use new initGLBackingBuffer helper for lights and transform UBOs

include/shader.h

@@ -5,6 +5,7 @@
 #include <GL/glew.h>
 #include <glm/glm.hpp>
 
+#include "asset.h"
 #include "types.h"
 #include "util.h"
 
@@ -219,11 +220,3 @@ GLMesh loadGLMesh(MemoryArena* arena,
 	u32 num_mappings,
 	GLBufferToAttribMapping mappings[]);
 
-void initTransforms(MemoryArena* arena,
-	Transforms* xforms,
-	GLBuffer* xform_ubo,
-	GLContext* gl_ctx,
-	float fov = DEFAULT_FOV,
-	float near_clip_plane = NEAR_CLIP_PLANE,
-	float aspect_ratio = DEFAULT_ASPECT_RATIO);
-

src/shader.cpp

@@ -281,34 +281,6 @@ renderVAO(GLMesh* glmesh,
 	glBindVertexArray(0);
 }
 
-void
-initTransforms(MemoryArena* arena,
-	Transforms* xforms,
-	GLBuffer* xform_ubo,
-	GLContext* gl_ctx,
-	float fov,
-	float near_clip_plane,
-	float aspect_ratio)
-{
-	xforms->proj_xform = glm::infinitePerspective(
-		glm::radians(fov), aspect_ratio, near_clip_plane);
-
-	glGenBuffers(1, &xform_ubo->id);
-	xform_ubo->target = GL_UNIFORM_BUFFER;
-	xform_ubo->data_type = GL_FLOAT;
-	xform_ubo->name = arenaCopyCStr(arena, "matrices");
-	xform_ubo->data_size = sizeof(*xforms);
-
-	glBindBuffer(xform_ubo->target, xform_ubo->id);
-	glBufferData(xform_ubo->target, xform_ubo->data_size, xforms,
-				GL_DYNAMIC_DRAW);
-
-	// NOTE: bindbufferbase
-	xform_ubo->binding_idx = gl_ctx->binding_count++;
-	glBindBufferBase(xform_ubo->target, xform_ubo->binding_idx, xform_ubo->id);
-	glBindBuffer(xform_ubo->target, 0);
-}
-
 GLVertexAttrib*
 getVertexAttribByName(ShaderProgram* shader, const char* name)
 {

src/tangerine.cpp

@@ -1,6 +1,8 @@
 
 #include <cassert>
 
+#include <glm/gtc/matrix_transform.hpp>
+
 #include "tangerine.h"
 #define UTIL_IMPLEMENTATION
 #include "util.h"
@@ -54,14 +56,20 @@ initRenderState(GLClearColor clear_col,
 				max_textures,
 				max_ubos);
 
-		rs->xforms = ARENA_ALLOC(rs->assets.arena, Transforms, 1);
-		GLBuffer* xforms_ubo = getFreeUBO(rs->gl_ctx);
+		rs->camera = UTIL_ALLOC(1, Camera);
+		GLBuffer* xforms_ubo = initGLBackingBuffer(rs->gl_ctx,
+													rs->assets.arena,
+													"matrices",
+													GL_FLOAT,
+													sizeof(Transforms),
+													&rs->camera->xforms);
 		assert(xforms_ubo);
-		initTransforms(rs->assets.arena, rs->xforms, xforms_ubo, rs->gl_ctx);
 
-		rs->lights_buf = initLights(rs->rg_arena, rs->gl_ctx, max_lights,
-									ambient_color);
+		// FIXME: should this be an interface function?
+		rs->lights_buf = initLights(rs, max_lights, ambient_color);
 
+		// FIXME: should have an error message instead of assert here, and
+		// 	clean up arenas/allocations before returning
 		bool ret = loadDefaultShaders(rs);
 		assert(ret);
 	}
@@ -313,19 +321,20 @@ initGraphics(SDLHandles* handles)
 }
 
 LightsBuffer*
-initLights(MemoryArena* arena,
-	GLContext* gl_ctx,
+initLights(RenderState* rs,
 	u32 max_lights,
 	glm::vec4 ambient_color)
 {
 	// FIXME: revisit for 'Scene' abstraction
+	// FIXME: see if we can simplify this with the use of offsetof()
+	// 	https://en.cppreference.com/w/cpp/types/offsetof
 
-	LightsBuffer* lb = ARENA_ALLOC(arena, LightsBuffer, 1);
+	LightsBuffer* lb = ARENA_ALLOC(rs->assets.arena, LightsBuffer, 1);
 	lb->buf_size = 8 * sizeof(u32) // NOTE: 'header'
 				+ sizeof(glm::vec4) // NOTE: ambient color
 				+ 6 * max_lights * sizeof(glm::vec4); // NOTE: vector arrays
 	LOGF(Debug, "buf_size: %d\n", lb->buf_size);
-	lb->buffer = ARENA_ALLOC(arena, u8, lb->buf_size);
+	lb->buffer = ARENA_ALLOC(rs->assets.arena, u8, lb->buf_size);
 
 	lb->max_p_lights = (u32*) lb->buffer;
 	lb->active_p_lights =
@@ -362,25 +371,12 @@ initLights(MemoryArena* arena,
 	lb->dl_intensities =
 		(glm::uvec4*) arenaGetAddressOffset(lb->dl_colors, arr_size);
 
-	GLBuffer* lights_ubo = getFreeUBO(gl_ctx);
-	assert(lights_ubo);
-
-	lights_ubo->target = GL_UNIFORM_BUFFER;
-	lights_ubo->data_type = GL_BYTE;	// NOTE: mixed types in structure
-	lights_ubo->data_size = lb->buf_size;
-	lights_ubo->name = arenaCopyCStr(arena, "lights");
-	assert((GLint) gl_ctx->binding_count < gl_ctx->max_binding_points);
-	lights_ubo->binding_idx = gl_ctx->binding_count++;
-
-	glGenBuffers(1, &lights_ubo->id);
-	glBindBuffer(lights_ubo->target, lights_ubo->id);
-	glBufferData(lights_ubo->target,
+	initGLBackingBuffer(rs->gl_ctx,
+						rs->assets.arena,
+						"lights",
+						GL_BYTE,
 						lb->buf_size,
-				lb->buffer,
-				GL_DYNAMIC_DRAW);
-	glBindBufferBase(lights_ubo->target,
-					lights_ubo->binding_idx,
-					lights_ubo->id);
+						lb->buffer);
 
 	return lb;
 }