diff options
| -rw-r--r-- | CMakeLists.txt | 6 | ||||
| -rw-r--r-- | src/main.cc (renamed from main.cc) | 93 |
2 files changed, 54 insertions, 45 deletions
diff --git a/CMakeLists.txt b/CMakeLists.txt index a16dced..4a89f50 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -7,12 +7,12 @@ set( ) add_executable( - shader - main.cc + computicle + src/main.cc ) target_link_libraries( - shader + computicle GL GLEW glfw @@ -7,8 +7,7 @@ #include <vector> #include <iostream> #include <random> - -GLFWwindow* window; +#include <chrono> GLint getUniform(GLuint program, const std::string& name) { const GLint uniform = glGetUniformLocation(program, name.c_str()); @@ -19,9 +18,9 @@ GLint getUniform(GLuint program, const std::string& name) { } GLint compileShader(const std::string& source, GLenum type) { - GLint local_shader = glCreateShader(type); + GLint shader = glCreateShader(type); - if ( !local_shader ) { + if ( !shader ) { std::cerr << "Cannot create a shader of type " << type << std::endl; exit(-1); } @@ -29,24 +28,24 @@ GLint compileShader(const std::string& source, GLenum type) { const char* source_data = source.c_str(); const int source_length = source.size(); - glShaderSource(local_shader, 1, &source_data, &source_length); - glCompileShader(local_shader); + glShaderSource(shader, 1, &source_data, &source_length); + glCompileShader(shader); GLint compiled; - glGetShaderiv(local_shader, GL_COMPILE_STATUS, &compiled); + glGetShaderiv(shader, GL_COMPILE_STATUS, &compiled); if ( !compiled ) { std::cerr << "Cannot compile shader" << std::endl; GLint maxLength = 0; - glGetShaderiv(local_shader, GL_INFO_LOG_LENGTH, &maxLength); + glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &maxLength); std::vector<GLchar> errorLog(maxLength); - glGetShaderInfoLog(local_shader, maxLength, &maxLength, &errorLog[0]); + glGetShaderInfoLog(shader, maxLength, &maxLength, &errorLog[0]); for( auto c : errorLog ) { std::cerr << c; } std::cerr << std::endl; } - return local_shader; + return shader; } GLint setupShader() { @@ -149,18 +148,36 @@ void cursor_pos_callback(GLFWwindow*, double x, double y) { mouse_y = world_height/2 - world_height * (y / window_height); } +std::vector<GLfloat> makeInitialParticles(std::size_t count) { + std::vector<GLfloat> buffer; + buffer.reserve(3*count); + + std::random_device rd; + std::mt19937 gen(rd()); + std::uniform_real_distribution<GLfloat> distX(-world_width/2., world_width/2.); + std::uniform_real_distribution<GLfloat> distY(-world_height/2., world_height/2.); + std::uniform_real_distribution<GLfloat> distAge(0., 5.); + + for ( std::size_t i = 0; i < count; ++i ) { + buffer.emplace_back(distX(gen)); + buffer.emplace_back(distY(gen)); + buffer.emplace_back(distAge(gen)); + } + + return buffer; +} + int main() { if( !glfwInit() ) { std::cerr << "Failed to initialize GLFW" << std::endl; return -1; } - glfwWindowHint(GLFW_SAMPLES, 4); glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3); glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3); glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE); - window = glfwCreateWindow(window_width, window_height, "shader", NULL, NULL); + GLFWwindow* const window = glfwCreateWindow(window_width, window_height, "computicle", NULL, NULL); if( window == NULL ){ std::cerr << "Failed to open GLFW window." << std::endl; glfwTerminate(); @@ -170,7 +187,6 @@ int main() { glfwSetCursorPosCallback(window, cursor_pos_callback); glfwMakeContextCurrent(window); - glewExperimental = true; if ( glewInit() != GLEW_OK ) { std::cerr << "Failed to initialize GLEW" << std::endl; glfwTerminate(); @@ -185,47 +201,40 @@ int main() { glGenVertexArrays(1, &VertexArrayID); glBindVertexArray(VertexArrayID); - GLint ProgramID = setupShader(); - GLuint MatrixID = glGetUniformLocation(ProgramID, "MVP"); - GLuint MouseID = glGetUniformLocation(ProgramID, "mouse"); + GLint ShaderID = setupShader(); + GLuint MatrixID = glGetUniformLocation(ShaderID, "MVP"); + GLuint MouseID = glGetUniformLocation(ShaderID, "mouse"); - GLint ComputeProgramID = setupComputeShader(); - GLuint WorldID = glGetUniformLocation(ComputeProgramID, "world"); + GLint ComputeShaderID = setupComputeShader(); + GLuint WorldID = glGetUniformLocation(ComputeShaderID, "world"); updateMVP(); - const std::size_t particle_count = 100000; + const std::size_t particle_count = 500000; - std::vector<GLfloat> vertex_buffer_data; - vertex_buffer_data.reserve(3*particle_count); - - std::random_device rd; - std::mt19937 gen(rd()); - std::uniform_real_distribution<GLfloat> distX(-world_width/2.f, world_width/2.f); - std::uniform_real_distribution<GLfloat> distY(-world_height/2.f, world_height/2.f); - std::uniform_real_distribution<GLfloat> distAge(0.f, 5.f); - - for ( int i = 0; i < particle_count; ++i ) { - vertex_buffer_data.emplace_back(distX(gen)); - vertex_buffer_data.emplace_back(distY(gen)); - vertex_buffer_data.emplace_back(distAge(gen)); - } + auto vertex_buffer_data = makeInitialParticles(particle_count); GLuint vertexbuffer; glGenBuffers(1, &vertexbuffer); glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer); - glBufferData(GL_ARRAY_BUFFER, - vertex_buffer_data.size() * sizeof(GLfloat), &vertex_buffer_data[0], GL_STATIC_DRAW); + glBufferData(GL_ARRAY_BUFFER, vertex_buffer_data.size() * sizeof(GLfloat), &vertex_buffer_data[0], GL_STATIC_DRAW); + + auto lastFrame = std::chrono::high_resolution_clock::now(); do { - glUseProgram(ComputeProgramID); - glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 1, vertexbuffer); - glUniform2f(WorldID, world_width, world_height); - glDispatchCompute(particle_count, 1, 1); + // update particles at most 50 times per second + if ( std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::high_resolution_clock::now() - lastFrame).count() >= 20 ) { + glUseProgram(ComputeShaderID); + glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 1, vertexbuffer); + glUniform2f(WorldID, world_width, world_height); + glDispatchCompute(particle_count, 1, 1); + + lastFrame = std::chrono::high_resolution_clock::now(); + } glClear(GL_COLOR_BUFFER_BIT); - glUseProgram(ProgramID); + glUseProgram(ShaderID); glUniformMatrix4fv(MatrixID, 1, GL_FALSE, &MVP[0][0]); glUniform2f(MouseID, mouse_x, mouse_y); @@ -246,8 +255,8 @@ int main() { glDeleteBuffers(1, &vertexbuffer); glDeleteVertexArrays(1, &VertexArrayID); - glDeleteProgram(ProgramID); - glDeleteProgram(ComputeProgramID); + glDeleteProgram(ShaderID); + glDeleteProgram(ComputeShaderID); glfwTerminate(); |