access previous widgets.
    170     IMGUI_API void          SetStateStorage(ImGuiStorage* tree);                                // replace tree state storage with our own (if you want to manipulate it yourself, typically clear subsection of it)
    171     IMGUI_API ImGuiStorage* GetStateStorage();
    172 
    173     // Parameters stacks (shared)
    174     IMGUI_API void          PushFont(ImFont* font);                                             // use NULL as a shortcut to push default font
    175     IMGUI_API void          PopFont();
    176     IMGUI_API void          PushStyleColor(ImGuiCol idx, const ImVec4& col);
    177     IMGUI_API void          PopStyleColor(int count = 1);
    178     IMGUI_API void          PushStyleVar(ImGuiStyleVar idx, float val);
    179     IMGUI_API void          PushStyleVar(ImGuiStyleVar idx, const ImVec2& val);
    180     IMGUI_API void          PopStyleVar(int count = 1);
    181     IMGUI_API ImFont*       GetFont();                                                          // get current font
    182     IMGUI_API float         GetFontSize();                                                      // get current font size (= height in pixels) of current font with current scale applied
    183     IMGUI_API ImVec2        GetFontTexUvWhitePixel();                                           // get UV coordinate for a while pixel, useful to draw custom shapes via the ImDrawList API
    184     IMGUI_API ImU32         GetColorU32(ImGuiCol idx, float alpha_mul = 1.0f);                  // retrieve given style color with style alpha applied and optional extra alpha multiplier
    185     IMGUI_API ImU32         GetColorU32(const ImVec4& col);                                     // retrieve given color with style alpha applied
    186 
    187     // Parameters stacks (current window)
    188     IMGUI_API void          PushItemWidth(float item_width);                                    // width of items for the common item+label case, pixels. 0.0f = default to ~2/3 of windows width, >0.0f: width in pixels, <0.0f align xx pixels to the right of window (so -1.0f always align width to the right side)
    189     IMGUI_API void          PopItemWidth();
    190     IMGUI_API float         CalcItemWidth();                                                    // width of item given pushed settings and current cursor position
    191     IMGUI_API void          PushTextWrapPos(float wrap_pos_x = 0.0f);                           // word-wrapping for Text*() commands. < 0.0f: no wrapping; 0.0f: wrap to end of window (or column); > 0.0f: wrap at 'wrap_pos_x' position in window local space
    192     IMGUI_API void          PopTextWrapPos();
    193     IMGUI_API void          PushAllowKeyboardFocus(bool v);                                     // allow focusing using TAB/Shift-TAB, enabled by default but you can disable it for certain widgets
    194     IMGUI_API void          PopAllowKeyboardFocus();
    195     IMGUI_API void          PushButtonRepeat(bool repeat);                                      // in 'repeat' mode, Button*() functions return repeated true in a typematic manner (uses io.KeyRepeatDelay/io.KeyRepeatRate for now). Note that you can call IsItemActive() after any Button() to tell if the button is held in the current frame.
    196     IMGUI_API void          PopButtonRepeat();
    197 
    198     // Cursor / Layout
    199     IMGUI_API void          Separator();                                                        // horizontal line
    200     IMGUI_API void          SameLine(float pos_x = 0.0f, float spacing_w = -1.0f);              // call between widgets or groups to layout them horizontally
    201     IMGUI_API void          NewLine();                                                          // undo a SameLine()
    202     IMGUI_API void          Spacing();                                                          // add vertical spacing
    203     IMGUI_API void          Dummy(const ImVec2& size);                                          // add a dummy item of given size
    204     IMGUI_API void          Indent(float indent_w = 0.0f);                                      // move content position toward the right, by style.IndentSpacing or indent_w if >0
    205     IMGUI_API void          Unindent(float indent_w = 0.0f);                                    // move content position back to the left, by style.IndentSpacing or indent_w if >0
    206     IMGUI_API void          BeginGroup();                                                       // lock horizontal starting position + capture group bounding box into one "item" (so you can use IsItemHovered() or layout primitives such as SameLine() on whole group, etc.)
    207     IMGUI_API void          EndGroup();
    208     IMGUI_API ImVec2        GetCursorPos();                                                     // cursor position is relative to window position
    209     IMGUI_API float         GetCursorPosX();                                                    // "
    210     IMGUI_API float         GetCursorPosY();                                                    // "
    211     IMGUI_API void          SetCursorPos(const ImVec2& local_pos);                              // "
    212     IMGUI_API void          SetCursorPosX(float x);                                             // "
    213     IMGUI_API void          SetCursorPosY(float y);                                             // "
    214     IMGUI_API ImVec2        GetCursorStartPos();                                                // initial cursor position
    215     IMGUI_API ImVec2        GetCursorScreenPos();                                               // cursor position in absolute screen coordinates [0..io.DisplaySize] (useful to work with ImDrawList API)
    216     IMGUI_API void          SetCursorScreenPos(const ImVec2& pos);                              // cursor position in absolute screen coordinates [0..io.DisplaySize]
    217     IMGUI_API void          AlignFirstTextHeightToWidgets();                                    // call once if the first item on the line is a Text() item and you want to vertically lower it to match subsequent (bigger) widgets
    218     IMGUI_API float         GetTextLineHeight();                                                // height of font == GetWindowFontSize()
    219     IMGUI_API float         GetTextLineHeightWithSpacing();                                     // distance (in pixels) between 2 consecutive lines of text == GetWindowFontSize() + GetStyle().ItemSpacing.y
    220     IMGUI_API float         GetItemsLineHeightWithSpacing();                                    // distance (in pixels) between 2 consecutive lines of standard height widgets == GetWindowFontSize() + GetStyle().FramePadding.y*2 + GetStyle().ItemSpacing.y
    221 
    222     // Columns
    223     // You can also use SameLine(pos_x) for simplified columning. The columns API is still work-in-progress and rather lacking.
    224     IMGUI_API void          Columns(int count = 1, const char* id = NULL, bool border = true);  // setup number of columns. use an identifier to distinguish multiple column sets. close with Columns(1).
    225     IMGUI_API void          NextColumn();                                                       // next column
    226     IMGUI_API int           GetColumnIndex();                                                   // get current column index
    227     IMGUI_API float         GetColumnOffset(int column_index = -1);                             // get position of column line (in pixels, from the left side of the contents region). pass -1 to use current column, otherwise 0..GetcolumnsCount() inclusive. column 0 is usually 0.0f and not resizable unless you call this
    228     IMGUI_API void          SetColumnOffset(int column_index, float offset_x);                  // set position of column line (in pixels, from the left side of the contents region). pass -1 to use current column
    229     IMGUI_API float         GetColumnWidth(int column_index = -1);                              // column width (== GetColumnOffset(GetColumnIndex()+1) - GetColumnOffset(GetColumnOffset())
    230     IMGUI_API int           GetColumnsCount();                                                  // number of columns (what was passed to Columns())
    231 
    232     // ID scopes
    233     // If you are creating widgets in a loop you most likely want to push a unique identifier so ImGui can differentiate them.
    234     // You can also use the "##foobar" syntax within widget label to distinguish them from each others. Read "A primer on the use of labels/IDs" in the FAQ for more details.
    235     IMGUI_API void          PushID(const char* str_id);                                         // push identifier into the ID stack. IDs are hash of the *entire* stack!
    236     IMGUI_API void          PushID(const char* str_id_begin, const char* str_id_end);
    237     IMGUI_API void          PushID(const void* ptr_id);
    238     IMGUI_API void          PushID(int int_id);
    239     IMGUI_API void          PopID();
    240     IMGUI_API ImGuiID       GetID(const char* str_id);                                          // calculate unique ID (hash of whole ID stack + given parameter). useful if you want to query into ImGuiStorage yourself. otherwise rarely needed
    241     IMGUI_API ImGuiID       GetID(const char* str_id_begin, const char* str_id_end);
    242     IMGUI_API ImGuiID       GetID(const void* ptr_id);
    243 
    244     // Widgets
    245     IMGUI_API void          Text(const char* fmt, ...) IM_PRINTFARGS(1);
    246     IMGUI_API void          TextV(const char* fmt, va_list args);
    247     IMGUI_API void          TextColored(const ImVec4& col, const char* fmt, ...) IM_PRINTFARGS(2);  // shortcut for PushStyleColor(ImGuiCol_Text, col); Text(fmt, ...); PopStyleColor();
    248     IMGUI_API void          TextColoredV(const ImVec4& col, const char* fmt, va_list args);
    249     IMGUI_API void          TextDisabled(const char* fmt, ...) IM_PRINTFARGS(1);                    // shortcut for PushStyleColor(ImGuiCol_Text, style.Colors[ImGuiCol_TextDisabled]); Text(fmt, ...); PopStyleColor();
    250     IMGUI_API void          TextDisabledV(const char* fmt, va_list args);
    251     IMGUI_API void          TextWrapped(const char* fmt, ...) IM_PRINTFARGS(1);                     // shortcut for PushTextWrapPos(0.0f); Text(fmt, ...); PopTextWrapPos();. Note that this won't work on an auto-resizing window if there's no other widgets to extend the window width, yoy may need to set a size using SetNextWindowSize().
    252     IMGUI_API void          TextWrappedV(const char* fmt, va_list args);
    253     IMGUI_API void          TextUnformatted(const char* text, const char* text_end = NULL);         // doesn't require null terminated string if 'text_end' is specified. no copy done to any bounded stack buffer, recommended for long chunks of text
    254     IMGUI_API void          LabelText(const char* label, const char* fmt, ...) IM_PRINTFARGS(2);    // display text+label aligned the same way as value+label widgets
    255     IMGUI_API void          LabelTextV(const char* label, const char* fmt, va_list args);
    256     IMGUI_API void          Bullet();                                                               // draw a small circle and keep the cursor on the same line. advance cursor x position by GetTreeNodeToLabelSpacing(), same distance that TreeNode() uses
    257     IMGUI_API void          BulletText(const char* fmt, ...) IM_PRINTFARGS(1);                      // shortcut for Bullet()+Text()
    258     IMGUI_API void          BulletTextV(const char* fmt, va_list args);
    259     IMGUI_API bool          Button(const char* label, const ImVec2& size = ImVec2(0,0));            // button
    260     IMGUI_API bool          SmallButton(const char* label);                                         // button with FramePadding=(0,0)
    261     IMGUI_API bool          InvisibleButton(const char* str_id, const ImVec2& size);
    262     IMGUI_API void          Image(ImTextureID user_texture_id, const ImVec2& size, const ImVec2& uv0 = ImVec2(0,0), const ImVec2& uv1 = ImVec2(1,1), const ImVec4& tint_col = ImVec4(1,1,1,1), const ImVec4& border_col = ImVec4(0,0,0,0));
    263     IMGUI_API bool          ImageButton(ImTextureID user_texture_id, const ImVec2& size, const ImVec2& uv0 = ImVec2(0,0),  const ImVec2& uv1 = ImVec2(1,1), int frame_padding = -1, const ImVec4& bg_col = ImVec4(0,0,0,0), const ImVec4& tint_col = ImVec4(1,1,1,1));    // <0 frame_padding uses default frame padding settings. 0 for no padding
    264     IMGUI_API bool          Checkbox(const char* label, bool* v);
    265     IMGUI_API bool          CheckboxFlags(const char* label, unsigned int* flags, unsigned int flags_value);
    266     IMGUI_API bool          RadioButton(const char* label, bool active);
    267     IMGUI_API bool          RadioButton(const char* label, int* v, int v_button);
    268     IMGUI_API bool          Combo(const char* label, int* current_item, const char* const* items, int items_count, int height_in_items = -1);
    269     IMGUI_API bool          Combo(const char* label, int* current_item, const char* items_separated_by_zeros, int height_in_items = -1);      // separate items with \0, end item-list with \0\0
    270     IMGUI_API bool          Combo(const char* label, int* current_item, bool (*items_getter)(void* data, int idx, const char** out_text), void* data, int items_count, int height_in_items = -1);
    271     IMGUI_API bool          ColorButton(const ImVec4& col, bool small_height = false, bool outline_border = true);
    272     IMGUI_API bool          ColorEdit3(const char* label, float col[3]);                            // Hint: 'float col[3]' function argument is same as 'float* col'. You can pass address of first element out of a contiguous set, e.g. &myvector.x
    273     IMGUI_API bool          ColorEdit4(const char* label, float col[4], bool show_alpha = true);    // "
    274     IMGUI_API void          ColorEditMode(ImGuiColorEditMode mode);                                 // FIXME-OBSOLETE: This is inconsistent with most of the API and will be obsoleted/replaced.
    275     IMGUI_API void          PlotLines(const char* label, const float* values, int values_count, int values_offset = 0, const char* overlay_text = NULL, float scale_min = FLT_MAX, float scale_max = FLT_MAX, ImVec2 graph_size = ImVec2(0,0), int stride = sizeof(float));
    276     IMGUI_API void          PlotLines(const char* label, float (*values_getter)(void* data, int idx), void* data, int values_count, int values_offset = 0, const char* overlay_text = NULL, float scale_min = FLT_MAX, float scale_max = FLT_MAX, ImVec2 graph_size = ImVec2(0,0));
    277     IMGUI_API void          PlotHistogram(const char* label, const float* values, int values_count, int values_offset = 0, const char* overlay_text = NULL, float scale_min = FLT_MAX, float scale_max = FLT_MAX, ImVec2 graph_size = ImVec2(0,0), int stride = sizeof(float));
    278     IMGUI_API void          PlotHistogram(const char* label, float (*values_getter)(void* data, int idx), void* data, int values_count, int values_offset = 0, const char* overlay_text = NULL, float scale_min = FLT_MAX, float scale_max = FLT_MAX, ImVec2 graph_size = ImVec2(0,0));
    279     IMGUI_API void          ProgressBar(float fraction, const ImVec2& size_arg = ImVec2(-1,0), const char* overlay = NULL);
    280 
    281     // Widgets: Drags (tip: ctrl+click on a drag box to input with keyboard. manually input values aren't clamped, can go off-bounds)
    282     // For all the Float2/Float3/Float4/Int2/Int3/Int4 versions of every functions, remember than a 'float v[3]' function argument is the same as 'float* v'. You can pass address of your first element out of a contiguous set, e.g. &myvector.x
    283     IMGUI_API bool          DragFloat(const char* label, float* v, float v_speed = 1.0f, float v_min = 0.0f, float v_max = 0.0f, const char* display_format = "%.3f", float power = 1.0f);     // If v_min >= v_max we have no bound
    284     IMGUI_API bool          DragFloat2(const char* label, float v[2], float v_speed = 1.0f, float v_min = 0.0f, float v_max = 0.0f, const char* display_format = "%.3f", float power = 1.0f);
    285     IMGUI_API bool          DragFloat3(const char* label, float v[3], float v_speed = 1.0f, float v_min = 0.0f, float v_max = 0.0f, const char* display_format = "%.3f", float power = 1.0f);
    286     IMGUI_API bool          DragFloat4(const char* label, float v[4], float v_speed = 1.0f, float v_min = 0.0f, float v_max = 0.0f, const char* display_format = "%.3f", float power = 1.0f);
    287     IMGUI_API bool          DragFloatRange2(const char* label, float* v_current_min, float* v_current_max, float v_speed = 1.0f, float v_min = 0.0f, float v_max = 0.0f, const char* display_format = "%.3f", const char* display_format_max = NULL, float power = 1.0f);
    288     IMGUI_API bool          DragInt(const char* label, int* v, float v_speed = 1.0f, int v_min = 0, int v_max = 0, const char* display_format = "%.0f");                                       // If v_min >= v_max we have no bound
    289     IMGUI_API bool          DragInt2(const char* label, int v[2], float v_speed = 1.0f, int v_min = 0, int v_max = 0, const char* display_format = "%.0f");
    290     IMGUI_API bool          DragInt3(const char* label, int v[3], float v_speed = 1.0f, int v_min = 0, int v_max = 0, const char* display_format = "%.0f");
    291     IMGUI_API bool          DragInt4(const char* label, int v[4], float v_speed = 1.0f, int v_min = 0, int v_max = 0, const char* display_format = "%.0f");
    292     IMGUI_API bool          DragIntRange2(const char* label, int* v_current_min, int* v_current_max, float v_speed = 1.0f, int v_min = 0, int v_max = 0, const char* display_format = "%.0f", const char* display_format_max = NULL);
    293 
    294     // Widgets: Input with Keyboard
    295     IMGUI_API bool          InputText(const char* label, char* buf, size_t buf_size, ImGuiInputTextFlags flags = 0, ImGuiTextEditCallback callback = NULL, void* user_data = NULL);
    296     IMGUI_API bool          InputTextMultiline(const char* label, char* buf, size_t buf_size, const ImVec2& size = ImVec2(0,0), ImGuiInputTextFlags flags = 0, ImGuiTextEditCallback callback = NULL, void* user_data = NULL);
    297     IMGUI_API bool          InputFloat(const char* label, float* v, float step = 0.0f, float step_fast = 0.0f, int decimal_precision = -1, ImGuiInputTextFlags extra_flags = 0);
    298     IMGUI_API bool          InputFloat2(const char* label, float v[2], int decimal_precision = -1, ImGuiInputTextFlags extra_flags = 0);
    299     IMGUI_API bool          InputFloat3(const char* label, float v[3], int decimal_precision = -1, ImGuiInputTextFlags extra_flags = 0);
    300     IMGUI_API bool          InputFloat4(const char* label, float v[4], int decimal_precision = -1, ImGuiInputTextFlags extra_flags = 0);
    301     IMGUI_API bool          InputInt(const char* label, int* v, int step = 1, int step_fast = 100, ImGuiInputTextFlags extra_flags = 0);
    302     IMGUI_API bool          InputInt2(const char* label, int v[2], ImGuiInputTextFlags extra_flags = 0);
    303     IMGUI_API bool          InputInt3(const char* label, int v[3], ImGuiInputTextFlags extra_flags = 0);
    304     IMGUI_API bool          InputInt4(const char* label, int v[4], ImGuiInputTextFlags extra_flags = 0);
    305 
    306     // Widgets: Sliders (tip: ctrl+click on a slider to input with keyboard. manually input values aren't clamped, can go off-bounds)
    307     IMGUI_API bool          SliderFloat(const char* label, float* v, float v_min, float v_max, const char* display_format = "%.3f", float power = 1.0f);     // adjust display_format to decorate the value with a prefix or a suffix. Use power!=1.0 for logarithmic sliders
    308     IMGUI_API bool          SliderFloat2(const char* label, float v[2], float v_min, float v_max, const char* display_format = "%.3f", float power = 1.0f);
    309     IMGUI_API bool          SliderFloat3(const char* label, float v[3], float v_min, float v_max, const char* display_format = "%.3f", float power = 1.0f);
    310     IMGUI_API bool          SliderFloat4(const char* label, float v[4], float v_min, float v_max, const char* display_format = "%.3f", float power = 1.0f);
    311     IMGUI_API bool          SliderAngle(const char* label, float* v_rad, float v_degrees_min = -360.0f, float v_degrees_max = +360.0f);
    312     IMGUI_API bool          SliderInt(const char* label, int* v, int v_min, int v_max, const char* display_format = "%.0f");
    313     IMGUI_API bool          SliderInt2(const char* label, int v[2], int v_min, int v_max, const char* display_format = "%.0f");
    314     IMGUI_API bool          SliderInt3(const char* label, int v[3], int v_min, int v_max, const char* display_format = "%.0f");
    315     IMGUI_API bool          SliderInt4(const char* label, int v[4], int v_min, int v_max, const char* display_format = "%.0f");
    316     IMGUI_API bool          VSliderFloat(const char* label, const ImVec2& size, float* v, float v_min, float v_max, const char* display_format = "%.3f", float power = 1.0f);
    317     IMGUI_API bool          VSliderInt(const char* label, const ImVec2& size, int* v, int v_min, int v_max, const char* display_format = "%.0f");
    318 
    319     // Widgets: Trees
    320     IMGUI_API bool          TreeNode(const char* label);                                            // if returning 'true' the node is open and the tree id is pushed into the id stack. user is responsible for calling TreePop().
    321     IMGUI_API bool          TreeNode(const char* str_id, const char* fmt, ...) IM_PRINTFARGS(2);    // read the FAQ about why and how to use ID. to align arbitrary text at the same level as a TreeNode() you can use Bullet().
    322     IMGUI_API bool          TreeNode(const void* ptr_id, const char* fmt, ...) IM_PRINTFARGS(2);    // "
    323     IMGUI_API bool          TreeNodeV(const char* str_id, const char* fmt, va_list args);           // "
    324     IMGUI_API bool          TreeNodeV(const void* ptr_id, const char* fmt, va_list args);           // "
    325     IMGUI_API bool          TreeNodeEx(const char* label, ImGuiTreeNodeFlags flags = 0);
    326     IMGUI_API bool          TreeNodeEx(const char* str_id, ImGuiTreeNodeFlags flags, const char* fmt, ...) IM_PRINTFARGS(3);
    327     IMGUI_API bool          TreeNodeEx(const void* ptr_id, ImGuiTreeNodeFlags flags, const char* fmt, ...) IM_PRINTFARGS(3);
    328     IMGUI_API bool          TreeNodeExV(const char* str_id, ImGuiTreeNodeFlags flags, const char* fmt, va_list args);
    329     IMGUI_API bool          TreeNodeExV(const void* ptr_id, ImGuiTreeNodeFlags flags, const char* fmt, va_list args);
    330     IMGUI_API void          TreePush(const char* str_id = NULL);                                    // ~ Indent()+PushId(). Already called by TreeNode() when returning true, but you can call Push/Pop yourself for layout purpose
    331     IMGUI_API void          TreePush(const void* ptr_id = NULL);                                    // "
    332     IMGUI_API void          TreePop();                                                              // ~ Unindent()+PopId()
    333     IMGUI_API void          TreeAdvanceToLabelPos();                                                // advance cursor x position by GetTreeNodeToLabelSpacing()
    334     IMGUI_API float         GetTreeNodeToLabelSpacing();                                            // horizontal distance preceding label when using TreeNode*() or Bullet() == (g.FontSize + style.FramePadding.x*2) for a regular unframed TreeNode
    335     IMGUI_API void          SetNextTreeNodeOpen(bool is_open, ImGuiSetCond cond = 0);               // set next TreeNode/CollapsingHeader open state.
    336     IMGUI_API bool          CollapsingHeader(const char* label, ImGuiTreeNodeFlags flags = 0);      // if returning 'true' the header is open. doesn't indent nor push on ID stack. user doesn't have to call TreePop().
    337     IMGUI_API bool          CollapsingHeader(const char* label, bool* p_open, ImGuiTreeNodeFlags flags = 0); // when 'p_open' isn't NULL, display an additional small close button on upper right of the header
    338 
    339     // Widgets: Selectable / Lists
    340     IMGUI_API bool          Selectable(const char* label, bool selected = false, ImGuiSelectableFlags flags = 0, const ImVec2& size = ImVec2(0,0));  // size.x==0.0: use remaining width, size.x>0.0: specify width. size.y==0.0: use label height, size.y>0.0: specify height
    341     IMGUI_API bool          Selectable(const char* label, bool* p_selected, ImGuiSelectableFlags flags = 0, const ImVec2& size = ImVec2(0,0));
    342     IMGUI_API bool          ListBox(const char* label, int* current_item, const char* const* items, int items_count, int height_in_items = -1);
    343     IMGUI_API bool          ListBox(const char* label, int* current_item, bool (*items_getter)(void* data, int idx, const char** out_text), void* data, int items_count, int height_in_items = -1);
    344     IMGUI_API bool          ListBoxHeader(const char* label, const ImVec2& size = ImVec2(0,0)); // use if you want to reimplement ListBox() will custom data or interactions. make sure to call ListBoxFooter() afterwards.
    345     IMGUI_API bool          ListBoxHeader(const char* label, int items_count, int height_in_items = -1); // "
    346     IMGUI_API void          ListBoxFooter();                                                    // terminate the scrolling region
    347 
    348     // Widgets: Value() Helpers. Output single value in "name: value" format (tip: freely declare more in your code to handle your types. you can add functions to the ImGui namespace)
    349     IMGUI_API void          Value(const char* prefix, bool b);
    350     IMGUI_API void          Value(const char* prefix, int v);
    351     IMGUI_API void          Value(const char* prefix, unsigned int v);
    352     IMGUI_API void          Value(const char* prefix, float v, const char* float_format = NULL);
    353     IMGUI_API void          ValueColor(const char* prefix, const ImVec4& v);
    354     IMGUI_API void          ValueColor(const char* prefix, ImU32 v);
    355 
    356     // Tooltips
    357     IMGUI_API void          SetTooltip(const char* fmt, ...) IM_PRINTFARGS(1);                  // set tooltip under mouse-cursor, typically use with ImGui::IsHovered(). last call wins
    358     IMGUI_API void          SetTooltipV(const char* fmt, va_list args);
    359     IMGUI_API void          BeginTooltip();                                                     // use to create full-featured tooltip windows that aren't just text
    360     IMGUI_API void          EndTooltip();
    361 
    362     // Menus
    363     IMGUI_API bool          BeginMainMenuBar();                                                 // create and append to a full screen menu-bar. only call EndMainMenuBar() if this returns true!
    364     IMGUI_API void          EndMainMenuBar();
    365     IMGUI_API bool          BeginMenuBar();                                                     // append to menu-bar of current window (requires ImGuiWindowFlags_MenuBar flag set). only call EndMenuBar() if this returns true!
    366     IMGUI_API void          EndMenuBar();
    367     IMGUI_API bool          BeginMenu(const char* label, bool enabled = true);                  // create a sub-menu entry. only call EndMenu() if this returns true!
    368     IMGUI_API void          EndMenu();
    369     IMGUI_API bool          MenuItem(const char* label, const char* shortcut = NULL, bool selected = false, bool enabled = true);  // return true when activated. shortcuts are displayed for convenience but not processed by ImGui at the moment
    370     IMGUI_API bool          MenuItem(const char* label, const char* shortcut, bool* p_selected, bool enabled = true);              // return true when activated + toggle (*p_selected) if p_selected != NULL
    371 
    372     // Popups
    373     IMGUI_API void          OpenPopup(const char* str_id);                                      // mark popup as open. popups are closed when user click outside, or activate a pressable item, or CloseCurrentPopup() is called within a BeginPopup()/EndPopup() block. popup identifiers are relative to the current ID-stack (so OpenPopup and BeginPopup needs to be at the same level).
    374     IMGUI_API bool          BeginPopup(const char* str_id);                                     // return true if the popup is open, and you can start outputting to it. only call EndPopup() if BeginPopup() returned true!
    375     IMGUI_API bool          BeginPopupModal(const char* name, bool* p_open = NULL, ImGuiWindowFlags extra_flags = 0);               // modal dialog (block interactions behind the modal window, can't close the modal window by clicking outside)
    376     IMGUI_API bool          BeginPopupContextItem(const char* str_id, int mouse_button = 1);                                        // helper to open and begin popup when clicked on last item. read comments in .cpp!
    377     IMGUI_API bool          BeginPopupContextWindow(bool also_over_items = true, const char* str_id = NULL, int mouse_button = 1);  // helper to open and begin popup when clicked on current window.
    378     IMGUI_API bool          BeginPopupContextVoid(const char* str_id = NULL, int mouse_button = 1);                                 // helper to open and begin popup when clicked in void (no window).
    379     IMGUI_API void          EndPopup();
    380     IMGUI_API void          CloseCurrentPopup();                                                // close the popup we have begin-ed into. clicking on a MenuItem or Selectable automatically close the current popup.
    381 
    382     // Logging: all text output from interface is redirected to tty/file/clipboard. By default, tree nodes are automatically opened during logging.
    383     IMGUI_API void          LogToTTY(int max_depth = -1);                                       // start logging to tty
    384     IMGUI_API void          LogToFile(int max_depth = -1, const char* filename = NULL);         // start logging to file
    385     IMGUI_API void          LogToClipboard(int max_depth = -1);                                 // start logging to OS clipboard
    386     IMGUI_API void          LogFinish();                                                        // stop logging (close file, etc.)
    387     IMGUI_API void          LogButtons();                                                       // helper to display buttons for logging to tty/file/clipboard
    388     IMGUI_API void          LogText(const char* fmt, ...) IM_PRINTFARGS(1);                     // pass text data straight to log (without being displayed)
    389 
    390     // Clipping
    391     IMGUI_API void          PushClipRect(const ImVec2& clip_rect_min, const ImVec2& clip_rect_max, bool intersect_with_current_clip_rect);
    392     IMGUI_API void          PopClipRect();
    393 
    394     // Utilities
    395     IMGUI_API bool          IsItemHovered();                                                    // was the last item hovered by mouse?
    396     IMGUI_API bool          IsItemHoveredRect();                                                // was the last item hovered by mouse? even if another item is active or window is blocked by popup while we are hovering this
    397     IMGUI_API bool          IsItemActive();                                                     // was the last item active? (e.g. button being held, text field being edited- items that don't interact will always return false)
    398     IMGUI_API bool          IsItemClicked(int mouse_button = 0);                                // was the last item clicked? (e.g. button/node just clicked on)
    399     IMGUI_API bool          IsItemVisible();                                                    // was the last item visible? (aka not out of sight due to clipping/scrolling.)
    400     IMGUI_API bool          IsAnyItemHovered();
    401     IMGUI_API bool          IsAnyItemActive();
    402     IMGUI_API ImVec2        GetItemRectMin();                                                   // get bounding rect of last item in screen space
    403     IMGUI_API ImVec2        GetItemRectMax();                                                   // "
    404     IMGUI_API ImVec2        GetItemRectSize();                                                  // "
    405     IMGUI_API void          SetItemAllowOverlap();                                              // allow last item to be overlapped by a subsequent item. sometimes useful with invisible buttons, selectables, etc. to catch unused area.
    406     IMGUI_API bool          IsWindowHovered();                                                  // is current window hovered and hoverable (not blocked by a popup) (differentiate child windows from each others)
    407     IMGUI_API bool          IsWindowFocused();                                                  // is current window focused
    408     IMGUI_API bool          IsRootWindowFocused();                                              // is current root window focused (root = top-most parent of a child, otherwise self)
    409     IMGUI_API bool          IsRootWindowOrAnyChildFocused();                                    // is current root window or any of its child (including current window) focused
    410     IMGUI_API bool          IsRootWindowOrAnyChildHovered();                                    // is current root window or any of its child (including current window) hovered and hoverable (not blocked by a popup)
    411     IMGUI_API bool          IsRectVisible(const ImVec2& size);                                  // test if rectangle (of given size, starting from cursor position) is visible / not clipped.
    412     IMGUI_API bool          IsRectVisible(const ImVec2& rect_min, const ImVec2& rect_max);      // test if rectangle (in screen space) is visible / not clipped. to perform coarse clipping on user's side.
    413     IMGUI_API bool          IsPosHoveringAnyWindow(const ImVec2& pos);                          // is given position hovering any active imgui window
    414     IMGUI_API float         GetTime();
    415     IMGUI_API int           GetFrameCount();
    416     IMGUI_API const char*   GetStyleColName(ImGuiCol idx);
    417     IMGUI_API ImVec2        CalcItemRectClosestPoint(const ImVec2& pos, bool on_edge = false, float outward = +0.0f);   // utility to find the closest point the last item bounding rectangle edge. useful to visually link items
    418     IMGUI_API ImVec2        CalcTextSize(const char* text, const char* text_end = NULL, bool hide_text_after_double_hash = false, float wrap_width = -1.0f);
    419     IMGUI_API void          CalcListClipping(int items_count, float items_height, int* out_items_display_start, int* out_items_display_end);    // calculate coarse clipping for large list of evenly sized items. Prefer using the ImGuiListClipper higher-level helper if you can.
    420 
    421     IMGUI_API bool          BeginChildFrame(ImGuiID id, const ImVec2& size, ImGuiWindowFlags extra_flags = 0);	// helper to create a child window / scrolling region that looks like a normal widget frame
    422     IMGUI_API void          EndChildFrame();
    423 
    424     IMGUI_API ImVec4        ColorConvertU32ToFloat4(ImU32 in);
    425     IMGUI_API ImU32         ColorConvertFloat4ToU32(const ImVec4& in);
    426     IMGUI_API void          ColorConvertRGBtoHSV(float r, float g, float b, float& out_h, float& out_s, float& out_v);
    427     IMGUI_API void          ColorConvertHSVtoRGB(float h, float s, float v, float& out_r, float& out_g, float& out_b);
    428 
    429     // Inputs
    430     IMGUI_API int           GetKeyIndex(ImGuiKey imgui_key);                                    // map ImGuiKey_* values into user's key index. == io.KeyMap[key]
    431     IMGUI_API bool          IsKeyDown(int user_key_index);                                      // is key being held. == io.KeysDown[user_key_index]. note that imgui doesn't know the semantic of each entry of io.KeyDown[]. Use your own indices/enums according to how your backend/engine stored them into KeyDown[]!
    432     IMGUI_API bool          IsKeyPressed(int user_key_index, bool repeat = true);               // was key pressed (went from !Down to Down). if repeat=true, uses io.KeyRepeatDelay / KeyRepeatRate
    433     IMGUI_API bool          IsKeyReleased(int user_key_index);                                  // was key released (went from Down to !Down)..
    434     IMGUI_API bool          IsMouseDown(int button);                                            // is mouse button held
    435     IMGUI_API bool          IsMouseClicked(int button, bool repeat = false);                    // did mouse button clicked (went from !Down to Down)
    436     IMGUI_API bool          IsMouseDoubleClicked(int button);                                   // did mouse button double-clicked. a double-click returns false in IsMouseClicked(). uses io.MouseDoubleClickTime.
    437     IMGUI_API bool          IsMouseReleased(int button);                                        // did mouse button released (went from Down to !Down)
    438     IMGUI_API bool          IsMouseHoveringWindow();                                            // is mouse hovering current window ("window" in API names always refer to current window). disregarding of any consideration of being blocked by a popup. (unlike IsWindowHovered() this will return true even if the window is blocked because of a popup)
    439     IMGUI_API bool          IsMouseHoveringAnyWindow();                                         // is mouse hovering any visible window
    440     IMGUI_API bool          IsMouseHoveringRect(const ImVec2& r_min, const ImVec2& r_max, bool clip = true);  // is mouse hovering given bounding rect (in screen space). clipped by current clipping settings. disregarding of consideration of focus/window ordering/blocked by a popup.
    441     IMGUI_API bool          IsMouseDragging(int button = 0, float lock_threshold = -1.0f);      // is mouse dragging. if lock_threshold < -1.0f uses io.MouseDraggingThreshold
    442     IMGUI_API ImVec2        GetMousePos();                                                      // shortcut to ImGui::GetIO().MousePos provided by user, to be consistent with other calls
    443     IMGUI_API ImVec2        GetMousePosOnOpeningCurrentPopup();                                 // retrieve backup of mouse positioning at the time of opening popup we have BeginPopup() into
    444     IMGUI_API ImVec2        GetMouseDragDelta(int button = 0, float lock_threshold = -1.0f);    // dragging amount since clicking. if lock_threshold < -1.0f uses io.MouseDraggingThreshold
    445     IMGUI_API void          ResetMouseDragDelta(int button = 0);                                //
    446     IMGUI_API ImGuiMouseCursor GetMouseCursor();                                                // get desired cursor type, reset in ImGui::NewFrame(), this updated during the frame. valid before Render(). If you use software rendering by setting io.MouseDrawCursor ImGui will render those for you
    447     IMGUI_API void          SetMouseCursor(ImGuiMouseCursor type);                              // set desired cursor type
    448     IMGUI_API void          CaptureKeyboardFromApp(bool capture = true);                        // manually override io.WantCaptureKeyboard flag next frame (said flag is entirely left for your application handle). e.g. force capture keyboard when your widget is being hovered.
    449     IMGUI_API void          CaptureMouseFromApp(bool capture = true);                           // manually override io.WantCaptureMouse flag next frame (said flag is entirely left for your application handle).
    450 
    451     // Helpers functions to access functions pointers in ImGui::GetIO()
    452     IMGUI_API void*         MemAlloc(size_t sz);
    453     IMGUI_API void          MemFree(void* ptr);
    454     IMGUI_API const char*   GetClipboardText();
    455     IMGUI_API void          SetClipboardText(const char* text);
    456 
    457     // Internal context access - if you want to use multiple context, share context between modules (e.g. DLL). There is a default context created and active by default.
    458     // All contexts share a same ImFontAtlas by default. If you want different font atlas, you can new() them and overwrite the GetIO().Fonts variable of an ImGui context.
    459     IMGUI_API const char*   GetVersion();
    460     IMGUI_API ImGuiContext* CreateContext(void* (*malloc_fn)(size_t) = NULL, void (*free_fn)(void*) = NULL);
    461     IMGUI_API void          DestroyContext(ImGuiContext* ctx);
    462     IMGUI_API ImGuiContext* GetCurrentContext();
    463     IMGUI_API void          SetCurrentContext(ImGuiContext* ctx);
    464 
    465     // Obsolete (will be removed)
    466 #ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
    467     static inline bool      CollapsingHeader(const char* label, const char* str_id, bool framed = true, bool default_open = false) { (void)str_id; (void)framed; ImGuiTreeNodeFlags default_open_flags = 1<<5; return CollapsingHeader(label, (default_open ? default_open_flags : 0)); } // OBSOLETE 1.49+
    468     static inline ImFont*   GetWindowFont() { return GetFont(); }                              // OBSOLETE 1.48+
    469     static inline float     GetWindowFontSize() { return GetFontSize(); }                      // OBSOLETE 1.48+
    470     static inline void      SetScrollPosHere() { SetScrollHere(); }                            // OBSOLETE 1.42+
    471     static inline bool      GetWindowCollapsed() { return ImGui::IsWindowCollapsed(); }        // OBSOLETE 1.39+
    472     static inline bool      IsRectClipped(const ImVec2& size) { return !IsRectVisible(size); } // OBSOLETE 1.39+
    473 #endif
    474 
    475 } // namespace ImGui
    476 
    477 // Flags for ImGui::Begin()
    478 enum ImGuiWindowFlags_
    479 {
    480     // Default: 0
    481     ImGuiWindowFlags_NoTitleBar             = 1 << 0,   // Disable title-bar
    482     ImGuiWindowFlags_NoResize               = 1 << 1,   // Disable user resizing with the lower-right grip
    483     ImGuiWindowFlags_NoMove                 = 1 << 2,   // Disable user moving the window
    484     ImGuiWindowFlags_NoScrollbar            = 1 << 3,   // Disable scrollbars (window can still scroll with mouse or programatically)
    485     ImGuiWindowFlags_NoScrollWithMouse      = 1 << 4,   // Disable user vertically scrolling with mouse wheel
    486     ImGuiWindowFlags_NoCollapse             = 1 << 5,   // Disable user collapsing window by double-clicking on it
    487     ImGuiWindowFlags_AlwaysAutoResize       = 1 << 6,   // Resize every window to its content every frame
    488     ImGuiWindowFlags_ShowBorders            = 1 << 7,   // Show borders around windows and items
    489     ImGuiWindowFlags_NoSavedSettings        = 1 << 8,   // Never load/save settings in .ini file
    490     ImGuiWindowFlags_NoInputs               = 1 << 9,   // Disable catching mouse or keyboard inputs
    491     ImGuiWindowFlags_MenuBar                = 1 << 10,  // Has a menu-bar
    492     ImGuiWindowFlags_HorizontalScrollbar    = 1 << 11,  // Allow horizontal scrollbar to appear (off by default). You may use SetNextWindowContentSize(ImVec2(width,0.0f)); prior to calling Begin() to specify width. Read code in imgui_demo in the "Horizontal Scrolling" section.
    493     ImGuiWindowFlags_NoFocusOnAppearing     = 1 << 12,  // Disable taking focus when transitioning from hidden to visible state
    494     ImGuiWindowFlags_NoBringToFrontOnFocus  = 1 << 13,  // Disable bringing window to front when taking focus (e.g. clicking on it or programatically giving it focus)
    495     ImGuiWindowFlags_AlwaysVerticalScrollbar= 1 << 14,  // Always show vertical scrollbar (even if ContentSize.y < Size.y)
    496     ImGuiWindowFlags_AlwaysHorizontalScrollbar=1<< 15,  // Always show horizontal scrollbar (even if ContentSize.x < Size.x)
    497     ImGuiWindowFlags_AlwaysUseWindowPadding = 1 << 16,  // Ensure child windows without border uses style.WindowPadding (ignored by default for non-bordered child windows, because more convenient)
    498     // [Internal]
    499     ImGuiWindowFlags_ChildWindow            = 1 << 20,  // Don't use! For internal use by BeginChild()
    500     ImGuiWindowFlags_ChildWindowAutoFitX    = 1 << 21,  // Don't use! For internal use by BeginChild()
    501     ImGuiWindowFlags_ChildWindowAutoFitY    = 1 << 22,  // Don't use! For internal use by BeginChild()
    502     ImGuiWindowFlags_ComboBox               = 1 << 23,  // Don't use! For internal use by ComboBox()
    503     ImGuiWindowFlags_Tooltip                = 1 << 24,  // Don't use! For internal use by BeginTooltip()
    504     ImGuiWindowFlags_Popup                  = 1 << 25,  // Don't use! For internal use by BeginPopup()
    505     ImGuiWindowFlags_Modal                  = 1 << 26,  // Don't use! For internal use by BeginPopupModal()
    506     ImGuiWindowFlags_ChildMenu              = 1 << 27   // Don't use! For internal use by BeginMenu()
    507 };
    508 
    509 // Flags for ImGui::InputText()
    510 enum ImGuiInputTextFlags_
    511 {
    512     // Default: 0
    513     ImGuiInputTextFlags_CharsDecimal        = 1 << 0,   // Allow 0123456789.+-*/
    514     ImGuiInputTextFlags_CharsHexadecimal    = 1 << 1,   // Allow 0123456789ABCDEFabcdef
    515     ImGuiInputTextFlags_CharsUppercase      = 1 << 2,   // Turn a..z into A..Z
    516     ImGuiInputTextFlags_CharsNoBlank        = 1 << 3,   // Filter out spaces, tabs
    517     ImGuiInputTextFlags_AutoSelectAll       = 1 << 4,   // Select entire text when first taking mouse focus
    518     ImGuiInputTextFlags_EnterReturnsTrue    = 1 << 5,   // Return 'true' when Enter is pressed (as opposed to when the value was modified)
    519     ImGuiInputTextFlags_CallbackCompletion  = 1 << 6,   // Call user function on pressing TAB (for completion handling)
    520     ImGuiInputTextFlags_CallbackHistory     = 1 << 7,   // Call user function on pressing Up/Down arrows (for history handling)
    521     ImGuiInputTextFlags_CallbackAlways      = 1 << 8,   // Call user function every time. User code may query cursor position, modify text buffer.
    522     ImGuiInputTextFlags_CallbackCharFilter  = 1 << 9,   // Call user function to filter character. Modify data->EventChar to replace/filter input, or return 1 to discard character.
    523     ImGuiInputTextFlags_AllowTabInput       = 1 << 10,  // Pressing TAB input a '\t' character into the text field
    524     ImGuiInputTextFlags_CtrlEnterForNewLine = 1 << 11,  // In multi-line mode, unfocus with Enter, add new line with Ctrl+Enter (default is opposite: unfocus with Ctrl+Enter, add line with Enter).
    525     ImGuiInputTextFlags_NoHorizontalScroll  = 1 << 12,  // Disable following the cursor horizontally
    526     ImGuiInputTextFlags_AlwaysInsertMode    = 1 << 13,  // Insert mode
    527     ImGuiInputTextFlags_ReadOnly            = 1 << 14,  // Read-only mode
    528     ImGuiInputTextFlags_Password            = 1 << 15,  // Password mode, display all characters as '*'
    529     // [Internal]
    530     ImGuiInputTextFlags_Multiline           = 1 << 20   // For internal use by InputTextMultiline()
    531 };
    532 
    533 // Flags for ImGui::TreeNodeEx(), ImGui::CollapsingHeader*()
    534 enum ImGuiTreeNodeFlags_
    535 {
    536     ImGuiTreeNodeFlags_Selected             = 1 << 0,   // Draw as selected
    537     ImGuiTreeNodeFlags_Framed               = 1 << 1,   // Full colored frame (e.g. for CollapsingHeader)
    538     ImGuiTreeNodeFlags_AllowOverlapMode     = 1 << 2,   // Hit testing to allow subsequent widgets to overlap this one
    539     ImGuiTreeNodeFlags_NoTreePushOnOpen     = 1 << 3,   // Don't do a TreePush() when open (e.g. for CollapsingHeader) = no extra indent nor pushing on ID stack
    540     ImGuiTreeNodeFlags_NoAutoOpenOnLog      = 1 << 4,   // Don't automatically and temporarily open node when Logging is active (by default logging will automatically open tree nodes)
    541     ImGuiTreeNodeFlags_DefaultOpen          = 1 << 5,   // Default node to be open
    542     ImGuiTreeNodeFlags_OpenOnDoubleClick    = 1 << 6,   // Need double-click to open node
    543     ImGuiTreeNodeFlags_OpenOnArrow          = 1 << 7,   // Only open when clicking on the arrow part. If ImGuiTreeNodeFlags_OpenOnDoubleClick is also set, single-click arrow or double-click all box to open.
    544     ImGuiTreeNodeFlags_Leaf                 = 1 << 8,   // No collapsing, no arrow (use as a convenience for leaf nodes). 
    545     ImGuiTreeNodeFlags_Bullet               = 1 << 9,   // Display a bullet instead of arrow
    546     //ImGuITreeNodeFlags_SpanAllAvailWidth  = 1 << 10,  // FIXME: TODO: Extend hit box horizontally even if not framed
    547     //ImGuiTreeNodeFlags_NoScrollOnOpen     = 1 << 11,  // FIXME: TODO: Disable automatic scroll on TreePop() if node got just open and contents is not visible
    548     ImGuiTreeNodeFlags_CollapsingHeader     = ImGuiTreeNodeFlags_Framed | ImGuiTreeNodeFlags_NoAutoOpenOnLog
    549 };
    550 
    551 // Flags for ImGui::Selectable()
    552 enum ImGuiSelectableFlags_
    553 {
    554     // Default: 0
    555     ImGuiSelectableFlags_DontClosePopups    = 1 << 0,   // Clicking this don't close parent popup window
    556     ImGuiSelectableFlags_SpanAllColumns     = 1 << 1,   // Selectable frame can span all columns (text will still fit in current column)
    557     ImGuiSelectableFlags_AllowDoubleClick   = 1 << 2    // Generate press events on double clicks too
    558 };
    559 
    560 // User fill ImGuiIO.KeyMap[] array with indices into the ImGuiIO.KeysDown[512] array
    561 enum ImGuiKey_
    562 {
    563     ImGuiKey_Tab,       // for tabbing through fields
    564     ImGuiKey_LeftArrow, // for text edit
    565     ImGuiKey_RightArrow,// for text edit
    566     ImGuiKey_UpArrow,   // for text edit
    567     ImGuiKey_DownArrow, // for text edit
    568     ImGuiKey_PageUp,
    569     ImGuiKey_PageDown,
    570     ImGuiKey_Home,      // for text edit
    571     ImGuiKey_End,       // for text edit
    572     ImGuiKey_Delete,    // for text edit
    573     ImGuiKey_Backspace, // for text edit
    574     ImGuiKey_Enter,     // for text edit
    575     ImGuiKey_Escape,    // for text edit
    576     ImGuiKey_A,         // for text edit CTRL+A: select all
    577     ImGuiKey_C,         // for text edit CTRL+C: copy
    578     ImGuiKey_V,         // for text edit CTRL+V: paste
    579     ImGuiKey_X,         // for text edit CTRL+X: cut
    580     ImGuiKey_Y,         // for text edit CTRL+Y: redo
    581     ImGuiKey_Z,         // for text edit CTRL+Z: undo
    582     ImGuiKey_COUNT
    583 };
    584 
    585 // Enumeration for PushStyleColor() / PopStyleColor()
    586 enum ImGuiCol_
    587 {
    588     ImGuiCol_Text,
    589     ImGuiCol_TextDisabled,
    590     ImGuiCol_WindowBg,              // Background of normal windows
    591     ImGuiCol_ChildWindowBg,         // Background of child windows
    592     ImGuiCol_PopupBg,               // Background of popups, menus, tooltips windows
    593     ImGuiCol_Border,
    594     ImGuiCol_BorderShadow,
    595     ImGuiCol_FrameBg,               // Background of checkbox, radio button, plot, slider, text input
    596     ImGuiCol_FrameBgHovered,
    597     ImGuiCol_FrameBgActive,
    598     ImGuiCol_TitleBg,
    599     ImGuiCol_TitleBgCollapsed,
    600     ImGuiCol_TitleBgActive,
    601     ImGuiCol_MenuBarBg,
    602     ImGuiCol_ScrollbarBg,
    603     ImGuiCol_ScrollbarGrab,
    604     ImGuiCol_ScrollbarGrabHovered,
    605     ImGuiCol_ScrollbarGrabActive,
    606     ImGuiCol_ComboBg,
    607     ImGuiCol_CheckMark,
    608     ImGuiCol_SliderGrab,
    609     ImGuiCol_SliderGrabActive,
    610     ImGuiCol_Button,
    611     ImGuiCol_ButtonHovered,
    612     ImGuiCol_ButtonActive,
    613     ImGuiCol_Header,
    614     ImGuiCol_HeaderHovered,
    615     ImGuiCol_HeaderActive,
    616     ImGuiCol_Column,
    617     ImGuiCol_ColumnHovered,
    618     ImGuiCol_ColumnActive,
    619     ImGuiCol_ResizeGrip,
    620     ImGuiCol_ResizeGripHovered,
    621     ImGuiCol_ResizeGripActive,
    622     ImGuiCol_CloseButton,
    623     ImGuiCol_CloseButtonHovered,
    624     ImGuiCol_CloseButtonActive,
    625     ImGuiCol_PlotLines,
    626     ImGuiCol_PlotLinesHovered,
    627     ImGuiCol_PlotHistogram,
    628     ImGuiCol_PlotHistogramHovered,
    629     ImGuiCol_TextSelectedBg,
    630     ImGuiCol_ModalWindowDarkening,  // darken entire screen when a modal window is active
    631     ImGuiCol_COUNT
    632 };
    633 
    634 // Enumeration for PushStyleVar() / PopStyleVar()
    635 // NB: the enum only refers to fields of ImGuiStyle() which makes sense to be pushed/poped in UI code. Feel free to add others.
    636 enum ImGuiStyleVar_
    637 {
    638     ImGuiStyleVar_Alpha,               // float
    639     ImGuiStyleVar_WindowPadding,       // ImVec2
    640     ImGuiStyleVar_WindowRounding,      // float
    641     ImGuiStyleVar_WindowMinSize,       // ImVec2
    642     ImGuiStyleVar_ChildWindowRounding, // float
    643     ImGuiStyleVar_FramePadding,        // ImVec2
    644     ImGuiStyleVar_FrameRounding,       // float
    645     ImGuiStyleVar_ItemSpacing,         // ImVec2
    646     ImGuiStyleVar_ItemInnerSpacing,    // ImVec2
    647     ImGuiStyleVar_IndentSpacing,       // float
    648     ImGuiStyleVar_GrabMinSize,         // float
    649     ImGuiStyleVar_ButtonTextAlign,     // flags ImGuiAlign_*
    650     ImGuiStyleVar_Count_
    651 };
    652 
    653 // Enumeration for ColorEditMode()
    654 // FIXME-OBSOLETE: Will be replaced by future color/picker api
    655 enum ImGuiColorEditMode_
    656 {
    657     ImGuiColorEditMode_UserSelect = -2,
    658     ImGuiColorEditMode_UserSelectShowButton = -1,
    659     ImGuiColorEditMode_RGB = 0,
    660     ImGuiColorEditMode_HSV = 1,
    661     ImGuiColorEditMode_HEX = 2
    662 };
    663 
    664 // Enumeration for GetMouseCursor()
    665 enum ImGuiMouseCursor_
    666 {
    667     ImGuiMouseCursor_None = -1,
    668     ImGuiMouseCursor_Arrow = 0,
    669     ImGuiMouseCursor_TextInput,         // When hovering over InputText, etc.
    670     ImGuiMouseCursor_Move,              // Unused
    671     ImGuiMouseCursor_ResizeNS,          // Unused
    672     ImGuiMouseCursor_ResizeEW,          // When hovering over a column
    673     ImGuiMouseCursor_ResizeNESW,        // Unused
    674     ImGuiMouseCursor_ResizeNWSE,        // When hovering over the bottom-right corner of a window
    675     ImGuiMouseCursor_Count_
    676 };
    677 
    678 // Condition flags for ImGui::SetWindow***(), SetNextWindow***(), SetNextTreeNode***() functions
    679 // All those functions treat 0 as a shortcut to ImGuiSetCond_Always
    680 enum ImGuiSetCond_
    681 {
    682     ImGuiSetCond_Always        = 1 << 0, // Set the variable
    683     ImGuiSetCond_Once          = 1 << 1, // Set the variable once per runtime session (only the first call with succeed)
    684     ImGuiSetCond_FirstUseEver  = 1 << 2, // Set the variable if the window has no saved data (if doesn't exist in the .ini file)
    685     ImGuiSetCond_Appearing     = 1 << 3  // Set the variable if the window is appearing after being hidden/inactive (or the first time)
    686 };
    687 
    688 struct ImGuiStyle
    689 {
    690     float       Alpha;                      // Global alpha applies to everything in ImGui
    691     ImVec2      WindowPadding;              // Padding within a window
    692     ImVec2      WindowMinSize;              // Minimum window size
    693     float       WindowRounding;             // Radius of window corners rounding. Set to 0.0f to have rectangular windows
    694     ImVec2      WindowTitleAlign;           // Alignment for title bar text. Defaults to (0.0f,0.5f) for left-aligned,vertically centered.
    695     float       ChildWindowRounding;        // Radius of child window corners rounding. Set to 0.0f to have rectangular windows
    696     ImVec2      FramePadding;               // Padding within a framed rectangle (used by most widgets)
    697     float       FrameRounding;              // Radius of frame corners rounding. Set to 0.0f to have rectangular frame (used by most widgets).
    698     ImVec2      ItemSpacing;                // Horizontal and vertical spacing between widgets/lines
    699     ImVec2      ItemInnerSpacing;           // Horizontal and vertical spacing between within elements of a composed widget (e.g. a slider and its label)
    700     ImVec2      TouchExtraPadding;          // Expand reactive bounding box for touch-based system where touch position is not accurate enough. Unfortunately we don't sort widgets so priority on overlap will always be given to the first widget. So don't grow this too much!
    701     float       IndentSpacing;              // Horizontal indentation when e.g. entering a tree node. Generally == (FontSize + FramePadding.x*2).
    702     float       ColumnsMinSpacing;          // Minimum horizontal spacing between two columns
    703     float       ScrollbarSize;              // Width of the vertical scrollbar, Height of the horizontal scrollbar
    704     float       ScrollbarRounding;          // Radius of grab corners for scrollbar
    705     float       GrabMinSize;                // Minimum width/height of a grab box for slider/scrollbar.
    706     float       GrabRounding;               // Radius of grabs corners rounding. Set to 0.0f to have rectangular slider grabs.
    707     ImVec2      ButtonTextAlign;            // Alignment of button text when button is larger than text. Defaults to (0.5f,0.5f) for horizontally+vertically centered.
    708     ImVec2      DisplayWindowPadding;       // Window positions are clamped to be visible within the display area by at least this amount. Only covers regular windows.
    709     ImVec2      DisplaySafeAreaPadding;     // If you cannot see the edge of your screen (e.g. on a TV) increase the safe area padding. Covers popups/tooltips as well regular windows.
    710     bool        AntiAliasedLines;           // Enable anti-aliasing on lines/borders. Disable if you are really tight on CPU/GPU.
    711     bool        AntiAliasedShapes;          // Enable anti-aliasing on filled shapes (rounded rectangles, circles, etc.)
    712     float       CurveTessellationTol;       // Tessellation tolerance. Decrease for highly tessellated curves (higher quality, more polygons), increase to reduce quality.
    713     ImVec4      Colors[ImGuiCol_COUNT];
    714 
    715     IMGUI_API ImGuiStyle();
    716 };
    717 
    718 // This is where your app communicate with ImGui. Access via ImGui::GetIO().
    719 // Read 'Programmer guide' section in .cpp file for general usage.
    720 struct ImGuiIO
    721 {
    722     //------------------------------------------------------------------
    723     // Settings (fill once)                 // Default value:
    724     //------------------------------------------------------------------
    725 
    726     ImVec2        DisplaySize;              // <unset>              // Display size, in pixels. For clamping windows positions.
    727     float         DeltaTime;                // = 1.0f/60.0f         // Time elapsed since last frame, in seconds.
    728     float         IniSavingRate;            // = 5.0f               // Maximum time between saving positions/sizes to .ini file, in seconds.
    729     const char*   IniFilename;              // = "imgui.ini"        // Path to .ini file. NULL to disable .ini saving.
    730     const char*   LogFilename;              // = "imgui_log.txt"    // Path to .log file (default parameter to ImGui::LogToFile when no file is specified).
    731     float         MouseDoubleClickTime;     // = 0.30f              // Time for a double-click, in seconds.
    732     float         MouseDoubleClickMaxDist;  // = 6.0f               // Distance threshold to stay in to validate a double-click, in pixels.
    733     float         MouseDragThreshold;       // = 6.0f               // Distance threshold before considering we are dragging
    734     int           KeyMap[ImGuiKey_COUNT];   // <unset>              // Map of indices into the KeysDown[512] entries array
    735     float         KeyRepeatDelay;           // = 0.250f             // When holding a key/button, time before it starts repeating, in seconds (for buttons in Repeat mode, etc.).
    736     float         KeyRepeatRate;            // = 0.020f             // When holding a key/button, rate at which it repeats, in seconds.
    737     void*         UserData;                 // = NULL               // Store your own data for retrieval by callbacks.
    738 
    739     ImFontAtlas*  Fonts;                    // <auto>               // Load and assemble one or more fonts into a single tightly packed texture. Output to Fonts array.
    740     float         FontGlobalScale;          // = 1.0f               // Global scale all fonts
    741     bool          FontAllowUserScaling;     // = false              // Allow user scaling text of individual window with CTRL+Wheel.
    742     ImFont*       FontDefault;              // = NULL               // Font to use on NewFrame(). Use NULL to uses Fonts->Fonts[0].
    743     ImVec2        DisplayFramebufferScale;  // = (1.0f,1.0f)        // For retina display or other situations where window coordinates are different from framebuffer coordinates. User storage only, presently not used by ImGui.
    744     ImVec2        DisplayVisibleMin;        // <unset> (0.0f,0.0f)  // If you use DisplaySize as a virtual space larger than your screen, set DisplayVisibleMin/Max to the visible area.
    745     ImVec2        DisplayVisibleMax;        // <unset> (0.0f,0.0f)  // If the values are the same, we defaults to Min=(0.0f) and Max=DisplaySize
    746 
    747     // Advanced/subtle behaviors
    748     bool          OSXBehaviors;             // = defined(__APPLE__) // OS X style: Text editing cursor movement using Alt instead of Ctrl, Shortcuts using Cmd/Super instead of Ctrl, Line/Text Start and End using Cmd+Arrows instead of Home/End, Double click selects by word instead of selecting whole text, Multi-selection in lists uses Cmd/Super instead of Ctrl
    749 
    750     //------------------------------------------------------------------
    751     // User Functions
    752     //------------------------------------------------------------------
    753 
    754     // Rendering function, will be called in Render().
    755     // Alternatively you can keep this to NULL and call GetDrawData() after Render() to get the same pointer.
    756     // See example applications if you are unsure of how to implement this.
    757     void        (*RenderDrawListsFn)(ImDrawData* data);
    758 
    759     // Optional: access OS clipboard
    760     // (default to use native Win32 clipboard on Windows, otherwise uses a private clipboard. Override to access OS clipboard on other architectures)
    761     const char* (*GetClipboardTextFn)(void* user_data);
    762     void        (*SetClipboardTextFn)(void* user_data, const char* text);
    763     void*       ClipboardUserData;
    764 
    765     // Optional: override memory allocations. MemFreeFn() may be called with a NULL pointer.
    766     // (default to posix malloc/free)
    767     void*       (*MemAllocFn)(size_t sz);
    768     void        (*MemFreeFn)(void* ptr);
    769 
    770     // Optional: notify OS Input Method Editor of the screen position of your cursor for text input position (e.g. when using Japanese/Chinese IME in Windows)
    771     // (default to use native imm32 api on Windows)
    772     void        (*ImeSetInputScreenPosFn)(int x, int y);
    773     void*       ImeWindowHandle;            // (Windows) Set this to your HWND to get automatic IME cursor positioning.
    774 
    775     //------------------------------------------------------------------
    776     // Input - Fill before calling NewFrame()
    777     //------------------------------------------------------------------
    778 
    779     ImVec2      MousePos;                   // Mouse position, in pixels (set to -1,-1 if no mouse / on another screen, etc.)
    780     bool        MouseDown[5];               // Mouse buttons: left, right, middle + extras. ImGui itself mostly only uses left button (BeginPopupContext** are using right button). Others buttons allows us to track if the mouse is being used by your application + available to user as a convenience via IsMouse** API.
    781     float       MouseWheel;                 // Mouse wheel: 1 unit scrolls about 5 lines text.
    782     bool        MouseDrawCursor;            // Request ImGui to draw a mouse cursor for you (if you are on a platform without a mouse cursor).
    783     bool        KeyCtrl;                    // Keyboard modifier pressed: Control
    784     bool        KeyShift;                   // Keyboard modifier pressed: Shift
    785     bool        KeyAlt;                     // Keyboard modifier pressed: Alt
    786     bool        KeySuper;                   // Keyboard modifier pressed: Cmd/Super/Windows
    787     bool        KeysDown[512];              // Keyboard keys that are pressed (in whatever storage order you naturally have access to keyboard data)
    788     ImWchar     InputCharacters[16+1];      // List of characters input (translated by user from keypress+keyboard state). Fill using AddInputCharacter() helper.
    789 
    790     // Functions
    791     IMGUI_API void AddInputCharacter(ImWchar c);                        // Add new character into InputCharacters[]
    792     IMGUI_API void AddInputCharactersUTF8(const char* utf8_chars);      // Add new characters into InputCharacters[] from an UTF-8 string
    793     inline void    ClearInputCharacters() { InputCharacters[0] = 0; }   // Clear the text input buffer manually
    794 
    795     //------------------------------------------------------------------
    796     // Output - Retrieve after calling NewFrame()
    797     //------------------------------------------------------------------
    798 
    799     bool        WantCaptureMouse;           // Mouse is hovering a window or widget is active (= ImGui will use your mouse input). Use to hide mouse from the rest of your application
    800     bool        WantCaptureKeyboard;        // Widget is active (= ImGui will use your keyboard input). Use to hide keyboard from the rest of your application
    801     bool        WantTextInput;              // Some text input widget is active, which will read input characters from the InputCharacters array. Use to activate on screen keyboard if your system needs one
    802     float       Framerate;                  // Application framerate estimation, in frame per second. Solely for convenience. Rolling average estimation based on IO.DeltaTime over 120 frames
    803     int         MetricsAllocs;              // Number of active memory allocations
    804     int         MetricsRenderVertices;      // Vertices output during last call to Render()
    805     int         MetricsRenderIndices;       // Indices output during last call to Render() = number of triangles * 3
    806     int         MetricsActiveWindows;       // Number of visible root windows (exclude child windows)
    807     ImVec2      MouseDelta;                 // Mouse delta. Note that this is zero if either current or previous position are negative, so a disappearing/reappearing mouse won't have a huge delta for one frame.
    808 
    809     //------------------------------------------------------------------
    810     // [Private] ImGui will maintain those fields. Forward compatibility not guaranteed!
    811     //------------------------------------------------------------------
    812 
    813     ImVec2      MousePosPrev;               // Previous mouse position temporary storage (nb: not for public use, set to MousePos in NewFrame())
    814     bool        MouseClicked[5];            // Mouse button went from !Down to Down
    815     ImVec2      MouseClickedPos[5];         // Position at time of clicking
    816     float       MouseClickedTime[5];        // Time of last click (used to figure out double-click)
    817     bool        MouseDoubleClicked[5];      // Has mouse button been double-clicked?
    818     bool        MouseReleased[5];           // Mouse button went from Down to !Down
    819     bool        MouseDownOwned[5];          // Track if button was clicked inside a window. We don't request mouse capture from the application if click started outside ImGui bounds.
    820     float       MouseDownDuration[5];       // Duration the mouse button has been down (0.0f == just clicked)
    821     float       MouseDownDurationPrev[5];   // Previous time the mouse button has been down
    822     float       MouseDragMaxDistanceSqr[5]; // Squared maximum distance of how much mouse has traveled from the click point
    823     float       KeysDownDuration[512];      // Duration the keyboard key has been down (0.0f == just pressed)
    824     float       KeysDownDurationPrev[512];  // Previous duration the key has been down
    825 
    826     IMGUI_API   ImGuiIO();
    827 };
    828 
    829 //-----------------------------------------------------------------------------
    830 // Helpers
    831 //-----------------------------------------------------------------------------
    832 
    833 // Lightweight std::vector<> like class to avoid dragging dependencies (also: windows implementation of STL with debug enabled is absurdly slow, so let's bypass it so our code runs fast in debug).
    834 // Our implementation does NOT call c++ constructors because we don't use them in ImGui. Don't use this class as a straight std::vector replacement in your code!
    835 template<typename T>
    836 class ImVector
    837 {
    838 public:
    839     int                         Size;
    840     int                         Capacity;
    841     T*                          Data;
    842 
    843     typedef T                   value_type;
    844     typedef value_type*         iterator;
    845     typedef const value_type*   const_iterator;
    846 
    847     ImVector()                  { Size = Capacity = 0; Data = NULL; }
    848     ~ImVector()                 { if (Data) ImGui::MemFree(Data); }
    849 
    850     inline bool                 empty() const                   { return Size == 0; }
    851     inline int                  size() const                    { return Size; }
    852     inline int                  capacity() const                { return Capacity; }
    853 
    854     inline value_type&          operator[](int i)               { IM_ASSERT(i < Size); return Data[i]; }
    855     inline const value_type&    operator[](int i) const         { IM_ASSERT(i < Size); return Data[i]; }
    856 
    857     inline void                 clear()                         { if (Data) { Size = Capacity = 0; ImGui::MemFree(Data); Data = NULL; } }
    858     inline iterator             begin()                         { return Data; }
    859     inline const_iterator       begin() const                   { return Data; }
    860     inline iterator             end()                           { return Data + Size; }
    861     inline const_iterator       end() const                     { return Data + Size; }
    862     inline value_type&          front()                         { IM_ASSERT(Size > 0); return Data[0]; }
    863     inline const value_type&    front() const                   { IM_ASSERT(Size > 0); return Data[0]; }
    864     inline value_type&          back()                          { IM_ASSERT(Size > 0); return Data[Size-1]; }
    865     inline const value_type&    back() const                    { IM_ASSERT(Size > 0); return Data[Size-1]; }
    866     inline void                 swap(ImVector<T>& rhs)          { int rhs_size = rhs.Size; rhs.Size = Size; Size = rhs_size; int rhs_cap = rhs.Capacity; rhs.Capacity = Capacity; Capacity = rhs_cap; value_type* rhs_data = rhs.Data; rhs.Data = Data; Data = rhs_data; }
    867 
    868     inline int                  _grow_capacity(int new_size)    { int new_capacity = Capacity ? (Capacity + Capacity/2) : 8; return new_capacity > new_size ? new_capacity : new_size; }
    869 
    870     inline void                 resize(int new_size)            { if (new_size > Capacity) reserve(_grow_capacity(new_size)); Size = new_size; }
    871     inline void                 reserve(int new_capacity)
    872     {
    873         if (new_capacity <= Capacity) return;
    874         T* new_data = (value_type*)ImGui::MemAlloc((size_t)new_capacity * sizeof(value_type));
    875         if (Data)
    876             memcpy(new_data, Data, (size_t)Size * sizeof(value_type));
    877         ImGui::MemFree(Data);
    878         Data = new_data;
    879         Capacity = new_capacity;
    880     }
    881 
    882     inline void                 push_back(const value_type& v)  { if (Size == Capacity) reserve(_grow_capacity(Size+1)); Data[Size++] = v; }
    883     inline void                 pop_back()                      { IM_ASSERT(Size > 0); Size--; }
    884 
    885     inline iterator             erase(const_iterator it)        { IM_ASSERT(it >= Data && it < Data+Size); const ptrdiff_t off = it - Data; memmove(Data + off, Data + off + 1, ((size_t)Size - (size_t)off - 1) * sizeof(value_type)); Size--; return Data + off; }
    886     inline iterator             insert(const_iterator it, const value_type& v)  { IM_ASSERT(it >= Data && it <= Data+Size); const ptrdiff_t off = it - Data; if (Size == Capacity) reserve(Capacity ? Capacity * 2 : 4); if (off < (int)Size) memmove(Data + off + 1, Data + off, ((size_t)Size - (size_t)off) * sizeof(value_type)); Data[off] = v; Size++; return Data + off; }
    887 };
    888 
    889 // Helper: execute a block of code at maximum once a frame
    890 // Convenient if you want to quickly create an UI within deep-nested code that runs multiple times every frame.
    891 // Usage:
    892 //   IMGUI_ONCE_UPON_A_FRAME
    893 //   {
    894 //      // code block will be executed one per frame
    895 //   }
    896 // Attention! the macro expands into 2 statement so make sure you don't use it within e.g. an if() statement without curly braces.
    897 #define IMGUI_ONCE_UPON_A_FRAME    static ImGuiOnceUponAFrame imgui_oaf##__LINE__; if (imgui_oaf##__LINE__)
    898 struct ImGuiOnceUponAFrame
    899 {
    900     ImGuiOnceUponAFrame() { RefFrame = -1; }
    901     mutable int RefFrame;
    902     operator bool() const { int current_frame = ImGui::GetFrameCount(); if (RefFrame == current_frame) return false; RefFrame = current_frame; return true; }
    903 };
    904 
    905 // Helper: Parse and apply text filters. In format "aaaaa[,bbbb][,ccccc]"
    906 struct ImGuiTextFilter
    907 {
    908     struct TextRange
    909     {
    910         const char* b;
    911         const char* e;
    912 
    913         TextRange() { b = e = NULL; }
    914         TextRange(const char* _b, const char* _e) { b = _b; e = _e; }
    915         const char* begin() const { return b; }
    916         const char* end() const { return e; }
    917         bool empty() const { return b == e; }
    918         char front() const { return *b; }
    919         static bool is_blank(char c) { return c == ' ' || c == '\t'; }
    920         void trim_blanks() { while (b < e && is_blank(*b)) b++; while (e > b && is_blank(*(e-1))) e--; }
    921         IMGUI_API void split(char separator, ImVector<TextRange>& out);
    922     };
    923 
    924     char                InputBuf[256];
    925     ImVector<TextRange> Filters;
    926     int                 CountGrep;
    927 
    928     ImGuiTextFilter(const char* default_filter = "");
    929     ~ImGuiTextFilter() {}
    930     void                Clear() { InputBuf[0] = 0; Build(); }
    931     bool                Draw(const char* label = "Filter (inc,-exc)", float width = 0.0f);    // Helper calling InputText+Build
    932     bool                PassFilter(const char* text, const char* text_end = NULL) const;
    933     bool                IsActive() const { return !Filters.empty(); }
    934     IMGUI_API void      Build();
    935 };
    936 
    937 // Helper: Text buffer for logging/accumulating text
    938 struct ImGuiTextBuffer
    939 {
    940     ImVector<char>      Buf;
    941 
    942     ImGuiTextBuffer()   { Buf.push_back(0); }
    943     inline char         operator[](int i) { return Buf.Data[i]; }
    944     const char*         begin() const { return &Buf.front(); }
    945     const char*         end() const { return &Buf.back(); }      // Buf is zero-terminated, so end() will point on the zero-terminator
    946     int                 size() const { return Buf.Size - 1; }
    947     bool                empty() { return Buf.Size <= 1; }
    948     void                clear() { Buf.clear(); Buf.push_back(0); }
    949     const char*         c_str() const { return Buf.Data; }
    950     IMGUI_API void      append(const char* fmt, ...) IM_PRINTFARGS(2);
    951     IMGUI_API void      appendv(const char* fmt, va_list args);
    952 };
    953 
    954 // Helper: Simple Key->value storage
    955 // Typically you don't have to worry about this since a storage is held within each Window.
    956 // We use it to e.g. store collapse state for a tree (Int 0/1), store color edit options.
    957 // You can use it as custom user storage for temporary values.
    958 // Declare your own storage if:
    959 // - You want to manipulate the open/close state of a particular sub-tree in your interface (tree node uses Int 0/1 to store their state).
    960 // - You want to store custom debug data easily without adding or editing structures in your code.
    961 // Types are NOT stored, so it is up to you to make sure your Key don't collide with different types.
    962 struct ImGuiStorage
    963 {
    964     struct Pair
    965     {
    966         ImGuiID key;
    967         union { int val_i; float val_f; void* val_p; };
    968         Pair(ImGuiID _key, int _val_i) { key = _key; val_i = _val_i; }
    969         Pair(ImGuiID _key, float _val_f) { key = _key; val_f = _val_f; }
    970         Pair(ImGuiID _key, void* _val_p) { key = _key; val_p = _val_p; }
    971     };
    972     ImVector<Pair>      Data;
    973 
    974     // - Get***() functions find pair, never add/allocate. Pairs are sorted so a query is O(log N)
    975     // - Set***() functions find pair, insertion on demand if missing.
    976     // - Sorted insertion is costly, paid once. A typical frame shouldn't need to insert any new pair.
    977     IMGUI_API void      Clear();
    978     IMGUI_API int       GetInt(ImGuiID key, int default_val = 0) const;
    979     IMGUI_API void      SetInt(ImGuiID key, int val);
    980     IMGUI_API bool      GetBool(ImGuiID key, bool default_val = false) const;
    981     IMGUI_API void      SetBool(ImGuiID key, bool val);
    982     IMGUI_API float     GetFloat(ImGuiID key, float default_val = 0.0f) const;
    983     IMGUI_API void      SetFloat(ImGuiID key, float val);
    984     IMGUI_API void*     GetVoidPtr(ImGuiID key) const; // default_val is NULL
    985     IMGUI_API void      SetVoidPtr(ImGuiID key, void* val);
    986 
    987     // - Get***Ref() functions finds pair, insert on demand if missing, return pointer. Useful if you intend to do Get+Set.
    988     // - References are only valid until a new value is added to the storage. Calling a Set***() function or a Get***Ref() function invalidates the pointer.
    989     // - A typical use case where this is convenient for quick hacking (e.g. add storage during a live Edit&Continue session if you can't modify existing struct)
    990     //      float* pvar = ImGui::GetFloatRef(key); ImGui::SliderFloat("var", pvar, 0, 100.0f); some_var += *pvar;
    991     IMGUI_API int*      GetIntRef(ImGuiID key, int default_val = 0);
    992     IMGUI_API bool*     GetBoolRef(ImGuiID key, bool default_val = false);
    993     IMGUI_API float*    GetFloatRef(ImGuiID key, float default_val = 0.0f);
    994     IMGUI_API void**    GetVoidPtrRef(ImGuiID key, void* default_val = NULL);
    995 
    996     // Use on your own storage if you know only integer are being stored (open/close all tree nodes)
    997     IMGUI_API void      SetAllInt(int val);
    998 };
    999 
   1000 // Shared state of InputText(), passed to callback when a ImGuiInputTextFlags_Callback* flag is used and the corresponding callback is triggered.
   1001 struct ImGuiTextEditCallbackData
   1002 {
   1003     ImGuiInputTextFlags EventFlag;      // One of ImGuiInputTextFlags_Callback* // Read-only
   1004     ImGuiInputTextFlags Flags;          // What user passed to InputText()      // Read-only
   1005     void*               UserData;       // What user passed to InputText()      // Read-only
   1006     bool                ReadOnly;       // Read-only mode                       // Read-only
   1007 
   1008     // CharFilter event:
   1009     ImWchar             EventChar;      // Character input                      // Read-write (replace character or set to zero)
   1010 
   1011     // Completion,History,Always events:
   1012     // If you modify the buffer contents make sure you update 'BufTextLen' and set 'BufDirty' to true.
   1013     ImGuiKey            EventKey;       // Key pressed (Up/Down/TAB)            // Read-only
   1014     char*               Buf;            // Current text buffer                  // Read-write (pointed data only, can't replace the actual pointer)
   1015     int                 BufTextLen;     // Current text length in bytes         // Read-write
   1016     int                 BufSize;        // Maximum text length in bytes         // Read-only
   1017     bool                BufDirty;       // Set if you modify Buf/BufTextLen!!   // Write
   1018     int                 CursorPos;      //                                      // Read-write
   1019     int                 SelectionStart; //                                      // Read-write (== to SelectionEnd when no selection)
   1020     int                 SelectionEnd;   //                                      // Read-write
   1021 
   1022     // NB: Helper functions for text manipulation. Calling those function loses selection.
   1023     IMGUI_API void    DeleteChars(int pos, int bytes_count);
   1024     IMGUI_API void    InsertChars(int pos, const char* text, const char* text_end = NULL);
   1025     bool    HasSelection() const { return SelectionStart != SelectionEnd; }
   1026 };
   1027 
   1028 // Resizing callback data to apply custom constraint. As enabled by SetNextWindowSizeConstraints(). Callback is called during the next Begin().
   1029 // NB: For basic min/max size constraint on each axis you don't need to use the callback! The SetNextWindowSizeConstraints() parameters are enough.
   1030 struct ImGuiSizeConstraintCallbackData
   1031 {
   1032     void*   UserData;       // Read-only.   What user passed to SetNextWindowSizeConstraints()
   1033     ImVec2  Pos;            // Read-only.	Window position, for reference.
   1034     ImVec2  CurrentSize;    // Read-only.	Current window size.
   1035     ImVec2  DesiredSize;    // Read-write.  Desired size, based on user's mouse position. Write to this field to restrain resizing.
   1036 };
   1037 
   1038 // Helpers macros to generate 32-bits encoded colors
   1039 #ifdef IMGUI_USE_BGRA_PACKED_COLOR
   1040 #define IM_COL32_R_SHIFT    16
   1041 #define IM_COL32_G_SHIFT    8
   1042 #define IM_COL32_B_SHIFT    0
   1043 #define IM_COL32_A_SHIFT    24
   1044 #define IM_COL32_A_MASK     0xFF000000
   1045 #else
   1046 #define IM_COL32_R_SHIFT    0
   1047 #define IM_COL32_G_SHIFT    8
   1048 #define IM_COL32_B_SHIFT    16
   1049 #define IM_COL32_A_SHIFT    24
   1050 #define IM_COL32_A_MASK     0xFF000000
   1051 #endif
   1052 #define IM_COL32(R,G,B,A)    (((ImU32)(A)<<IM_COL32_A_SHIFT) | ((ImU32)(B)<<IM_COL32_B_SHIFT) | ((ImU32)(G)<<IM_COL32_G_SHIFT) | ((ImU32)(R)<<IM_COL32_R_SHIFT))
   1053 #define IM_COL32_WHITE       IM_COL32(255,255,255,255)  // Opaque white = 0xFFFFFFFF
   1054 #define IM_COL32_BLACK       IM_COL32(0,0,0,255)        // Opaque black
   1055 #define IM_COL32_BLACK_TRANS IM_COL32(0,0,0,0)          // Transparent black = 0x00000000
   1056 
   1057 // ImColor() helper to implicity converts colors to either ImU32 (packed 4x1 byte) or ImVec4 (4x1 float)
   1058 // Prefer using IM_COL32() macros if you want a guaranteed compile-time ImU32 for usage with ImDrawList API.
   1059 // **Avoid storing ImColor! Store either u32 of ImVec4. This is not a full-featured color class.
   1060 // **None of the ImGui API are using ImColor directly but you can use it as a convenience to pass colors in either ImU32 or ImVec4 formats.
   1061 struct ImColor
   1062 {
   1063     ImVec4              Value;
   1064 
   1065     ImColor()                                                       { Value.x = Value.y = Value.z = Value.w = 0.0f; }
   1066     ImColor(int r, int g, int b, int a = 255)                       { float sc = 1.0f/255.0f; Value.x = (float)r * sc; Value.y = (float)g * sc; Value.z = (float)b * sc; Value.w = (float)a * sc; }
   1067     ImColor(ImU32 rgba)                                             { float sc = 1.0f/255.0f; Value.x = (float)((rgba>>IM_COL32_R_SHIFT)&0xFF) * sc; Value.y = (float)((rgba>>IM_COL32_G_SHIFT)&0xFF) * sc; Value.z = (float)((rgba>>IM_COL32_B_SHIFT)&0xFF) * sc; Value.w = (float)((rgba>>IM_COL32_A_SHIFT)&0xFF) * sc; }
   1068     ImColor(float r, float g, float b, float a = 1.0f)              { Value.x = r; Value.y = g; Value.z = b; Value.w = a; }
   1069     ImColor(const ImVec4& col)                                      { Value = col; }
   1070     inline operator ImU32() const                                   { return ImGui::ColorConvertFloat4ToU32(Value); }
   1071     inline operator ImVec4() const                                  { return Value; }
   1072 
   1073     inline void    SetHSV(float h, float s, float v, float a = 1.0f){ ImGui::ColorConvertHSVtoRGB(h, s, v, Value.x, Value.y, Value.z); Value.w = a; }
   1074 
   1075     static ImColor HSV(float h, float s, float v, float a = 1.0f)   { float r,g,b; ImGui::ColorConvertHSVtoRGB(h, s, v, r, g, b); return ImColor(r,g,b,a); }
   1076 };
   1077 
   1078 // Helper: Manually clip large list of items.
   1079 // If you are submitting lots of evenly spaced items and you have a random access to the list, you can perform coarse clipping based on visibility to save yourself from processing those items at all.
   1080 // The clipper calculates the range of visible items and advance the cursor to compensate for the non-visible items we have skipped. 
   1081 // ImGui already clip items based on their bounds but it needs to measure text size to do so. Coarse clipping before submission makes this cost and your own data fetching/submission cost null.
   1082 // Usage:
   1083 //     ImGuiListClipper clipper(1000);  // we have 1000 elements, evenly spaced.
   1084 //     while (clipper.Step())
   1085 //         for (int i = clipper.DisplayStart; i < clipper.DisplayEnd; i++)
   1086 //             ImGui::Text("line number %d", i);
   1087 // - Step 0: the clipper let you process the first element, regardless of it being visible or not, so we can measure the element height (step skipped if we passed a known height as second arg to constructor).
   1088 // - Step 1: the clipper infer height from first element, calculate the actual range of elements to display, and position the cursor before the first element.
   1089 // - (Step 2: dummy step only required if an explicit items_height was passed to constructor or Begin() and user call Step(). Does nothing and switch to Step 3.)
   1090 // - Step 3: the clipper validate that we have reached the expected Y position (corresponding to element DisplayEnd), advance the cursor to the end of the list and then returns 'false' to end the loop.
   1091 struct ImGuiListClipper
   1092 {
   1093     float   StartPosY;
   1094     float   ItemsHeight;
   1095     int     ItemsCount, StepNo, DisplayStart, DisplayEnd;
   1096 
   1097     // items_count:  Use -1 to ignore (you can call Begin later). Use INT_MAX if you don't know how many items you have (in which case the cursor won't be advanced in the final step).
   1098     // items_height: Use -1.0f to be calculated automatically on first step. Otherwise pass in the distance between your items, typically GetTextLineHeightWithSpacing() or GetItemsLineHeightWithSpacing().
   1099     // If you don't specify an items_height, you NEED to call Step(). If you specify items_height you may call the old Begin()/End() api directly, but prefer calling Step().
   1100     ImGuiListClipper(int items_count = -1, float items_height = -1.0f)  { Begin(items_count, items_height); } // NB: Begin() initialize every fields (as we allow user to call Begin/End multiple times on a same instance if they want).
   1101     ~ImGuiListClipper()                                                 { IM_ASSERT(ItemsCount == -1); }      // Assert if user forgot to call End() or Step() until false.
   1102 
   1103     IMGUI_API bool Step();                                              // Call until it returns false. The DisplayStart/DisplayEnd fields will be set and you can process/draw those items.
   1104     IMGUI_API void Begin(int items_count, float items_height = -1.0f);  // Automatically called by constructor if you passed 'items_count' or by Step() in Step 1.
   1105     IMGUI_API void End();                                               // Automatically called on the last call of Step() that returns false.
   1106 };
   1107 
   1108 //-----------------------------------------------------------------------------
   1109 // Draw List
   1110 // Hold a series of drawing commands. The user provides a renderer for ImDrawData which essentially contains an array of ImDrawList.
   1111 //-----------------------------------------------------------------------------
   1112 
   1113 // Draw callbacks for advanced uses.
   1114 // NB- You most likely do NOT need to use draw callbacks just to create your own widget or customized UI rendering (you can poke into the draw list for that)
   1115 // Draw callback may be useful for example, A) Change your GPU render state, B) render a complex 3D scene inside a UI element (without an intermediate texture/render target), etc.
   1116 // The expected behavior from your rendering function is 'if (cmd.UserCallback != NULL) cmd.UserCallback(parent_list, cmd); else RenderTriangles()'
   1117 typedef void (*ImDrawCallback)(const ImDrawList* parent_list, const ImDrawCmd* cmd);
   1118 
   1119 // Typically, 1 command = 1 gpu draw call (unless command is a callback)
   1120 struct ImDrawCmd
   1121 {
   1122     unsigned int    ElemCount;              // Number of indices (multiple of 3) to be rendered as triangles. Vertices are stored in the callee ImDrawList's vtx_buffer[] array, indices in idx_buffer[].
   1123     ImVec4          ClipRect;               // Clipping rectangle (x1, y1, x2, y2)
   1124     ImTextureID     TextureId;              // User-provided texture ID. Set by user in ImfontAtlas::SetTexID() for fonts or passed to Image*() functions. Ignore if never using images or multiple fonts atlas.
   1125     ImDrawCallback  UserCallback;           // If != NULL, call the function instead of rendering the vertices. clip_rect and texture_id will be set normally.
   1126     void*           UserCallbackData;       // The draw callback code can access this.
   1127 
   1128     ImDrawCmd() { ElemCount = 0; ClipRect.x = ClipRect.y = -8192.0f; ClipRect.z = ClipRect.w = +8192.0f; TextureId = NULL; UserCallback = NULL; UserCallbackData = NULL; }
   1129 };
   1130 
   1131 // Vertex index (override with '#define ImDrawIdx unsigned int' inside in imconfig.h)
   1132 #ifndef ImDrawIdx
   1133 typedef unsigned short ImDrawIdx;
   1134 #endif
   1135 
   1136 // Vertex layout
   1137 #ifndef IMGUI_OVERRIDE_DRAWVERT_STRUCT_LAYOUT
   1138 struct ImDrawVert
   1139 {
   1140     ImVec2  pos;
   1141     ImVec2  uv;
   1142     ImU32   col;
   1143 };
   1144 #else
   1145 // You can override the vertex format layout by defining IMGUI_OVERRIDE_DRAWVERT_STRUCT_LAYOUT in imconfig.h
   1146 // The code expect ImVec2 pos (8 bytes), ImVec2 uv (8 bytes), ImU32 col (4 bytes), but you can re-order them or add other fields as needed to simplify integration in your engine.
   1147 // The type has to be described within the macro (you can either declare the struct or use a typedef)
   1148 IMGUI_OVERRIDE_DRAWVERT_STRUCT_LAYOUT;
   1149 #endif
   1150 
   1151 // Draw channels are used by the Columns API to "split" the render list into different channels while building, so items of each column can be batched together.
   1152 // You can also use them to simulate drawing layers and submit primitives in a different order than how they will be rendered.
   1153 struct ImDrawChannel
   1154 {
   1155     ImVector<ImDrawCmd>     CmdBuffer;
   1156     ImVector<ImDrawIdx>     IdxBuffer;
   1157 };
   1158 
   1159 // Draw command list
   1160 // This is the low-level list of polygons that ImGui functions are filling. At the end of the frame, all command lists are passed to your ImGuiIO::RenderDrawListFn function for rendering.
   1161 // At the moment, each ImGui window contains its own ImDrawList but they could potentially be merged in the future.
   1162 // If you want to add custom rendering within a window, you can use ImGui::GetWindowDrawList() to access the current draw list and add your own primitives.
   1163 // You can interleave normal ImGui:: calls and adding primitives to the current draw list.
   1164 // All positions are in screen coordinates (0,0=top-left, 1 pixel per unit). Primitives are always added to the list and not culled (culling is done at render time and at a higher-level by ImGui:: functions).
   1165 struct ImDrawList
   1166 {
   1167     // This is what you have to render
   1168     ImVector<ImDrawCmd>     CmdBuffer;          // Commands. Typically 1 command = 1 gpu draw call.
   1169     ImVector<ImDrawIdx>     IdxBuffer;          // Index buffer. Each command consume ImDrawCmd::ElemCount of those
   1170     ImVector<ImDrawVert>    VtxBuffer;          // Vertex buffer.
   1171 
   1172     // [Internal, used while building lists]
   1173     const char*             _OwnerName;         // Pointer to owner window's name for debugging
   1174     unsigned int            _VtxCurrentIdx;     // [Internal] == VtxBuffer.Size
   1175     ImDrawVert*             _VtxWritePtr;       // [Internal] point within VtxBuffer.Data after each add command (to avoid using the ImVector<> operators too much)
   1176     ImDrawIdx*              _IdxWritePtr;       // [Internal] point within IdxBuffer.Data after each add command (to avoid using the ImVector<> operators too much)
   1177     ImVector<ImVec4>        _ClipRectStack;     // [Internal]
   1178     ImVector<ImTextureID>   _TextureIdStack;    // [Internal]
   1179     ImVector<ImVec2>        _Path;              // [Internal] current path building
   1180     int                     _ChannelsCurrent;   // [Internal] current channel number (0)
   1181     int                     _ChannelsCount;     // [Internal] number of active channels (1+)
   1182     ImVector<ImDrawChannel> _Channels;          // [Internal] draw channels for columns API (not resized down so _ChannelsCount may be smaller than _Channels.Size)
   1183 
   1184     ImDrawList()  { _OwnerName = NULL; Clear(); }
   1185     ~ImDrawList() { ClearFreeMemory(); }
   1186     IMGUI_API void  PushClipRect(ImVec2 clip_rect_min, ImVec2 clip_rect_max, bool intersect_with_current_clip_rect = false);  // Render-level scissoring. This is passed down to your render function but not used for CPU-side coarse clipping. Prefer using higher-level ImGui::PushClipRect() to affect logic (hit-testing and widget culling)
   1187     IMGUI_API void  PushClipRectFullScreen();
   1188     IMGUI_API void  PopClipRect();
   1189     IMGUI_API void  PushTextureID(const ImTextureID& texture_id);
   1190     IMGUI_API void  PopTextureID();
   1191 
   1192     // Primitives
   1193     IMGUI_API void  AddLine(const ImVec2& a, const ImVec2& b, ImU32 col, float thickness = 1.0f);
   1194     IMGUI_API void  AddRect(const ImVec2& a, const ImVec2& b, ImU32 col, float rounding = 0.0f, int rounding_corners_flags = ~0, float thickness = 1.0f);   // a: upper-left, b: lower-right, rounding_corners_flags: 4-bits corresponding to which corner to round
   1195     IMGUI_API void  AddRectFilled(const ImVec2& a, const ImVec2& b, ImU32 col, float rounding = 0.0f, int rounding_corners_flags = ~0);                     // a: upper-left, b: lower-right
   1196     IMGUI_API void  AddRectFilledMultiColor(const ImVec2& a, const ImVec2& b, ImU32 col_upr_left, ImU32 col_upr_right, ImU32 col_bot_right, ImU32 col_bot_left);
   1197     IMGUI_API void  AddQuad(const ImVec2& a, const ImVec2& b, const ImVec2& c, const ImVec2& d, ImU32 col, float thickness = 1.0f);
   1198     IMGUI_API void  AddQuadFilled(const ImVec2& a, const ImVec2& b, const ImVec2& c, const ImVec2& d, ImU32 col);
   1199     IMGUI_API void  AddTriangle(const ImVec2& a, const ImVec2& b, const ImVec2& c, ImU32 col, float thickness = 1.0f);
   1200     IMGUI_API void  AddTriangleFilled(const ImVec2& a, const ImVec2& b, const ImVec2& c, ImU32 col);
   1201     IMGUI_API void  AddCircle(const ImVec2& centre, float radius, ImU32 col, int num_segments = 12, float thickness = 1.0f);
   1202     IMGUI_API void  AddCircleFilled(const ImVec2& centre, float radius, ImU32 col, int num_segments = 12);
   1203     IMGUI_API void  AddText(const ImVec2& pos, ImU32 col, const char* text_begin, const char* text_end = NULL);
   1204     IMGUI_API void  AddText(const ImFont* font, float font_size, const ImVec2& pos, ImU32 col, const char* text_begin, const char* text_end = NULL, float wrap_width = 0.0f, const ImVec4* cpu_fine_clip_rect = NULL);
   1205     IMGUI_API void  AddImage(ImTextureID user_texture_id, const ImVec2& a, const ImVec2& b, const ImVec2& uv_a = ImVec2(0,0), const ImVec2& uv_b = ImVec2(1,1), ImU32 col = 0xFFFFFFFF);
   1206     IMGUI_API void  AddImageQuad(ImTextureID user_texture_id, const ImVec2& a, const ImVec2& b, const ImVec2& c, const ImVec2& d, const ImVec2& uv_a = ImVec2(0,0), const ImVec2& uv_b = ImVec2(1,0), const ImVec2& uv_c = ImVec2(1,1), const ImVec2& uv_d = ImVec2(0,1), ImU32 col = 0xFFFFFFFF);
   1207     IMGUI_API void  AddPolyline(const ImVec2* points, const int num_points, ImU32 col, bool closed, float thickness, bool anti_aliased);
   1208     IMGUI_API void  AddConvexPolyFilled(const ImVec2* points, const int num_points, ImU32 col, bool anti_aliased);
   1209     IMGUI_API void  AddBezierCurve(const ImVec2& pos0, const ImVec2& cp0, const ImVec2& cp1, const ImVec2& pos1, ImU32 col, float thickness, int num_segments = 0);
   1210 
   1211     // Stateful path API, add points then finish with PathFill() or PathStroke()
   1212     inline    void  PathClear()                                                 { _Path.resize(0); }
   1213     inline    void  PathLineTo(const ImVec2& pos)                               { _Path.push_back(pos); }
   1214     inline    void  PathLineToMergeDuplicate(const ImVec2& pos)                 { if (_Path.Size == 0 || memcmp(&_Path[_Path.Size-1], &pos, 8) != 0) _Path.push_back(pos); }
   1215     inline    void  PathFillConvex(ImU32 col)                                   { AddConvexPolyFilled(_Path.Data, _Path.Size, col, true); PathClear(); }
   1216     inline    void  PathStroke(ImU32 col, bool closed, float thickness = 1.0f)  { AddPolyline(_Path.Data, _Path.Size, col, closed, thickness, true); PathClear(); }
   1217     IMGUI_API void  PathArcTo(const ImVec2& centre, float radius, float a_min, float a_max, int num_segments = 10);
   1218     IMGUI_API void  PathArcToFast(const ImVec2& centre, float radius, int a_min_of_12, int a_max_of_12);                                // Use precomputed angles for a 12 steps circle
   1219     IMGUI_API void  PathBezierCurveTo(const ImVec2& p1, const ImVec2& p2, const ImVec2& p3, int num_segments = 0);
   1220     IMGUI_API void  PathRect(const ImVec2& rect_min, const ImVec2& rect_max, float rounding = 0.0f, int rounding_corners_flags = ~0);   // rounding_corners_flags: 4-bits corresponding to which corner to round
   1221 
   1222     // Channels
   1223     // - Use to simulate layers. By switching channels to can render out-of-order (e.g. submit foreground primitives before background primitives)
   1224     // - Use to minimize draw calls (e.g. if going back-and-forth between multiple non-overlapping clipping rectangles, prefer to append into separate channels then merge at the end)
   1225     IMGUI_API void  ChannelsSplit(int channels_count);
   1226     IMGUI_API void  ChannelsMerge();
   1227     IMGUI_API void  ChannelsSetCurrent(int channel_index);
   1228 
   1229     // Advanced
   1230     IMGUI_API void  AddCallback(ImDrawCallback callback, void* callback_data);  // Your rendering function must check for 'UserCallback' in ImDrawCmd and call the function instead of rendering triangles.
   1231     IMGUI_API void  AddDrawCmd();                                               // This is useful if you need to forcefully create a new draw call (to allow for dependent rendering / blending). Otherwise primitives are merged into the same draw-call as much as possible
   1232 
   1233     // Internal helpers
   1234     // NB: all primitives needs to be reserved via PrimReserve() beforehand!
   1235     IMGUI_API void  Clear();
   1236     IMGUI_API void  ClearFreeMemory();
   1237     IMGUI_API void  PrimReserve(int idx_count, int vtx_count);
   1238     IMGUI_API void  PrimRect(const ImVec2& a, const ImVec2& b, ImU32 col);      // Axis aligned rectangle (composed of two triangles)
   1239     IMGUI_API void  PrimRectUV(const ImVec2& a, const ImVec2& b, const ImVec2& uv_a, const ImVec2& uv_b, ImU32 col);
   1240     IMGUI_API void  PrimQuadUV(const ImVec2& a, const ImVec2& b, const ImVec2& c, const ImVec2& d, const ImVec2& uv_a, const ImVec2& uv_b, const ImVec2& uv_c, const ImVec2& uv_d, ImU32 col);
   1241     inline    void  PrimWriteVtx(const ImVec2& pos, const ImVec2& uv, ImU32 col){ _VtxWritePtr->pos = pos; _VtxWritePtr->uv = uv; _VtxWritePtr->col = col; _VtxWritePtr++; _VtxCurrentIdx++; }
   1242     inline    void  PrimWriteIdx(ImDrawIdx idx)                                 { *_IdxWritePtr = idx; _IdxWritePtr++; }
   1243     inline    void  PrimVtx(const ImVec2& pos, const ImVec2& uv, ImU32 col)     { PrimWriteIdx((ImDrawIdx)_VtxCurrentIdx); PrimWriteVtx(pos, uv, col); }
   1244     IMGUI_API void  UpdateClipRect();
   1245     IMGUI_API void  UpdateTextureID();
   1246 };
   1247 
   1248 // All draw data to render an ImGui frame
   1249 struct ImDrawData
   1250 {
   1251     bool            Valid;                  // Only valid after Render() is called and before the next NewFrame() is called.
   1252     ImDrawList**    CmdLists;
   1253     int             CmdListsCount;
   1254     int             TotalVtxCount;          // For convenience, sum of all cmd_lists vtx_buffer.Size
   1255     int             TotalIdxCount;          // For convenience, sum of all cmd_lists idx_buffer.Size
   1256 
   1257     // Functions
   1258     ImDrawData() { Valid = false; CmdLists = NULL; CmdListsCount = TotalVtxCount = TotalIdxCount = 0; }
   1259     IMGUI_API void DeIndexAllBuffers();               // For backward compatibility: convert all buffers from indexed to de-indexed, in case you cannot render indexed. Note: this is slow and most likely a waste of resources. Always prefer indexed rendering!
   1260     IMGUI_API void ScaleClipRects(const ImVec2& sc);  // Helper to scale the ClipRect field of each ImDrawCmd. Use if your final output buffer is at a different scale than ImGui expects, or if there is a difference between your window resolution and framebuffer resolution.
   1261 };
   1262 
   1263 struct ImFontConfig
   1264 {
   1265     void*           FontData;                   //          // TTF data
   1266     int             FontDataSize;               //          // TTF data size
   1267     bool            FontDataOwnedByAtlas;       // true     // TTF data ownership taken by the container ImFontAtlas (will delete memory itself). Set to true
   1268     int             FontNo;                     // 0        // Index of font within TTF file
   1269     float           SizePixels;                 //          // Size in pixels for rasterizer
   1270     int             OversampleH, OversampleV;   // 3, 1     // Rasterize at higher quality for sub-pixel positioning. We don't use sub-pixel positions on the Y axis.
   1271     bool            PixelSnapH;                 // false    // Align every glyph to pixel boundary. Useful e.g. if you are merging a non-pixel aligned font with the default font. If enabled, you can set OversampleH/V to 1.
   1272     ImVec2          GlyphExtraSpacing;          // 0, 0     // Extra spacing (in pixels) between glyphs
   1273     ImVec2          GlyphOffset;                // 0, 0     // Offset all glyphs from this font input
   1274     const ImWchar*  GlyphRanges;                //          // Pointer to a user-provided list of Unicode range (2 value per range, values are inclusive, zero-terminated list). THE ARRAY DATA NEEDS TO PERSIST AS LONG AS THE FONT IS ALIVE.
   1275     bool            MergeMode;                  // false    // Merge into previous ImFont, so you can combine multiple inputs font into one ImFont (e.g. ASCII font + icons + Japanese glyphs). You may want to use GlyphOffset.y when merge font of different heights.
   1276 
   1277     // [Internal]
   1278     char            Name[32];                               // Name (strictly for debugging)
   1279     ImFont*         DstFont;
   1280 
   1281     IMGUI_API ImFontConfig();
   1282 };
   1283 
   1284 // Load and rasterize multiple TTF fonts into a same texture.
   1285 // Sharing a texture for multiple fonts allows us to reduce the number of draw calls during rendering.
   1286 // We also add custom graphic data into the texture that serves for ImGui.
   1287 //  1. (Optional) Call AddFont*** functions. If you don't call any, the default font will be loaded for you.
   1288 //  2. Call GetTexDataAsAlpha8() or GetTexDataAsRGBA32() to build and retrieve pixels data.
   1289 //  3. Upload the pixels data into a texture within your graphics system.
   1290 //  4. Call SetTexID(my_tex_id); and pass the pointer/identifier to your texture. This value will be passed back to you during rendering to identify the texture.
   1291 //  5. Call ClearTexData() to free textures memory on the heap.
   1292 // NB: If you use a 'glyph_ranges' array you need to make sure that your array persist up until the ImFont is cleared. We only copy the pointer, not the data.
   1293 struct ImFontAtlas
   1294 {
   1295     IMGUI_API ImFontAtlas();
   1296     IMGUI_API ~ImFontAtlas();
   1297     IMGUI_API ImFont*           AddFont(const ImFontConfig* font_cfg);
   1298     IMGUI_API ImFont*           AddFontDefault(const ImFontConfig* font_cfg = NULL);
   1299     IMGUI_API ImFont*           AddFontFromFileTTF(const char* filename, float size_pixels, const ImFontConfig* font_cfg = NULL, const ImWchar* glyph_ranges = NULL);
   1300     IMGUI_API ImFont*           AddFontFromMemoryTTF(void* ttf_data, int ttf_size, float size_pixels, const ImFontConfig* font_cfg = NULL, const ImWchar* glyph_ranges = NULL);                                        // Transfer ownership of 'ttf_data' to ImFontAtlas, will be deleted after Build()
   1301     IMGUI_API ImFont*           AddFontFromMemoryCompressedTTF(const void* compressed_ttf_data, int compressed_ttf_size, float size_pixels, const ImFontConfig* font_cfg = NULL, const ImWchar* glyph_ranges = NULL);  // 'compressed_ttf_data' still owned by caller. Compress with binary_to_compressed_c.cpp
   1302     IMGUI_API ImFont*           AddFontFromMemoryCompressedBase85TTF(const char* compressed_ttf_data_base85, float size_pixels, const ImFontConfig* font_cfg = NULL, const ImWchar* glyph_ranges = NULL);              // 'compressed_ttf_data_base85' still owned by caller. Compress with binary_to_compressed_c.cpp with -base85 paramaeter
   1303     IMGUI_API void              ClearTexData();             // Clear the CPU-side texture data. Saves RAM once the texture has been copied to graphics memory.
   1304     IMGUI_API void              ClearInputData();           // Clear the input TTF data (inc sizes, glyph ranges)
   1305     IMGUI_API void              ClearFonts();               // Clear the ImGui-side font data (glyphs storage, UV coordinates)
   1306     IMGUI_API void              Clear();                    // Clear all
   1307 
   1308     // Retrieve texture data
   1309     // User is in charge of copying the pixels into graphics memory, then call SetTextureUserID()
   1310     // After loading the texture into your graphic system, store your texture handle in 'TexID' (ignore if you aren't using multiple fonts nor images)
   1311     // RGBA32 format is provided for convenience and high compatibility, but note that all RGB pixels are white, so 75% of the memory is wasted.
   1312     // Pitch = Width * BytesPerPixels
   1313     IMGUI_API void              GetTexDataAsAlpha8(unsigned char** out_pixels, int* out_width, int* out_height, int* out_bytes_per_pixel = NULL);  // 1 byte per-pixel
   1314     IMGUI_API void              GetTexDataAsRGBA32(unsigned char** out_pixels, int* out_width, int* out_height, int* out_bytes_per_pixel = NULL);  // 4 bytes-per-pixel
   1315     void                        SetTexID(ImTextureID id)  { TexID = id; }
   1316 
   1317     // Helpers to retrieve list of common Unicode ranges (2 value per range, values are inclusive, zero-terminated list)
   1318     // NB: Make sure that your string are UTF-8 and NOT in your local code page. See FAQ for details.
   1319     IMGUI_API const ImWchar*    GetGlyphRangesDefault();    // Basic Latin, Extended Latin
   1320     IMGUI_API const ImWchar*    GetGlyphRangesKorean();     // Default + Korean characters
   1321     IMGUI_API const ImWchar*    GetGlyphRangesJapanese();   // Default + Hiragana, Katakana, Half-Width, Selection of 1946 Ideographs
   1322     IMGUI_API const ImWchar*    GetGlyphRangesChinese();    // Japanese + full set of about 21000 CJK Unified Ideographs
   1323     IMGUI_API const ImWchar*    GetGlyphRangesCyrillic();   // Default + about 400 Cyrillic characters
   1324     IMGUI_API const ImWchar*    GetGlyphRangesThai();       // Default + Thai characters
   1325 
   1326     // Members
   1327     // (Access texture data via GetTexData*() calls which will setup a default font for you.)
   1328     ImTextureID                 TexID;              // User data to refer to the texture once it has been uploaded to user's graphic systems. It is passed back to you during rendering via the ImDrawCmd structure.
   1329     unsigned char*              TexPixelsAlpha8;    // 1 component per pixel, each component is unsigned 8-bit. Total size = TexWidth * TexHeight
   1330     unsigned int*               TexPixelsRGBA32;    // 4 component per pixel, each component is unsigned 8-bit. Total size = TexWidth * TexHeight * 4
   1331     int                         TexWidth;           // Texture width calculated during Build().
   1332     int                         TexHeight;          // Texture height calculated during Build().
   1333     int                         TexDesiredWidth;    // Texture width desired by user before Build(). Must be a power-of-two. If have many glyphs your graphics API have texture size restrictions you may want to increase texture width to decrease height.
   1334     ImVec2                      TexUvWhitePixel;    // Texture coordinates to a white pixel
   1335     ImVector<ImFont*>           Fonts;              // Hold all the fonts returned by AddFont*. Fonts[0] is the default font upon calling ImGui::NewFrame(), use ImGui::PushFont()/PopFont() to change the current font.
   1336 
   1337     // Private
   1338     ImVector<ImFontConfig>      ConfigData;         // Internal data
   1339     IMGUI_API bool              Build();            // Build pixels data. This is automatically for you by the GetTexData*** functions.
   1340     IMGUI_API void              RenderCustomTexData(int pass, void* rects);
   1341 };
   1342 
   1343 // Font runtime data and rendering
   1344 // ImFontAtlas automatically loads a default embedded font for you when you call GetTexDataAsAlpha8() or GetTexDataAsRGBA32().
   1345 struct ImFont
   1346 {
   1347     struct Glyph
   1348     {
   1349         ImWchar                 Codepoint;
   1350         float                   XAdvance;
   1351         float                   X0, Y0, X1, Y1;
   1352         float                   U0, V0, U1, V1;     // Texture coordinates
   1353     };
   1354 
   1355     // Members: Hot ~62/78 bytes
   1356     float                       FontSize;           // <user set>   // Height of characters, set during loading (don't change after loading)
   1357     float                       Scale;              // = 1.f        // Base font scale, multiplied by the per-window font scale which you can adjust with SetFontScale()
   1358     ImVec2                      DisplayOffset;      // = (0.f,1.f)  // Offset font rendering by xx pixels
   1359     ImVector<Glyph>             Glyphs;             //              // All glyphs.
   1360     ImVector<float>             IndexXAdvance;      //              // Sparse. Glyphs->XAdvance in a directly indexable way (more cache-friendly, for CalcTextSize functions which are often bottleneck in large UI).
   1361     ImVector<unsigned short>    IndexLookup;        //              // Sparse. Index glyphs by Unicode code-point.
   1362     const Glyph*                FallbackGlyph;      // == FindGlyph(FontFallbackChar)
   1363     float                       FallbackXAdvance;   // == FallbackGlyph->XAdvance
   1364     ImWchar                     FallbackChar;       // = '?'        // Replacement glyph if one isn't found. Only set via SetFallbackChar()
   1365 
   1366     // Members: Cold ~18/26 bytes
   1367     short                       ConfigDataCount;    // ~ 1          // Number of ImFontConfig involved in creating this font. Bigger than 1 when merging multiple font sources into one ImFont.
   1368     ImFontConfig*               ConfigData;         //              // Pointer within ContainerAtlas->ConfigData
   1369     ImFontAtlas*                ContainerAtlas;     //              // What we has been loaded into
   1370     float                       Ascent, Descent;    //              // Ascent: distance from top to bottom of e.g. 'A' [0..FontSize]
   1371     int                         MetricsTotalSurface;//              // Total surface in pixels to get an idea of the font rasterization/texture cost (not exact, we approximate the cost of padding between glyphs)
   1372 
   1373     // Methods
   1374     IMGUI_API ImFont();
   1375     IMGUI_API ~ImFont();
   1376     IMGUI_API void              Clear();
   1377     IMGUI_API void              BuildLookupTable();
   1378     IMGUI_API const Glyph*      FindGlyph(ImWchar c) const;
   1379     IMGUI_API void              SetFallbackChar(ImWchar c);
   1380     float                       GetCharAdvance(ImWchar c) const     { return ((int)c < IndexXAdvance.Size) ? IndexXAdvance[(int)c] : FallbackXAdvance; }
   1381     bool                        IsLoaded() const                    { return ContainerAtlas != NULL; }
   1382 
   1383     // 'max_width' stops rendering after a certain width (could be turned into a 2d size). FLT_MAX to disable.
   1384     // 'wrap_width' enable automatic word-wrapping across multiple lines to fit into given width. 0.0f to disable.
   1385     IMGUI_API ImVec2            CalcTextSizeA(float size, float max_width, float wrap_width, const char* text_begin, const char* text_end = NULL, const char** remaining = NULL) const; // utf8
   1386     IMGUI_API const char*       CalcWordWrapPositionA(float scale, const char* text, const char* text_end, float wrap_width) const;
   1387     IMGUI_API void              RenderChar(ImDrawList* draw_list, float size, ImVec2 pos, ImU32 col, unsigned short c) const;
   1388     IMGUI_API void              RenderText(ImDrawList* draw_list, float size, ImVec2 pos, ImU32 col, const ImVec4& clip_rect, const char* text_begin, const char* text_end, float wrap_width = 0.0f, bool cpu_fine_clip = false) const;
   1389 
   1390     // Private
   1391     IMGUI_API void              GrowIndex(int new_size);
   1392     IMGUI_API void              AddRemapChar(ImWchar dst, ImWchar src, bool overwrite_dst = true); // Makes 'dst' character/glyph points to 'src' character/glyph. Currently needs to be called AFTER fonts have been built.
   1393 };
   1394 
   1395 #if defined(__clang__)
   1396 #pragma clang diagnostic pop
   1397 #endif
   1398 
   1399 // Include imgui_user.h at the end of imgui.h (convenient for user to only explicitly include vanilla imgui.h)
   1400 #ifdef IMGUI_INCLUDE_IMGUI_USER_H
   1401 #include "imgui_user.h"
   1402 #endif