medfall

commit de1de161b0ec09ffb3f35c32abe165b03bafe3a0
parent df530cce6214ed1f47af331f5e1b0d29ac21c088
Author: Michael Savage <mikejsavage@gmail.com>
Date:   Fri Dec 30 21:38:49 +0200

Simplify camera code in the BSP renderer

Diffstat:
bsp.cc
 | 
48
++++++++++++++++++++++++------------------------
game.h
 | 
3
++-
linear_algebra.h
 | 
20
++++++++++++++++++++
3 files changed, 46 insertions(+), 25 deletions(-)
diff --git a/bsp.cc b/bsp.cc
@@ -7,6 +7,7 @@
 #include "renderer.h"
 #include "bsp.h"
 #include "bsp_renderer.h"
+#include "text_renderer.h"
 
 static ImmediateTriangle triangles[ 512000 ];
 static ImmediateContext imm;
@@ -299,14 +300,6 @@ BSP_Leaf & BSP::position_to_leaf( v3 pos ) const {
 	return leaves[ -( node_idx + 1 ) ];
 }
 
-static v3 angles_to_vector( v3 angles ) {
-	return v3(
-		-sin( angles.y ) * sin( angles.x ),
-		-cos( angles.y ) * sin( angles.x ),
-		-cos( angles.x )
-	);
-}
-
 static UB test_ub;
 static Shader texture_shader;
 
@@ -316,7 +309,8 @@ extern "C" GAME_INIT( game_init ) {
 	MemoryArena arena = memarena_push_arena( &mem->persistent_arena, megabytes( 10 ) );
 
 	game->pos = v3( 0, -100, 450 );
-	game->angles = radians( v3( -90, 135, 0 ) );
+	game->pitch = 0;
+	game->yaw = 0;
 
 	game->test_shader = renderer_new_shader( vert_src, frag_src );
 
@@ -334,10 +328,6 @@ extern "C" GAME_INIT( game_init ) {
 	test_ub = renderer_new_ub();
 }
 
-static m4 camera_to_view( v3 position, v3 angles ) {
-	return m4_translation( -position ) * m4_rotz( -angles.y ) * m4_rotx( -angles.x );
-}
-
 struct FSData {
 	m4 V;
 	m4 P;
@@ -345,23 +335,26 @@ struct FSData {
 
 extern "C" GAME_FRAME( game_frame ) {
 	const int fb = input->keys[ KEY_W ] - input->keys[ KEY_S ];
-	const int lr = input->keys[ KEY_A ] - input->keys[ KEY_D ];
+	const int lr = input->keys[ KEY_D ] - input->keys[ KEY_A ];
 	const int dz = input->keys[ KEY_SPACE ] - input->keys[ KEY_LEFTSHIFT ];
 
-	const int pitch = input->keys[ KEY_UPARROW ] - input->keys[ KEY_DOWNARROW ];
-	const int yaw = input->keys[ KEY_RIGHTARROW ] - input->keys[ KEY_LEFTARROW ];
+	const int dpitch = input->keys[ KEY_DOWNARROW ] - input->keys[ KEY_UPARROW ];
+	const int dyaw = input->keys[ KEY_LEFTARROW ] - input->keys[ KEY_RIGHTARROW ];
+
+	game->pitch += dpitch * dt * 50;
+	game->yaw += dyaw * dt * 50;
 
-	game->angles.x += pitch * dt * 2;
-	game->angles.y += yaw * dt * 2;
+	const v3 world_up = v3( 0, 0, 1 );
+	const v3 forward = v3_forward( game->pitch, game->yaw );
+	const v3 right = normalize( cross( forward, world_up ) );
+	const v3 up = normalize( cross( right, forward ) );
 
-	const v3 forward = angles_to_vector( game->angles );
-	game->pos += forward * 100.0f * dt * ( float ) fb;
-	const v3 sideways = v3( -cosf( game->angles.y ), sinf( game->angles.y ), 0 );
-	game->pos += sideways * 100.0f * dt * ( float ) lr;
-	game->pos.z += ( float ) dz * 100.0f * dt;
+	game->pos += forward * 100.0f * dt * fb;
+	game->pos += right * 100.0f * dt * lr;
+	game->pos.z += dz * 100.0f * dt;
 
 	m4 P = m4_perspective( VERTICAL_FOV, ( float ) WIDTH / ( float ) HEIGHT, NEAR_PLANE_DEPTH, FAR_PLANE_DEPTH );
-	m4 V = camera_to_view( game->pos, game->angles );
+	m4 V = m4_view( forward, right, up, game->pos );
 
 	FSData fsdata = { V, P };
 
@@ -396,4 +389,11 @@ extern "C" GAME_FRAME( game_frame ) {
 	immediate_render_state.ubs[ UB_VS_HOT ] = test_ub;
 	immediate_render( &imm, immediate_render_state );
 
+	char buf[ 256 ];
+	snprintf( buf, sizeof( buf ), "pos: (%.2f %.2f %.2f) pitch: %.2f yaw: %.2f forward: (%.2f %.2f %.2f) right: (%.2f %.2f %.2f) up: (%.2f %.2f %.2f)", game->pos.x, game->pos.y, game->pos.z, game->pitch, game->yaw,
+		forward.x, forward.y, forward.z,
+		right.x, right.y, right.z,
+		up.x, up.y, up.z
+		);
+	draw_text( buf, 2, 2, 16 );
 }
diff --git a/game.h b/game.h
@@ -29,7 +29,8 @@ struct GameState {
 	GameState() { }
 
 	v3 pos;
-	v3 angles;
+	float pitch, yaw;
+
 	TerrainManager tm;
 
 	BSP bsp;
diff --git a/linear_algebra.h b/linear_algebra.h
@@ -397,6 +397,16 @@ forceinline v3 normalize( v3 v ) {
 	return v / length( v );
 }
 
+forceinline v3 v3_forward( float pitch, float yaw ) {
+	pitch = deg_to_rad( pitch );
+	yaw = deg_to_rad( yaw );
+	return v3(
+		cosf( pitch ) * cosf( yaw ),
+		cosf( pitch ) * sinf( yaw ),
+		sinf( pitch )
+	);
+}
+
 /*
  * v3u32
  */
@@ -723,6 +733,16 @@ forceinline m4 operator-( const m4 & m ) {
 	return m4( -m.col0, -m.col1, -m.col2, -m.col3 );
 }
 
+forceinline m4 m4_view( const v3 & forward, const v3 & right, const v3 & up, const v3 & position ) {
+	m4 rotation(
+		right.x, right.y, right.z, 0,
+		up.x, up.y, up.z, 0,
+		-forward.x, -forward.y, -forward.z, 0,
+		0, 0, 0, 1
+	);
+	return rotation * m4_translation( -position );
+}
+
 /*
  * quat
  */