procedurally generated transformations

src/Main.cpp

@@ -7,12 +7,72 @@
 #include "Shader.h"
 
 #include <chrono>
+#include <random>
 
 constexpr int WORK_GROUP_SIZE = 64;
 constexpr int PARTICLE_COUNT = WORK_GROUP_SIZE * 10000;
 
 constexpr int SWAP_INTERVAL = 1;
 
+constexpr int TRANSFORMATION_COUNT = 3;
+
+static const std::vector<glm::mat4> SIERPINSKI_TRIANGLE = {
+	{
+		0.5f,
+		0.0f,
+		0.0f,
+		0.0f,
+		0.0f,
+		0.5f,
+		0.0f,
+		0.36f,
+		0.0f,
+		0.0f,
+		0.0f,
+		0.0f,
+		0.0f,
+		0.0f,
+		0.0f,
+		1.0f,
+	},
+	{
+		0.5f,
+		0.0f,
+		0.0f,
+		-0.5f,
+		0.0f,
+		0.5f,
+		0.0f,
+		-0.5f,
+		0.0f,
+		0.0f,
+		0.0f,
+		0.0f,
+		0.0f,
+		0.0f,
+		0.0f,
+		1.0f,
+	},
+	{
+		0.5f,
+		0.0f,
+		0.0f,
+		0.5f,
+		0.0f,
+		0.5f,
+		0.0f,
+		-0.5f,
+		0.0f,
+		0.0f,
+		0.0f,
+		0.0f,
+		0.0f,
+		0.0f,
+		0.0f,
+		1.0f,
+	},
+};
+
 class Timer {
   public:
 	Timer() {
@@ -44,6 +104,54 @@ static void ErrorCallback(int error, const char* description) {
 	std::cerr << "Error: " << description << std::endl;
 }
 
+static void ApplyTransforms(const std::vector<glm::mat4>& transformations) {
+	glUseProgram(s_ComputeShader);
+	glUniformMatrix4fv(1, transformations.size(), true, glm::value_ptr(transformations[0]));
+}
+
+static void GenNewFractal() {
+	std::random_device randomDevice;
+	std::mt19937 generator(randomDevice());
+	std::uniform_real_distribution<float> distrib(0, 1);
+
+	// scale, rotation, shear, translation
+
+	std::vector<glm::mat4> transformations(TRANSFORMATION_COUNT);
+
+	for (std::size_t i = 0; i < transformations.size(); i++) {
+		float scaleX = distrib(generator);
+		float scaleY = distrib(generator);
+		float scaleZ = distrib(generator);
+
+		float rotX = distrib(generator) * 2 * 3.14;
+		float rotY = distrib(generator) * 2 * 3.14;
+		float rotZ = distrib(generator) * 2 * 3.14;
+
+		float shearXY = distrib(generator) * 0.2f - 0.1f;
+		float shearXZ = distrib(generator) * 0.2f - 0.1f;
+		float shearYX = distrib(generator) * 0.2f - 0.1f;
+		float shearYZ = distrib(generator) * 0.2f - 0.1f;
+		float shearZX = distrib(generator) * 0.2f - 0.1f;
+		float shearZY = distrib(generator) * 0.2f - 0.1f;
+
+		float translateX = distrib(generator) * 2.0f - 1.0f;
+		float translateY = distrib(generator) * 2.0f - 1.0f;
+		float translateZ = distrib(generator) * 2.0f - 1.0f;
+
+		auto scale = glm::scale(glm::mat4(1), {scaleX, scaleY, scaleZ});
+		auto rotateX = glm::rotate(scale, rotX, {1, 0, 0});
+		auto rotateY = glm::rotate(rotateX, rotY, {0, 1, 0});
+		auto rotateZ = glm::rotate(rotateY, rotZ, {0, 0, 1});
+		auto shear = glm::shear(rotateZ, {0, 0, 0}, {shearXY, shearXZ}, {shearYX, shearYZ}, {shearZX, shearZY});
+		auto translate = glm::translate(shear, {translateX, translateY, translateZ});
+
+		transformations[i] = translate;
+	}
+
+	glUseProgram(s_ComputeShader);
+	glUniformMatrix4fv(1, transformations.size(), false, glm::value_ptr(transformations[0]));
+}
+
 static void KeyCallback(GLFWwindow* window, int key, int scancode, int action, int mods) {
 	if (action != GLFW_PRESS)
 		return;
@@ -55,6 +163,11 @@ static void KeyCallback(GLFWwindow* window, int key, int scancode, int action, i
 		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 * 3, nullptr, GL_DYNAMIC_COPY);
+		ApplyTransforms(SIERPINSKI_TRIANGLE);
+	}
+
+	if (key == GLFW_KEY_T) {
+		GenNewFractal();
 	}
 }
 
@@ -140,30 +253,7 @@ int main() {
 
 	glBindVertexArray(vertexArray);
 
-	std::vector<glm::mat4> transformations = {
+	ApplyTransforms(SIERPINSKI_TRIANGLE);
-		{
-			0.5f, 0.0f, 0.0f, 0.0f,
-			0.0f, 0.5f, 0.0f, 0.36f,
-			0.0f, 0.0f, 0.0f, 0.0f,
-			0.0f, 0.0f, 0.0f, 1.0f,
-		},
-		{
-			0.5f, 0.0f, 0.0f, -0.5f,
-			0.0f, 0.5f, 0.0f, -0.5f,
-			0.0f, 0.0f, 0.0f, 0.0f,
-			0.0f, 0.0f, 0.0f, 1.0f,
-		},
-		{
-			0.5f, 0.0f, 0.0f, 0.5f,
-			0.0f, 0.5f, 0.0f, -0.5f,
-			0.0f, 0.0f, 0.0f, 0.0f,
-			0.0f, 0.0f, 0.0f, 1.0f,
-		},
-	};
-
-	glUseProgram(s_ComputeShader);
-	glUniformMatrix4fv(1, transformations.size(), true, glm::value_ptr(transformations[0]));
-
 
 	while (!glfwWindowShouldClose(window)) {
 		// ScopedTimer timer("Main Loop");
@@ -211,7 +301,6 @@ int main() {
 		// {
 		// 	std::cout << "\t" << positions[i * 3] << " " << positions[i * 3 + 1] << " " << positions[i * 3 + 2] << "\n";
 		// }
-		
 
 		fps++;
 	}