src/Main.cpp

@@ -8,7 +8,10 @@
 
 #include <chrono>
 
-constexpr int PARTICLE_COUNT = 64 * 5000;
+constexpr int WORK_GROUP_SIZE = 64;
+constexpr int PARTICLE_COUNT = WORK_GROUP_SIZE * 1000;
+
+constexpr int SWAP_INTERVAL = 60;
 
 class Timer {
   public:
@@ -51,6 +54,7 @@ static void KeyCallback(GLFWwindow* window, int key, int scancode, int action, i
 	if (key == GLFW_KEY_R) {
 		s_ComputeShader = ReloadComputeShader(s_ComputeShader, s_ComputeShaderPath);
 		s_GraphicsShader = ReloadGraphicsShader(s_GraphicsShader, s_VertexShaderPath, s_FragmentShaderPath);
+		glBufferData(GL_SHADER_STORAGE_BUFFER, sizeof(float) * PARTICLE_COUNT * 2, nullptr, GL_DYNAMIC_COPY);
 	}
 }
 
@@ -72,12 +76,12 @@ static GLuint CreateDummyVAO() {
 	return vertexArray;
 }
 
-static void CreateGpuBuffer(std::size_t a_Size) {
+static void CreateGpuBuffer() {
 	GLuint ssbo;
 	glGenBuffers(1, &ssbo);
 	glBindBuffer(GL_SHADER_STORAGE_BUFFER, ssbo);
 	glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 3, ssbo);
-	glBufferData(GL_SHADER_STORAGE_BUFFER, sizeof(float) * a_Size, nullptr,
+	glBufferData(GL_SHADER_STORAGE_BUFFER, sizeof(float) * 2 * PARTICLE_COUNT, nullptr,
 		GL_DYNAMIC_COPY);  // sizeof(data) only works for statically sized C/C++ arrays.
 }
 
@@ -103,7 +107,7 @@ static GLFWwindow* InitWindow() {
 
 	glfwMakeContextCurrent(window);
 	gladLoadGL();
-	glfwSwapInterval(1);
+	glfwSwapInterval(SWAP_INTERVAL);
 
 	s_ComputeShader = CreateComputeShader(s_ComputeShaderPath);
 	if (s_ComputeShader == -1) {
@@ -127,7 +131,7 @@ int main() {
 
 	auto vertexArray = CreateDummyVAO();
 
-	CreateGpuBuffer(PARTICLE_COUNT);
+	CreateGpuBuffer();
 
 	float lastTime = (float)glfwGetTime();
 
@@ -154,7 +158,7 @@ int main() {
 
 		// Compute
 		glUseProgram(s_ComputeShader);
-		glDispatchCompute(PARTICLE_COUNT / 64, 1, 1);
+		glDispatchCompute(PARTICLE_COUNT / WORK_GROUP_SIZE, 1, 1);
 
 		// Ensure all writes to the image are complete
 		glMemoryBarrier(GL_SHADER_IMAGE_ACCESS_BARRIER_BIT);