medfall

commit 76e4d4bd0c357d4ffe37ae615a8f2c5d03d55c89
parent 9a6e5b2439b28d5a0d5c18349704968660f2b3f3
Author: Michael Savage <mikejsavage@gmail.com>
Date:   Tue Aug 18 20:39:50 +0200

Make the immediate API colourful

Diffstat:
hm.cc
 | 
23
+++++++++++++++++------
immediate.cc
 | 
31
++++++++++++++++++++++---------
immediate.h
 | 
13
++++++++-----
3 files changed, 47 insertions(+), 20 deletions(-)
diff --git a/hm.cc b/hm.cc
@@ -21,17 +21,23 @@
 
 static const GLchar * const vert_src = GLSL(
 	in vec3 position;
+	in vec3 colour;
+
+	out vec3 frag_colour;
 
 	void main() {
 		gl_Position = 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( 1.0, 0.0, 0.0, 1.0 );
+		screen_colour = vec4( frag_colour, 1.0 );
 	}
 );
 
@@ -74,6 +80,7 @@ extern "C" GAME_INIT( game_init ) {
 
 	state->test_shader = compile_shader( vert_src, frag_src, "screen_colour" );
 	state->test_at_position = glGetAttribLocation( state->test_shader, "position" );
+	state->test_at_colour = glGetAttribLocation( state->test_shader, "colour" );
 
 	// TODO: persistent memory should be an arena
 	const size_t triangles = 65536;
@@ -87,22 +94,26 @@ extern "C" GAME_INIT( game_init ) {
 	immediate_triangle( &state->test_immediate,
 		glm::vec3( -crosshair_length, -crosshair_thickness, 0 ),
 		glm::vec3( -crosshair_length,  crosshair_thickness, 0 ),
-		glm::vec3(  crosshair_length,  crosshair_thickness, 0 )
+		glm::vec3(  crosshair_length,  crosshair_thickness, 0 ),
+		glm::vec3( 1, 0, 0 )
 	);
 	immediate_triangle( &state->test_immediate,
 		glm::vec3(  crosshair_length,  crosshair_thickness, 0 ),
 		glm::vec3(  crosshair_length, -crosshair_thickness, 0 ),
-		glm::vec3( -crosshair_length, -crosshair_thickness, 0 )
+		glm::vec3( -crosshair_length, -crosshair_thickness, 0 ),
+		glm::vec3( 1, 0, 0 )
 	);
 	immediate_triangle( &state->test_immediate,
 		glm::vec3( -crosshair_thickness / aspect,  crosshair_length * aspect , 0 ),
 		glm::vec3(  crosshair_thickness / aspect,  crosshair_length * aspect , 0 ),
-		glm::vec3(  crosshair_thickness / aspect, -crosshair_length * aspect , 0 )
+		glm::vec3(  crosshair_thickness / aspect, -crosshair_length * aspect , 0 ),
+		glm::vec3( 1, 0, 0 )
 	);
 	immediate_triangle( &state->test_immediate,
 		glm::vec3(  crosshair_thickness / aspect, -crosshair_length * aspect , 0 ),
 		glm::vec3( -crosshair_thickness / aspect, -crosshair_length * aspect , 0 ),
-		glm::vec3( -crosshair_thickness / aspect,  crosshair_length * aspect , 0 )
+		glm::vec3( -crosshair_thickness / aspect,  crosshair_length * aspect , 0 ),
+		glm::vec3( 1, 0, 0 )
 	);
 
 	glClearColor( 0, 0.5, 0.7, 1 );
@@ -148,6 +159,6 @@ extern "C" GAME_FRAME( game_frame ) {
 
 	glDisable( GL_DEPTH_TEST );
 	glUseProgram( state->test_shader );
-	immediate_render( &state->test_immediate, state->test_at_position );
+	immediate_render( &state->test_immediate, state->test_at_position, state->test_at_colour );
 	glEnable( GL_DEPTH_TEST );
 }
diff --git a/immediate.cc b/immediate.cc
@@ -10,25 +10,38 @@ void immediate_init( ImmediateContext * const ctx, ImmediateTriangle * const mem
 	ctx->max_triangles = max_triangles;
 }
 
-void immediate_triangle( ImmediateContext * const ctx, const glm::vec3 v1, const glm::vec3 v2, const glm::vec3 v3 ) {
+void immediate_triangle( ImmediateContext * const ctx,
+	const glm::vec3 v1, const glm::vec3 v2, const glm::vec3 v3,
+	const glm::vec3 colour
+) {
 	assert( ctx->num_triangles < ctx->max_triangles - 1 );
 
-	ctx->triangles[ ctx->num_triangles++ ] = { v1, v2, v3 };
+	const ImmediateTriangle triangle = { {
+		{ v1, colour },
+		{ v2, colour },
+		{ v3, colour },
+	} };
+
+	ctx->triangles[ ctx->num_triangles++ ] = triangle;
 }
 
-void immediate_render( ImmediateContext * const ctx, const GLuint at_position ) {
-	GLuint vbo;
-	glGenBuffers( 1, &vbo );
+void immediate_render( ImmediateContext * const ctx, const GLuint at_position, const GLuint at_colour ) {
+	GLuint vbos[ 2 ];
+	glGenBuffers( 2, vbos );
 
-	glBindBuffer( GL_ARRAY_BUFFER, vbo );
+	glBindBuffer( GL_ARRAY_BUFFER, vbos[ 0 ] );
 	glBufferData( GL_ARRAY_BUFFER, ctx->num_triangles * sizeof( ImmediateTriangle ), ctx->triangles, GL_STATIC_DRAW );
-
 	glEnableVertexAttribArray( at_position );
-	glVertexAttribPointer( at_position, 3, GL_FLOAT, GL_FALSE, 0, 0 );
+	glVertexAttribPointer( at_position, 3, GL_FLOAT, GL_FALSE, sizeof( ImmediateVertex ), 0 );
+
+	glBindBuffer( GL_ARRAY_BUFFER, vbos[ 1 ] );
+	glBufferData( GL_ARRAY_BUFFER, ctx->num_triangles * sizeof( ImmediateTriangle ), ctx->triangles, GL_STATIC_DRAW );
+	glEnableVertexAttribArray( at_colour );
+	glVertexAttribPointer( at_colour, 3, GL_FLOAT, GL_FALSE, sizeof( ImmediateVertex ), ( GLvoid * ) sizeof( glm::vec3 ) );
 
 	glDrawArrays( GL_TRIANGLES, 0, ctx->num_triangles * 3 );
 
-	glDeleteBuffers( 1, &vbo );
+	glDeleteBuffers( 2, vbos );
 }
 
 void immediate_clear( ImmediateContext * const ctx ) {
diff --git a/immediate.h b/immediate.h
@@ -3,10 +3,13 @@
 
 #include <glm/glm.hpp>
 
+struct ImmediateVertex {
+	glm::vec3 pos;
+	glm::vec3 colour;
+};
+
 struct ImmediateTriangle {
-	glm::vec3 v1;
-	glm::vec3 v2;
-	glm::vec3 v3;
+	ImmediateVertex vertices[ 3 ];
 };
 
 struct ImmediateContext {
@@ -16,8 +19,8 @@ struct ImmediateContext {
 };
 
 void immediate_init( ImmediateContext * const ctx, ImmediateTriangle * const memory, const size_t max_triangles );
-void immediate_triangle( ImmediateContext * const ctx, const glm::vec3 v1, const glm::vec3 v2, const glm::vec3 v3 );
-void immediate_render( ImmediateContext * const ctx, const GLuint at_position );
+void immediate_triangle( ImmediateContext * const ctx, const glm::vec3 v1, const glm::vec3 v2, const glm::vec3 v3, const glm::vec3 colour );
+void immediate_render( ImmediateContext * const ctx, const GLuint at_position, const GLuint at_colour );
 void immediate_clear( ImmediateContext * const ctx );
 
 #endif // _IMMEDIATE_H_