Implemented immediate mode renderer for debug drawing and drawing arbitrary points, lines and triangles

README.md

@@ -156,6 +156,7 @@
 - ## TODO
 
 	- Physics forces/torque etc
+	- Replace all renderer_check_gl calls with GL_CHECK macro
 	- Fix lights type not being correctly saved/loaded from file
 	- Physics Trimesh support
 	- Debug physics mesh drawing
@@ -365,3 +366,4 @@
 	* Implemented Getting/Modifying primitive physics shapes' values like length, radius etc
 	* Update physics if entity position/rotation/scale etc are changed
 	* Implemented Physics raycasting
+	* Implemented immediate mode renderer that can draw arbitrary points, lines and triangles

assets/shaders/im_geom.frag

@@ -0,0 +1,10 @@
+//include version.glsl
+
+in vec4 color;
+
+out vec4 frag_color;
+
+void main()
+{
+	frag_color = color;
+}

assets/shaders/im_geom.vert

@@ -0,0 +1,14 @@
+//include version.glsl
+
+uniform mat4 mvp;
+
+in vec3 vPosition;
+in vec4 vColor;
+
+out vec4 color;
+
+void main()
+{
+	gl_Position = mvp * vec4(vPosition, 1.0);
+	color = vColor;
+}

src/libsymmetry/game.c

@@ -30,6 +30,7 @@
 #include "../common/hashmap.h"
 #include "../common/variant.h"
 #include "../common/common.h"
+#include "im_render.h"
 
 #define UNUSED(a) (void)a
 #ifndef _MSC_VER
@@ -450,6 +451,76 @@ void debug(float dt)
 		}
 		platform->physics.cs_remove(ray);
 	}
+
+	// Immediate geometry test
+	vec3 im_position = { 0.f, 20.f, 0.f };
+	vec3 im_scale    = { 1.f, 1.f, 1.f };
+	quat im_rot      = { 0.f, 0.f, 0.f, 1.f };
+	quat_identity(&im_rot);
+	im_begin(im_position, im_rot, im_scale, GL_LINES);
+
+	im_color(0.f, 1.f, 0.f, 1.f);
+	im_pos(0.f, 0.f, 0.f);
+	im_pos(100.f, 100.f, 10.f);
+
+	im_end();
+
+	im_position.x = -10;
+	im_begin(im_position, im_rot, im_scale, GL_TRIANGLES);
+
+	//Front
+	im_pos(0.f,  0.f,  0.f);
+	im_pos(0.f,  20.f, 0.f);
+	im_pos(20.f, 20.f, 0.f);
+	im_pos(20.f, 20.f, 0.f);
+	im_pos(20.f,  0.f, 0.f);
+	im_pos( 0.f,  0.f, 0.f);
+
+	//Back
+	im_pos(0.f,  0.f,  20.f);
+	im_pos(0.f,  20.f, 20.f);
+	im_pos(20.f, 20.f, 20.f);
+	im_pos(20.f, 20.f, 20.f);
+	im_pos(20.f,  0.f, 20.f);
+	im_pos( 0.f,  0.f, 20.f);
+
+	//Left
+	im_pos(0.f,  0.f,  0.f);
+	im_pos(0.f,  0.f, 20.f);
+	im_pos(0.f,  20.f, 20.f);
+	im_pos(0.f,  20.f, 20.f);
+	im_pos(0.f, 20.f, 0.f);
+	im_pos(0.f,  0.f, 20.f);
+
+	//Right
+	im_pos(20.f,  0.f,  0.f);
+	im_pos(20.f,  0.f, 20.f);
+	im_pos(20.f,  20.f, 20.f);
+	im_pos(20.f,  20.f, 20.f);
+	im_pos(20.f, 20.f, 0.f);
+	im_pos(20.f,  0.f, 20.f);
+
+	im_end();
+
+	im_position.x = -30.f;
+	im_begin(im_position, im_rot, im_scale, GL_LINES);
+	im_color(1.f, 1.f, 0.f, 1.f);
+
+	im_pos(0.f, 0.f, 0.f);
+	im_pos(0.f, 0.f, 10.f);
+
+	im_pos(0.f, 0.f, 10.f);
+	im_pos(0.f, 10.f, 10.f);
+
+	im_pos(0.f, 10.f, 10.f);
+	im_pos(0.f, 10.f, 0.f);
+
+	im_pos(0.f, 10.f, 0.f);
+	im_pos(0.f, 0.f, 0.f);
+
+	im_end();
+
+	
 }
 
 bool run(void)

src/libsymmetry/gl_load.c

@@ -44,4 +44,27 @@ bool gl_load_extentions(void)
 #undef GLE
 #endif
 	return success;
-}
+}
+
+void gl_check_error(const char * expression, unsigned int line, const char * file)
+{
+	int error = 1;
+	GLenum error_code = glGetError();
+	const char* error_string = "No Error";
+	switch(error_code)
+	{
+	case GL_INVALID_OPERATION: 			   error_string = "Invalid Operation"; 		       break;
+	case GL_NO_ERROR:		   			   error_string = "No Error";		  		       break;
+	case GL_INVALID_ENUM:	   			   error_string = "Invalid ENUM";	  		       break;
+	case GL_INVALID_VALUE:	   			   error_string = "Invalid Value";	  		       break;
+	case GL_INVALID_FRAMEBUFFER_OPERATION: error_string = "Invalid FrameBuffer Operation"; break;
+	case GL_OUT_OF_MEMORY:		           error_string = "Out of Memory";		           break;
+	}
+
+	if(error_code != GL_NO_ERROR)
+		log_error("GL", "(%s:%d:%s) : %s", file, line, expression, error_string);
+	else
+		error = 0;
+
+	return error;
+}

src/libsymmetry/gl_load.h

@@ -61,8 +61,17 @@ SYMMETRY_GL_LIST
 
 #endif
 
+
+#ifdef GL_DEBUG
+	#define GL_CHECK(expression) do { gl_check(#expression, __LINE__, __FILE__)} while(false)
+#else
+	#define GL_CHECK(expression) (expression)
+
+#endif
+
 int  gl_load_library(void);
 bool gl_load_extentions(void);
+void gl_check_error(const char* expression, unsigned int line, const char* file);
 void gl_cleanup(void);
 
 #endif

src/libsymmetry/im_render.c

@@ -0,0 +1,157 @@
+#include "im_render.h"
+#include "entity.h"
+#include "camera.h"
+#include "gl_load.h"
+#include "../common/array.h"
+#include "../common/num_types.h"
+#include "shader.h"
+#include "../common/log.h"
+
+#define MAX_IM_VERTICES 4096
+#define MAX_IM_GEOMETRIES (MAX_IM_VERTICES / 2)
+
+static struct
+{
+	struct IM_Vertex vertices[MAX_IM_VERTICES];
+	struct IM_Geom   geometries[MAX_IM_GEOMETRIES];
+	uint             vao;
+	uint             vbo;
+	int              im_shader;
+	int              curr_geom;
+	int              curr_vertex;
+	vec4             default_color;
+}
+IM_State;
+
+static struct IM_Geom* active_geom = NULL;
+static vec4 active_vertex_color  = { 0.f, 0.f, 0.f, 0.f };
+
+void im_init(void)
+{
+	glGenVertexArrays(1, &IM_State.vao);
+	glBindVertexArray(IM_State.vao);
+
+	glGenBuffers(1, &IM_State.vbo);
+	glBindBuffer(GL_ARRAY_BUFFER, IM_State.vbo);
+	GL_CHECK(glBufferData(GL_ARRAY_BUFFER, sizeof(struct IM_Vertex) * MAX_IM_VERTICES, NULL, GL_STREAM_DRAW));
+
+	//Position
+	GL_CHECK(glVertexAttribPointer(ATTRIB_LOC_POSITION, 3, GL_FLOAT, GL_FALSE, sizeof(struct IM_Vertex), 0));
+	GL_CHECK(glEnableVertexAttribArray(ATTRIB_LOC_POSITION));
+
+	//Color
+	GL_CHECK(glVertexAttribPointer(ATTRIB_LOC_COLOR, 4, GL_FLOAT, GL_FALSE, sizeof(struct IM_Vertex), sizeof(vec3)));
+	GL_CHECK(glEnableVertexAttribArray(ATTRIB_LOC_COLOR));
+
+	glBindBuffer(GL_ARRAY_BUFFER, 0);
+
+	glBindVertexArray(0);
+
+	memset(&IM_State.geometries[0], 0, sizeof(struct IM_Geom) * MAX_IM_GEOMETRIES);
+	memset(&IM_State.vertices[0], 0, sizeof(struct IM_Vertex) * MAX_IM_VERTICES);
+	IM_State.curr_geom   = -1;
+	IM_State.curr_vertex =  0;
+	vec4_fill(&IM_State.default_color, 1.f, 0.f, 1.f, 1.f);
+	vec4_assign(&active_vertex_color, &IM_State.default_color);
+
+	IM_State.im_shader = shader_create("im_geom.vert", "im_geom.frag");
+}
+
+void im_cleanup(void)
+{
+	shader_remove(IM_State.im_shader);
+	glDeleteBuffers(1, &IM_State.vbo);
+	glDeleteVertexArrays(1, &IM_State.vao);
+
+	memset(&IM_State.geometries[0], 0, sizeof(struct IM_Geom) * MAX_IM_GEOMETRIES);
+	memset(&IM_State.vertices[0], 0, sizeof(struct IM_Vertex) * MAX_IM_VERTICES);
+	IM_State.vao         =  0;
+	IM_State.vbo         =  0;
+	IM_State.curr_geom   = -1;
+	IM_State.curr_vertex =  0;
+	IM_State.im_shader   = -1;
+}
+
+void im_begin(vec3 position, quat rotation, vec3 scale, int draw_mode)
+{
+	if(active_geom)
+	{
+		log_error("im_begin", "im_begin called before im_end");
+		return;
+	}
+	IM_State.curr_geom++;
+	active_geom = &IM_State.geometries[IM_State.curr_geom];
+	active_geom->start_index = IM_State.curr_vertex;
+	active_geom->draw_mode = draw_mode;
+	vec3_assign(&active_geom->position, &position);
+	vec3_assign(&active_geom->scale, &scale);
+	quat_assign(&active_geom->rotation, &rotation);
+}
+
+void im_pos(float x, float y, float z)
+{
+	vec3_fill(&IM_State.vertices[IM_State.curr_vertex].position, x, y, z);
+	vec4_assign(&IM_State.vertices[IM_State.curr_vertex].color, &active_vertex_color);
+	IM_State.curr_vertex++;
+}
+
+void im_color(float r, float g, float b, float a)
+{
+	vec4_fill(&active_vertex_color, r, g, b, a);
+}
+
+void im_end(void)
+{
+	active_geom->num_vertices = IM_State.curr_vertex - active_geom->start_index;
+	glBindBuffer(GL_ARRAY_BUFFER, IM_State.vbo);
+	glBufferSubData(GL_ARRAY_BUFFER,
+					sizeof(struct IM_Vertex) * active_geom->start_index,
+					sizeof(struct IM_Vertex) * active_geom->num_vertices,
+					&IM_State.vertices[active_geom->start_index]);
+	renderer_check_glerror("sprite_batch_end:glBufferSubData");
+	glBindBuffer(GL_ARRAY_BUFFER, 0);
+	active_geom = NULL;
+	vec4_assign(&active_vertex_color, &IM_State.default_color);
+}
+
+void im_render(struct Entity* active_viewer)
+{
+	if(IM_State.curr_geom == -1)
+		return;
+
+	shader_bind(IM_State.im_shader);
+	{
+		static mat4 mvp, translation, rotation, scale;
+
+		glBindVertexArray(IM_State.vao);
+		for(int i = 0; i <= IM_State.curr_geom; i++)
+		{
+			struct IM_Geom* geom = &IM_State.geometries[i];
+			mat4_identity(&mvp);
+			
+			mat4_identity(&scale);
+			mat4_identity(&translation);
+			mat4_identity(&rotation);
+
+			mat4_scale(&scale, geom->scale.x, geom->scale.y, geom->scale.z);
+			mat4_translate(&translation, geom->position.x, geom->position.y, geom->position.z);
+			mat4_from_quat(&rotation, &geom->rotation);
+
+			mat4_mul(&mvp, &mvp, &translation);
+			mat4_mul(&mvp, &mvp, &rotation);
+			mat4_mul(&mvp, &mvp, &scale);
+
+			mat4_mul(&mvp, &active_viewer->camera.view_proj_mat, &mvp);
+
+			shader_set_uniform_mat4(IM_State.im_shader, "mvp", &mvp);
+
+			glDrawArrays(geom->draw_mode, geom->start_index, geom->num_vertices);
+		}
+		glBindVertexArray(0);
+
+	}
+	shader_unbind();
+
+	IM_State.curr_geom   = -1;
+	IM_State.curr_vertex =  0;
+}

src/libsymmetry/im_render.h

@@ -0,0 +1,32 @@
+#ifndef IM_RENDER_H
+#define IM_RENDER_H
+
+#include "../common/linmath.h"
+
+struct IM_Vertex
+{
+	vec3 position;
+	vec4 color;
+};
+
+struct IM_Geom
+{
+	vec3 position;
+	quat rotation;
+	vec3 scale;
+	int  start_index;
+	int  num_vertices;
+	int  draw_mode;
+};
+
+struct Entity;
+
+void im_init(void);
+void im_cleanup(void);
+void im_begin(vec3 position, quat rotation, vec3 scale, int draw_mode);
+void im_pos(float x, float y, float z);
+void im_color(float r, float g, float b, float a); // set active color
+void im_end(void);
+void im_render(struct Entity* active_viewer);
+
+#endif

src/libsymmetry/renderer.c

@@ -19,6 +19,7 @@
 #include "material.h"
 #include "editor.h"
 #include "sprite.h"
+#include "im_render.h"
 #include "../common/variant.h"
 #include "../common/common.h"
 
@@ -131,6 +132,8 @@ void renderer_init(void)
 	{
 		sprite_batch_create(sprite_batch, "sprite_map.tga", "sprite.vert", "sprite.frag", GL_TRIANGLES);
 	}
+
+	im_init();
 }
 
 void renderer_draw(struct Entity* active_viewer)
@@ -405,7 +408,9 @@ void renderer_draw(struct Entity* active_viewer)
 		glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
 	}
 
-	shader_unbind();
+	//Immediate mode geometry render
+	im_render(active_viewer);
+
 
 	/* Render 2D stuff */
 	shader_bind(sprite_batch->shader);
@@ -416,7 +421,7 @@ void renderer_draw(struct Entity* active_viewer)
 		struct Game_State* game_state = game_state_get();
 		platform->window.get_size(game_state->window, &width, &height);
 
-		mat4_ortho(&ortho_mat, 0, width, height, 0, -10.f, 10.f);
+		mat4_ortho(&ortho_mat, 0.f, (float)width, (float)height, 0.f, -10.f, 10.f);
 		shader_set_uniform_mat4(sprite_batch->shader, "mvp", &ortho_mat);
 
 		sprite_batch_render(sprite_batch);
@@ -429,6 +434,7 @@ void renderer_draw(struct Entity* active_viewer)
 
 void renderer_cleanup(void)
 {
+	im_cleanup();
 	sprite_batch_remove(sprite_batch);
 	free(sprite_batch);
 	gui_cleanup();
@@ -480,15 +486,11 @@ int renderer_check_glerror(const char* context)
 		error = 0;
 
 	return error;
-}
+}
-
+
-void im_render_box(float position, float length, float width, float height)
+struct Sprite_Batch * get_batch(void)
-{
+{
-}
+	return sprite_batch;
-
-struct Sprite_Batch * get_batch(void)
-{
-	return sprite_batch;
 }
 
 void renderer_debug_draw_enabled(bool enabled)

src/libsymmetry/renderer.h

@@ -43,8 +43,6 @@ void renderer_clearcolor_set(float r, float g, float b, float a);
 void renderer_debug_draw_enabled(bool enabled);
 int  renderer_check_glerror(const char* context);
 
-void im_render_box(float position, float length, float width, float height);
-
 struct Sprite_Batch* get_batch(void);
 
 #endif