Shaders/Compute.glsl

@@ -1,7 +1,7 @@
 #version 460 core
 
 layout(std430, binding = 3) buffer layoutName {
-  vec2 o_Points[];
+  float o_Points[];
 };
 
 layout(local_size_x = 64) in;
@@ -16,23 +16,35 @@ highp float rand(vec2 co)
     return fract(sin(sn) * c);
 }
 
+vec3 unpack(uint index) {
+	return vec3(o_Points[index * 3], o_Points[index * 3 + 1], o_Points[index * 3 + 2]);
+}
+
+void store(vec3 vect, uint index) {
+	o_Points[index * 3] = vect.x;
+	o_Points[index * 3 + 1] = vect.y;
+	o_Points[index * 3 + 2] = vect.z;
+}
+
 void main() {
 	const uint total = gl_NumWorkGroups.x * gl_WorkGroupSize.x;
-    uint currentPoint = gl_GlobalInvocationID.x;
-	uint index = uint(rand(o_Points[currentPoint] + currentPoint) * 69);
-	mat3 transformation;
+    uint currentIndex = gl_GlobalInvocationID.x;
+	vec3 currentPoint = unpack(currentIndex);
+	uint index = uint(rand(currentPoint.xy + currentPoint.z + currentIndex) * 69);
+	mat4 transformation;
 	switch (index % 3) {
 		case 0:
-			transformation = mat3(0.5, 0, 0, 0, 0.5, 0, 0, 0.36, 1);
+			transformation = mat4(0.5, 0, 0, 0,   0, 0.5, 0, 0,  0, 0, 0, 0,   0, 0.36, 0, 1);
 			break;
 
 		case 1:
-			transformation = mat3(0.5, 0, 0, 0, 0.5, 0, -0.5, -0.5, 1);
+			transformation = mat4(0.5, 0, 0, 0,   0, 0.5, 0, 0,  0, 0, 0, 0,   -0.5, -0.5, 0, 1);
 			break;
 
 		case 2:
-			transformation = mat3(0.5, 0, 0, 0, 0.5, 0, 0.5, -0.5, 1);
+			transformation = mat4(0.5, 0, 0, 0,   0, 0.5, 0, 0,  0, 0, 0, 0,   0.5, -0.5, 0, 1);
 			break;
 	}
-	o_Points[currentPoint] = (transformation * vec3(o_Points[currentPoint], 1.0)).xy;
+	vec3 result = (transformation * vec4(currentPoint, 1.0)).xyz;
+	store(result, currentIndex);
 }

Shaders/Vertex.glsl

@@ -2,10 +2,14 @@
 
 layout(std430, binding = 3) buffer layoutName
 {
-    vec2 data_SSBO[];
+    float data_SSBO[];
 };
 
+vec3 unpack(uint index) {
+	return vec3(data_SSBO[index * 3], data_SSBO[index * 3 + 1], data_SSBO[index * 3 + 2]);
+}
+
 void main()
 {
-	gl_Position = vec4(data_SSBO[gl_InstanceID], 0.0, 1.0);
+	gl_Position = vec4(unpack(gl_InstanceID), 1.0);
 }

src/Main.cpp

@@ -54,7 +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);
+		glBufferData(GL_SHADER_STORAGE_BUFFER, sizeof(float) * PARTICLE_COUNT * 3, nullptr, GL_DYNAMIC_COPY);
 	}
 }
 
@@ -66,11 +66,11 @@ static GLuint CreateDummyVAO() {
 	glCreateBuffers(1, &vertexBuffer);
 
 	// Buffer with just one point
-	float vertices[] = {0.0f, 0.0f};
+	float vertices[] = {0.0f, 0.0f, 0.0f};
 	glNamedBufferData(vertexBuffer, sizeof(vertices), vertices, GL_STATIC_DRAW);
-	glVertexArrayVertexBuffer(vertexArray, 0, vertexBuffer, 0, sizeof(float) * 2);
+	glVertexArrayVertexBuffer(vertexArray, 0, vertexBuffer, 0, sizeof(float) * 3);
 	glEnableVertexArrayAttrib(vertexArray, 0);
-	glVertexArrayAttribFormat(vertexArray, 0, 2, GL_FLOAT, GL_FALSE, 0);
+	glVertexArrayAttribFormat(vertexArray, 0, 3, GL_FLOAT, GL_FALSE, 0);
 	glVertexArrayAttribBinding(vertexArray, 0, 0);
 
 	return vertexArray;
@@ -81,7 +81,7 @@ static void CreateGpuBuffer() {
 	glGenBuffers(1, &ssbo);
 	glBindBuffer(GL_SHADER_STORAGE_BUFFER, ssbo);
 	glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 3, ssbo);
-	glBufferData(GL_SHADER_STORAGE_BUFFER, sizeof(float) * 2 * PARTICLE_COUNT, nullptr,
+	glBufferData(GL_SHADER_STORAGE_BUFFER, sizeof(float) * 3 * PARTICLE_COUNT, nullptr,
 		GL_DYNAMIC_COPY);  // sizeof(data) only works for statically sized C/C++ arrays.
 }
 
@@ -174,6 +174,16 @@ int main() {
 		glClear(GL_COLOR_BUFFER_BIT);
 		glClearColor(0, 0, 0, 1);
 
+		// float positions[3 * PARTICLE_COUNT];
+		// glGetBufferSubData(GL_SHADER_STORAGE_BUFFER, 0, sizeof(float) * 3 * PARTICLE_COUNT, positions);
+
+		// std::cout << "Positions :\n";
+		// for (size_t i = 0; i < PARTICLE_COUNT; i++)
+		// {
+		// 	std::cout << "\t" << positions[i * 3] << " " << positions[i * 3 + 1] << " " << positions[i * 3 + 2] << "\n";
+		// }
+		
+
 		fps++;
 	}