update shader logic to use multiple lights

data/default.fs

@@ -15,7 +15,7 @@ struct point_light {
 };
 #define MAX_LIGHTS 10
 uniform point_light lights[MAX_LIGHTS];
-uniform int num_lights = 0;
+uniform uint num_lights = 0u;
 
 out vec3 color;
 
@@ -23,19 +23,15 @@ void main()
 {
 	// https://www.tomdalling.com/blog/modern-opengl/06-diffuse-point-lighting
 	vec3 normal = normalize(normal_matrix * fragNormal);
-
 	vec3 fragPosition = vec3(model * vec4(fragVertex, 1));
+	float totalBrightness = 0;
 
-	/////
-
-	//vec3 surfaceToLight = light_position - fragPosition;
-	vec3 surfaceToLight = lights[0].position - fragPosition;
-
-	/////
-
-	float brightness = dot(normal, surfaceToLight) / (length(surfaceToLight) * length(normal));
-	brightness = clamp(brightness, 0, 1);
+	for (uint i = 0u; i < num_lights; i++) {
+		vec3 surfaceToLight = lights[i].position - fragPosition;
+		float brightness = dot(normal, surfaceToLight) / (length(surfaceToLight) * length(normal));
+		totalBrightness += brightness;
+	}
 
-	color = brightness * fragmentColor;
+	color = clamp(totalBrightness, 0, 1) * fragmentColor;
 }
 

data/test_scene.json

@@ -84,7 +84,21 @@
 			},
 
 			"position" : {
-				"x" : 0,
+				"x" : -400,
+				"y" : 0,
+				"z" : 100
+			}
+		},
+		{
+			"intensity" : 1.0,
+			"color" : {
+				"r" : 0,
+				"g" : 0,
+				"b" : 0
+			},
+
+			"position" : {
+				"x" : 200,
 				"y" : 0,
 				"z" : 100
 			}

src/hexgame.cpp

@@ -525,10 +525,10 @@ int main(int argc, char* argv[])
 		return 1;
 	}
 
-
-	// testing scene_loader
+	// load scene from json
 
 	slSceneDoc* sd = slLoadFile(DATA_DIR, DEFAULT_SCENE_FILE, SCENE_SCHEMA_FILE);
+
 	if (sd != nullptr) {
 		game_state* g = g_game_state;
 		render_state* rs = g_render_state;

src/render_group.cpp

@@ -331,13 +331,14 @@ drawRenderObject(render_group* rg, render_object* ro,
 		glBindBuffer(GL_ARRAY_BUFFER, ro->normal_buffer.buffer_id);
 		glVertexAttribPointer(2, 3, GL_FLOAT, GL_FALSE, 0, (void*) 0);
 
-		// TODO: testing lighting
+		glm::mat3 normal_matrix = glm::transpose(glm::inverse(glm::mat3(model_matrix)));
+		glUniformMatrix3fv(rg->shader.normal_matrix_id, 1, GL_FALSE, &normal_matrix[0][0]);
+
 		// TODO: use Uniform Buffer Objects to update light data
 		// 	https://www.khronos.org/registry/OpenGL/extensions/ARB/ARB_uniform_buffer_object.txt
 		// 	https://www.khronos.org/opengl/wiki/Uniform_Buffer_Objects
 
-		glm::mat3 normal_matrix = glm::transpose(glm::inverse(glm::mat3(model_matrix)));
-		glUniformMatrix3fv(rg->shader.normal_matrix_id, 1, GL_FALSE, &normal_matrix[0][0]);
+		glUniform1ui(rg->shader.num_lights_id, num_lights);
 
 		for (uint i = 0; i < num_lights; i++) {
 			// TODO: don't do this every frame * every render_group

src/renderer.cpp

@@ -67,9 +67,6 @@ static render_group* g_debug_render_group;
 static rg_shader_program g_default_shader;
 // NOTE: entity render_group pointers are kept in the entity struct
 static camera g_camera;
-
-// TODO: testing lighting
-//static renPointLight g_test_light;
 // TODO: maybe keep all these globals in the render_state object?
 
 
@@ -264,18 +261,6 @@ createScene(render_state* rs, std::vector<hex_info>* hexes, Entity* entities, ui
 	rgBufferData(&debug_color_buf, GL_STATIC_DRAW, GL_ARRAY_BUFFER);
 	rgBufferData(&debug_normal_buf, GL_STATIC_DRAW, GL_ARRAY_BUFFER);
 
-	// lights
-
-	// TODO: load light properties from scene/level files
-	// light testing
-#if 0
-	rs->lights[0].light_ID = 0;
-	rs->lights[0].position = glm::vec3(0.f, 0.f, 200.f);
-	rs->lights[0].color = glm::vec3(1.f, 1.f, 1.f);
-	rs->lights[0].intensity = 1.f;
-	rs->num_lights = 1;
-#endif
-
 	return true;
 }