Add viewer

viewer/main.cpp

@@ -1,7 +1,213 @@
-//
-// Created by kai on 07/02/23.
-//
+#include <cstdlib>
+#include <SDL2/SDL.h>
+#include <SDL2_rotozoom.h>
+#include <SDL2_framerate.h>
+#include <vector>
+#include <unistd.h>
+#include "definitions.hpp"
+#include "particle.hpp"
+
 
 int main() {
+    double dt = 0.01;
+    double t = 1.0;
+    size_t current_idx = 1;
+    bool pause = true;
+
+    // Toggles
+
+    bool show_fps = false;
+    bool show_help = true;
+    bool show_zoom = true;
+    bool show_state = true;
+    bool show_speed = true;
+    bool show_grid = true;
+    bool auto_size = true;
+    bool shift = false;
+    bool ctrl = false;
+
+    bool update_required = true;
+
+    // Init SDL
+
+    SDL_Init(SDL_INIT_VIDEO);
+
+    SDL_Window* window = SDL_CreateWindow("Verlet", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 800, 800, SDL_WINDOW_SHOWN);
+
+    SDL_Event event;
+
+    SDL_Surface* surf = SDL_CreateRGBSurface(0, 800, 800, 32, 0, 0, 0, 0);
+
+    std::vector<Particle> particles;
+
+    FPSmanager fps;
+
+    SDL_initFramerate(&fps);
+    SDL_setFramerate(&fps, 60);
+
+    float max_dim = 0.0;
+
+    while (true) {
+        while (SDL_PollEvent(&event)) {
+            if (event.type == SDL_QUIT) {
+                exit(0);
+            } else if (event.type == SDL_KEYDOWN) {
+                switch (event.key.keysym.sym) {
+                    case SDLK_RSHIFT:
+                    case SDLK_LSHIFT:
+                        shift = true;
+                        break;
+
+                    case SDLK_RCTRL:
+                    case SDLK_LCTRL:
+                        ctrl = true;
+                        break;
+
+                    case SDLK_SPACE:
+                        pause = !pause;
+                        printf("Paused: %s\n", pause ? "true" : "false");
+                        break;
+
+                    case SDLK_LEFT:
+                        t -= dt;
+                        current_idx = (int)t;
+                        update_required = true;
+                        break;
+
+                    case SDLK_RIGHT:
+                        t += dt;
+                        current_idx = (int)t;
+                        update_required = true;
+                        break;
+
+                    case SDLK_KP_PLUS:
+                        dt *= 2;
+                        printf("dt: %f\n", dt);
+                        break;
+
+                    case SDLK_KP_MINUS:
+                        dt /= 2;
+                        printf("dt: %f\n", dt);
+                        break;
+
+                    case SDLK_KP_0:
+                        t = 1;
+                        current_idx = 1;
+                        update_required = true;
+                        break;
+
+                    case SDLK_UP:
+                        if (shift) {
+                            max_dim -= 1;
+                        } else if (ctrl) {
+                            max_dim -= 10;
+                        } else {
+                            max_dim -= 0.1;
+                        }
+                        update_required = true;
+                        break;
+
+                    case SDLK_DOWN:
+                        if (shift) {
+                            max_dim += 1;
+                        } else if (ctrl) {
+                            max_dim += 10;
+                        } else {
+                            max_dim += 0.1;
+                        }
+                        update_required = true;
+                        break;
+
+                    case SDLK_a:
+                        auto_size = !auto_size;
+                        update_required = true;
+                        printf("Auto size: %s\n", auto_size ? "true" : "false");
+                        break;
+                }
+            } else if (event.type == SDL_KEYUP) {
+                switch (event.key.keysym.sym) {
+                    case SDLK_RSHIFT:
+                    case SDLK_LSHIFT:
+                        shift = false;
+                        break;
+
+                    case SDLK_RCTRL:
+                    case SDLK_LCTRL:
+                        ctrl = false;
+                        break;
+                }
+            }
+        }
+
+        if (!pause) {
+            t += dt;
+            current_idx = (int)t;
+            update_required = true;
+        }
+
+        if (update_required) {
+            SDL_FillRect(surf, nullptr, SDL_MapRGB(surf->format, 0, 0, 0));
+            particles.clear();
+
+            char filename[256];
+            sprintf(filename, "./output/%zu.dat", current_idx);
+
+            FILE* f = fopen(filename, "rb");
+
+            if (f == nullptr) {
+                printf("File not found: %s\n", filename);
+                printf("End of simulation\n");
+                pause = true;
+            } else {
+
+                char *cur_line = (char *)malloc(64 * sizeof(char));
+                size_t len = 64;
+
+                while (true) {
+                    if (getline(&cur_line, &len, f) <= 0) {
+                        break;
+                    }
+
+                    float x, y, vx, vy, m;
+
+                    if (sscanf(cur_line, "%f %f %f %f %f", &x, &y, &vx, &vy, &m) != 5) {
+                        break;
+                    }
+
+                    particles.push_back(Particle{m, {x, y}, {vx, vy}});
+                }
+
+                fclose(f);
+
+                if (auto_size) {
+                    for (auto &particle: particles) {
+                        max_dim = std::max(max_dim,
+                                           std::max(std::abs(particle.position.x), std::abs(particle.position.y)));
+                    }
+                }
+
+                for (auto &particle: particles) {
+                    particle.position /= (max_dim * 1.1);
+                    particle.position *= 400.0;
+                    particle.position += vec2(400, 400);
+
+                    SDL_Rect rect = {(int) particle.position.x - 1, (int) particle.position.y - 1, 2, 2};
+
+                    SDL_FillRect(surf, &rect, SDL_MapRGB(surf->format, 255, 255, 255));
+                }
+            }
+
+            update_required = false;
+        }
+
+        SDL_framerateDelay(&fps);
+
+        SDL_Surface* window_surface = SDL_GetWindowSurface(window);
+
+        SDL_BlitSurface(surf, NULL, window_surface, NULL);
+
+        SDL_UpdateWindowSurface(window);
+    }
+
     return 0;
 }