update TODO and clean up camera raycast functions

TODO.md

@@ -24,6 +24,7 @@
 		- move glUniform call to lights[i].position out of rgDraw, and into scene_loader init phase
 		- show debug mesh for light positions
 		- attenuate point lights in shader
+	- simplify render_object buffers into 2d array or vector, and use stride when pushing to GL
 - remove checks for colors, textures from render_group functions
 	- actually cannot remove checks for texture because some meshes aren't loaded properly
 	- maybe can cause loading mesh to fail when more than one mesh per file
@@ -49,6 +50,7 @@
 - use assimp material info in shaders for fancier lighting
 - add cpu performance counters in render loop
 	- hgUpdateUV buffer can probably be improved by adding selected hexes to a small cache structure
+	- can also try passing in small chunks with glBufferSubData instead of overwriting whole buffer
 - check for memory leaks w/ valgrind
 
 ## DONE:

src/camera.cpp

@@ -74,53 +74,34 @@ cameraUnproject(camera& cam, int x, int y, int vp_width, int vp_height)
 v3f
 cameraCreateRay(camera& cam, v2i vp_coords, v2i vp_dims)
 {
-#if 0
-	float x = 2.f * vp_coords.x / vp_dims.x - 1.f;
-	float y = 2.f * vp_coords.y / vp_dims.y - 1.f;
-	glm::vec4 ray_start_ndc = glm::vec4(x, y, -1.f, 1.f);
-	glm::vec4 ray_end_ndc = glm::vec4(x, y, 0, 1.f);
-
-	glm::mat4 M = glm::inverse(cam.projection * cam.view);
-	glm::vec4 ray_start_world = M * ray_start_ndc;
-	glm::vec4 ray_end_world = M * ray_end_ndc;
-	ray_start_world /= ray_start_world.w;
-	ray_end_world /= ray_end_world.w;
-
-	glm::vec3 ray_origin = glm::vec3(ray_start_world);
-	glm::vec3 ray_dir = glm::normalize(glm::vec3(ray_end_world - ray_start_world));
-	return v3f(ray_dir.x, ray_dir.y, ray_dir.z);
-#else
-	// http://antongerdelan.net/opengl/raycasting.html
+	// NOTE: http://antongerdelan.net/opengl/raycasting.html
 	float x = 2.f * vp_coords.x / vp_dims.x - 1.f;
 	float y = 2.f * vp_coords.y / vp_dims.y - 1.f;
 	glm::vec4 ray_clip = glm::vec4(x, y, -1.f, 1.f);
 	glm::vec4 ray_eye = glm::inverse(cam.projection) * ray_clip;
 	ray_eye = glm::vec4(ray_eye.x, ray_eye.y, -1.f, 0); // NOTE: reset as ray
 	glm::vec4 ray_world = glm::normalize(glm::inverse(cam.view) * ray_eye);
+
 	return v3f(ray_world.x, ray_world.y, ray_world.z);
-#endif
 }
 
 bool
 cameraIntersectPlane(camera& cam, v3f ray, v3f plane_origin, v3f plane_normal, v3f& intersection)
 {
+	// NOTE: https://www.scratchapixel.com/lessons/3d-basic-rendering/minimal-ray-tracer-rendering-simple-shapes/ray-plane-and-ray-disk-intersection
 	glm::vec3 c_o = cam.position;
 	glm::vec3 r = convertv3f(ray);
-	//glm::vec3 r = cam.forward;
 	glm::vec3 p_o = convertv3f(plane_origin);
 	glm::vec3 p_n = convertv3f(plane_normal);
 	float divisor = glm::dot(r, p_n);
 
 	if (divisor <= 0.000001f && divisor >= -0.000001f) // NOTE: ray and plane are co-planar
 		return false;
-#if 1
+
 	float distance = glm::dot((p_o - c_o), p_n) / divisor;
 	glm::vec3 xsect = c_o + (r * distance);
-#else
-	float distance = glm::dot(n, (p_o - c_o)) / glm::dot(n, r);
-	glm::vec3 xsect = c_o + r * distance;
-#endif
 	intersection = v3f(xsect.x, xsect.y, xsect.z);
+
 	return true;
 }