medfall

commit 5ee37304fa4260a4ba6319f9a2f63b25ad5b4a35
parent 5cf6f34a70e3297c9eed22ac6291559b8e4a0244
Author: Michael Savage <mikejsavage@gmail.com>
Date:   Sun Jan 31 11:27:01 +0000

Add shadow_map.cc so sm.so builds

Diffstat:
shadow_map.cc
 | 
150
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 150 insertions(+), 0 deletions(-)
diff --git a/shadow_map.cc b/shadow_map.cc
@@ -0,0 +1,150 @@
+#include "platform_opengl.h"
+#include <glm/glm.hpp>
+#include <glm/gtc/matrix_transform.hpp>
+#include <glm/gtc/type_ptr.hpp>
+
+#include "game.h"
+#include "intrinsics.h"
+
+static ImmediateTriangle triangles[ 512000 ];
+static ImmediateContext imm;
+
+static GLuint prog;
+static GLint at_position;
+static GLint at_colour;
+static GLint un_vp;
+
+static GLuint fbo;
+static GLuint tex_depth;
+
+static const GLchar * const vert_src = GLSL(
+	in vec3 position;
+	in vec3 colour;
+
+	out vec3 frag_colour;
+
+	uniform mat4 VP;
+
+	void main() {
+		gl_Position = VP * vec4( position, 1.0 );
+		frag_colour = colour;
+	}
+);
+
+static const GLchar * frag_src = GLSL(
+	in vec3 frag_colour;
+
+	out vec4 screen_colour;
+
+	void main() {
+		screen_colour = vec4( frag_colour, 1.0 );
+	}
+);
+
+static void draw_scene( GLint at_position, GLint at_colour ) {
+	immediate_init( &imm, triangles, array_count( triangles ) );
+
+	immediate_sphere( &imm, glm::vec3( 0, 0, 5 ), 3, glm::vec4( 1, 0, 0, 1 ) );
+	immediate_sphere( &imm, glm::vec3( -3, 7, 5 ), 2, glm::vec4( 0, 1, 0, 1 ) );
+
+	glm::vec3 tl( -15,  15, 0 );
+	glm::vec3 tr(  15,  15, 0 );
+	glm::vec3 bl( -15, -15, 0 );
+	glm::vec3 br(  15, -15, 0 );
+	immediate_triangle( &imm, tl, tr, bl, glm::vec4( 0.5, 0.5, 0.5, 1.0 ) );
+	immediate_triangle( &imm, bl, tr, br, glm::vec4( 0.5, 0.5, 0.5, 1.0 ) );
+
+	immediate_render( &imm, at_position, at_colour );
+}
+
+static glm::vec3 angles_to_vector( const glm::vec3 & angles ) {
+	return glm::vec3(
+		-sin( angles.y ) * sin( angles.x ),
+		-cos( angles.y ) * sin( angles.x ),
+		-cos( angles.x )
+	);
+}
+
+static void update_camera(
+	const GameInput * input, float dt,
+	glm::vec3 position, glm::vec3 angles,
+	glm::vec3 * out_position, glm::vec3 * out_angles
+) {
+	float speed = 6.0f;
+	float angular_speed = 2.0f;
+
+	float dx = ( float ) input->keys[ 'a' ] - ( float ) input->keys[ 'd' ];
+	float dy = ( float ) input->keys[ 'w' ] - ( float ) input->keys[ 's' ];
+	float dz = ( float ) input->keys[ KEY_SPACE ] - ( float ) input->keys[ KEY_LEFTSHIFT ];
+
+	glm::vec3 forward = angles_to_vector( angles );
+	glm::vec3 sideways = glm::vec3( -cosf( angles.y ), sinf( angles.y ), 0 );
+
+	*out_position = position
+		+ forward * dt * dy * speed
+		+ sideways * dt * dx * speed;
+	out_position->z += dt * dz * speed;
+
+	float pitch = ( float ) input->keys[ KEY_UPARROW ] - ( float ) input->keys[ KEY_DOWNARROW ];
+	float yaw = ( float ) input->keys[ KEY_RIGHTARROW ] - ( float ) input->keys[ KEY_LEFTARROW ];
+
+	*out_angles = angles + glm::vec3( dt * pitch * angular_speed, dt * yaw * angular_speed, 0 );
+}
+
+static void camera_to_vp( glm::vec3 position, glm::vec3 angles, glm::mat4 * out_vp ) {
+	const glm::mat4 P( glm::perspective( glm::radians( 120.0f ), ( float ) WIDTH / ( float ) HEIGHT, NEAR, 100.0f ) );
+
+	*out_vp = glm::translate(
+		glm::rotate(
+			glm::rotate(
+				P,
+				angles.x,
+				glm::vec3( 1, 0, 0 )
+			),
+			angles.y,
+			glm::vec3( 0, 0, 1 )
+		),
+		-position
+	);
+}
+
+extern "C" GAME_INIT( game_init ) {
+	prog = compile_shader( vert_src, frag_src, "screen_colour" );
+	at_position = glGetAttribLocation( prog, "position" );
+	at_colour = glGetAttribLocation( prog, "colour" );
+	un_vp = glGetUniformLocation( prog, "VP" );
+
+	glGenFramebuffers( 1, &fbo );
+	glBindFramebuffer( GL_DRAW_FRAMEBUFFER, fbo );
+	glGenTextures( 1, &tex_depth );
+	glBindTexture( GL_TEXTURE_2D, tex_depth );
+
+	glTexImage2D( GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT32F, WIDTH, HEIGHT, 0, GL_DEPTH_COMPONENT, GL_FLOAT, NULL );
+	glFramebufferTexture2D( GL_DRAW_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, tex_depth, 0 );
+
+	glBindFramebuffer( GL_DRAW_FRAMEBUFFER, 0 );
+
+	state->pos = glm::vec3( -10, -10, 5 );
+	state->angles = glm::radians( ( glm::vec3( -90, 45, 0 ) ) );
+}
+
+extern "C" GAME_FRAME( game_frame ) {
+	glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
+
+	update_camera( input, dt, state->pos, state->angles, &state->pos, &state->angles );
+	glm::mat4 vp;
+	camera_to_vp( state->pos, state->angles, &vp );
+
+	glUseProgram( prog );
+	glUniformMatrix4fv( un_vp, 1, GL_FALSE, glm::value_ptr( vp ) );
+
+	glBindFramebuffer( GL_DRAW_FRAMEBUFFER, fbo );
+	draw_scene( at_position, at_colour );
+	glBindFramebuffer( GL_DRAW_FRAMEBUFFER, 0 );
+
+	glBindFramebuffer( GL_READ_FRAMEBUFFER, fbo );
+	glBlitFramebuffer( 0, 0, WIDTH, HEIGHT, 0, 0, WIDTH, HEIGHT, GL_COLOR_BUFFER_BIT, GL_LINEAR );
+	glBindFramebuffer( GL_READ_FRAMEBUFFER, 0 );
+
+	glUseProgram( 0 );
+}