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-rw-r--r--gl-vfog/main.cc281
1 files changed, 0 insertions, 281 deletions
diff --git a/gl-vfog/main.cc b/gl-vfog/main.cc
deleted file mode 100644
index 679d4ec..0000000
--- a/gl-vfog/main.cc
+++ /dev/null
@@ -1,281 +0,0 @@
-// OpenGL volumetric fog demo
-//
-// SPDX-License-Identifier: 0BSD
-//
-// Changelog:
-// - 11/13/25: Initial release
-//
-
-#define GLAD_GL_IMPLEMENTATION
-#include "../common/c_cpp/thirdparty/glad33/glad33.h"
-
-#include <SDL3/SDL.h>
-#include <SDL3/SDL_main.h>
-#include <SDL3/SDL_opengl.h>
-
-#define IMGUI_IMPL_OPENGL_LOADER_CUSTOM
-#include "imgui.h"
-#include "imgui_impl_opengl3.cpp"
-#include "imgui_impl_sdl3.cpp"
-
-#include "geometry.hh"
-
-// Helper: Report errors via glGetError() after every OpenGL function call.
-// macOS does not support glDebugMessageCallback
-static void assert_gl_error(GLenum error, const char* expr, int line)
-{
- if (error != GL_NO_ERROR) {
- const char* error_string;
- switch (error) {
-#define BIND_ERROR(name) case name: { error_string = #name; }; break;
- BIND_ERROR(GL_INVALID_ENUM);
- BIND_ERROR(GL_INVALID_VALUE);
- BIND_ERROR(GL_INVALID_OPERATION);
- BIND_ERROR(GL_INVALID_FRAMEBUFFER_OPERATION);
- BIND_ERROR(GL_OUT_OF_MEMORY);
-#undef BIND_ERROR
- default: SDL_assert(0 && "Invalid GL_ERROR enum");
- }
- SDL_Log("[Line #%u] %s caused %s\n", line, expr, error_string);
- }
-}
-#define GL(expr) \
- expr; \
- for (GLenum _glcode; (_glcode = glGetError()) != GL_NO_ERROR; ) { \
- assert_gl_error(_glcode, #expr, __LINE__); \
- }
-
-int main(int argc, char* argv[])
-{
- (void)argc;
- (void)argv;
-
- if (!SDL_Init(SDL_INIT_VIDEO | SDL_INIT_EVENTS)) {
- fprintf(stderr, "Failed to initialize SDL: %s\n", SDL_GetError());
- return EXIT_FAILURE;
- }
-
- SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
- SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 3);
- SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
- SDL_GL_SetAttribute(SDL_GL_MULTISAMPLEBUFFERS, 1);
- SDL_GL_SetAttribute(SDL_GL_MULTISAMPLESAMPLES, 4);
-
- SDL_Window* wnd = SDL_CreateWindow("gl-vfog", 1024, 768, SDL_WINDOW_OPENGL);
- if (!wnd) {
- fprintf(stderr, "Failed to create window: %s\n", SDL_GetError());
- return EXIT_FAILURE;
- }
-
- if (!SDL_GL_CreateContext(wnd)) {
- fprintf(stderr, "Failed to create OpenGL context: %s\n", SDL_GetError());
- return EXIT_FAILURE;
- }
- SDL_GL_SetSwapInterval(1);
-
- if (!gladLoadGL(SDL_GL_GetProcAddress)) {
- fprintf(stderr, "Failed to load OpenGL functions\n");
- return EXIT_FAILURE;
- }
-
- IMGUI_CHECKVERSION();
- ImGui::CreateContext();
- ImGui_ImplSDL3_Init(wnd, 0, 0);
- ImGui_ImplOpenGL3_Init();
- ImGui::GetIO().IniFilename = NULL;
-
- //
- // 0 1
- // +------------+
- // /| /|
- // 4 / | 5 / |
- // +------------+ |
- // | | | |
- // | | 3 | | 2
- // | +---------|--+
- // | / | /
- // 7 |/ 6 |/
- // +------------+
- //
-
- const float vdata[] = {
- 0.0f, 1.0f, 0.0f,
- 1.0f, 1.0f, 0.0f,
- 1.0f, 0.0f, 0.0f,
- 0.0f, 0.0f, 0.0f,
- 0.0f, 1.0f, 1.0f,
- 1.0f, 1.0f, 1.0f,
- 1.0f, 0.0f, 1.0f,
- 0.0f, 0.0f, 1.0f,
- };
-
- const uint16_t idata[] = {
- 1, 0, 3,
- 1, 3, 2,
- 5, 1, 2,
- 5, 2, 6,
- 4, 5, 6,
- 4, 6, 7,
- 0, 4, 7,
- 0, 7, 3,
- 0, 1, 5,
- 0, 5, 4,
- 7, 6, 2,
- 7, 2, 3,
- };
-
- GLuint vao;
- GL(glGenVertexArrays(1, &vao))
- GL(glBindVertexArray(vao));
-
- GLuint vbo;
- GL(glGenBuffers(1, &vbo));
- GL(glBindBuffer(GL_ARRAY_BUFFER, vbo));
- GL(glBufferData(GL_ARRAY_BUFFER, sizeof(vdata), vdata, GL_STATIC_DRAW));
-
- GLuint ibo;
- GL(glGenBuffers(1, &ibo));
- GL(glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ibo));
- GL(glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(idata), idata, GL_STATIC_DRAW));
-
- GL(glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, sizeof(float) * 3, NULL));
- GL(glEnableVertexAttribArray(0));
-
- struct {
- GLenum type;
- const char* path;
- } shaders[] = {
- { .type = GL_VERTEX_SHADER, .path = "vs.glsl" },
- { .type = GL_FRAGMENT_SHADER, .path = "fs.glsl" },
- };
-
- GLuint prog = GL(glCreateProgram());
- for (size_t i = 0; i < sizeof(shaders) / sizeof(*shaders); ++i) {
- const char* src = (const char*)SDL_LoadFile(shaders[i].path, NULL);
- if (!src) {
- fprintf(stderr, "Failed to load shader %s: %s\n", shaders[i].path, SDL_GetError());
- return EXIT_FAILURE;
- }
-
- GLuint shader = GL(glCreateShader(shaders[i].type));
- GL(glShaderSource(shader, 1, &src, NULL));
- GL(glCompileShader(shader));
- GLint compile_status = 0;
- GL(glGetShaderiv(shader, GL_COMPILE_STATUS, &compile_status));
- if (compile_status != GL_TRUE) {
- char error[1024] = { 0 };
- GL(glGetShaderInfoLog(shader, sizeof(error), NULL, error));
- SDL_Log("Error compiling shader %s: %s\n", shaders[i].path, error);
- return EXIT_FAILURE;
- }
- GL(glAttachShader(prog, shader));
- }
- GL(glLinkProgram(prog));
-
- GLint prog_status;
- GL(glGetProgramiv(prog, GL_LINK_STATUS, &prog_status));
- if (prog_status != GL_TRUE) {
- char error[1024] = { 0 };
- GL(glGetProgramInfoLog(prog, sizeof(error), NULL, error));
- SDL_Log("Error linking program: %s\n", error);
- return EXIT_FAILURE;
- }
-
- GL(glUseProgram(prog));
-
- GLuint u_view = GL(glGetUniformLocation(prog, "u_view"));
- GLuint u_cam = GL(glGetUniformLocation(prog, "u_cam"));
- GLuint u_time = GL(glGetUniformLocation(prog, "u_time"));
- GLuint u_mode = GL(glGetUniformLocation(prog, "u_mode"));
- GLuint u_sigma = GL(glGetUniformLocation(prog, "u_sigma"));
- GLuint u_steps = GL(glGetUniformLocation(prog, "u_steps"));
-
- bool running = true;
- while (running) {
- SDL_Event evt = { 0 };
- while (SDL_PollEvent(&evt)) {
- ImGui_ImplSDL3_ProcessEvent(&evt);
- switch (evt.type) {
- case SDL_EVENT_QUIT: {
- running = false;
- } break;
- }
- }
-
- int wnd_x = 0;
- int wnd_y = 0;
- SDL_GetWindowSizeInPixels(wnd, &wnd_x, &wnd_y);
-
- ImGui_ImplSDL3_NewFrame();
- ImGui_ImplOpenGL3_NewFrame();
- ImGui::NewFrame();
-
- // Controls
- static int c_mode = 0;
- static float c_sigma = 4.0f;
- static float c_zoom = 1.5f;
- static int c_steps = 64;
- ImGui::SetNextWindowPos(ImVec2(15, 15));
- ImGui::SetNextWindowSize(ImVec2(150, 768 - 30));
- if (ImGui::Begin("Controls", NULL, ImGuiWindowFlags_NoTitleBar | ImGuiWindowFlags_NoResize)) {
- ImGui::SeparatorText("Controls");
- ImGui::DragFloat("Zoom", &c_zoom, 0.05f, 0.1f, 3.0f);
- ImGui::SeparatorText("Settings");
- const char* modes[] = { "Basic", "Fade", "Waves", };
- if (ImGui::BeginCombo("Mode", modes[c_mode])) {
- for (int i = 0; i < IM_ARRAYSIZE(modes); ++i) {
- if (ImGui::Selectable(modes[i], i == c_mode)) {
- c_mode = i;
- }
- }
- ImGui::EndCombo();
- }
- ImGui::DragInt("Steps", &c_steps);
- ImGui::DragFloat("Sigma", &c_sigma, 0.05);
- ImGui::End();
- }
-
- GL(glViewport(0, 0, wnd_x, wnd_y));
- GL(glEnable(GL_CULL_FACE));
- GL(glCullFace(GL_FRONT));
- GL(glEnable(GL_DEPTH_TEST));
- GL(glEnable(GL_BLEND));
- GL(glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA));
- GL(glClearColor(0.1f, 0.1f, 0.1f, 1.0f));
- GL(glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT));
-
- const float t = SDL_GetTicks() / 1e3f;
- const float camt = t * 0.33f;
-
- Vec3 eye = Vec3(0.0f, 1.5f, 0.0f);
- Vec3 tgt = Vec3(0.5f, 0.5f, 0.5f);
- eye.x = tgt.x + SDL_sinf(camt) * c_zoom;
- eye.z = tgt.z + SDL_cosf(camt) * c_zoom;
- Vec3 up = Vec3(0.0f, 1.0f, 0.0f);
-
- Mat4x4 look = Mat4x4::LookAt(eye, tgt, up);
- Mat4x4 proj = Mat4x4::Perspective(70.0f, (float)wnd_x / (float)wnd_y, 0.1f, 10.0f);
- Mat4x4 view = proj * look;
-
- GL(glUniformMatrix4fv(u_view, 1, GL_FALSE, view.Base()))
- GL(glUniform3fv(u_cam, 1, eye.Base()));
- GL(glUniform1f(u_time, t));
- GL(glUniform1i(u_mode, c_mode));
- GL(glUniform1f(u_sigma, c_sigma));
- GL(glUniform1i(u_steps, c_steps));
-
- GL(glDrawElements(GL_TRIANGLES, 3 * 12, GL_UNSIGNED_SHORT, NULL));
-
- ImGui::Render();
- ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
-
- if (!SDL_GL_SwapWindow(wnd)) {
- fprintf(stderr, "Failed to present window: %s", SDL_GetError());
- return EXIT_FAILURE;
- }
- }
-
- SDL_DestroyWindow(wnd);
-
- return EXIT_SUCCESS;
-}
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