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#include <iostream>
#include <chrono>
#include <thread>
#include <SDL.h>
#include "assets.h"
#include "fps_counter.h"
#include "map.h"
#include "player.h"
void main_loop(SDL_Renderer *renderer) {
FPS_Counter fps_counter(renderer);
Map map(renderer);
Player player(renderer);
TimeStamp timestamp = Clock::now();
while (true) { // main game loop
SDL_Event event; // handle window closing
if (SDL_PollEvent(&event) && (SDL_QUIT==event.type || (SDL_KEYDOWN==event.type && SDLK_ESCAPE==event.key.keysym.sym)))
break; // quit
player.handle_keyboard(); // no need for the event variable, direct keyboard state polling
const auto dt = Clock::now() - timestamp;
if (dt<std::chrono::milliseconds(20)) { // 50 FPS regulation
std::this_thread::sleep_for(std::chrono::milliseconds(1));
continue;
}
timestamp = Clock::now();
player.update_state(std::chrono::duration<double>(dt).count(), map); // gravity, movements, collision detection etc
SDL_RenderClear(renderer); // re-draw the window
fps_counter.draw();
player.draw();
map.draw();
SDL_RenderPresent(renderer);
}
} // N.B. fps_counter, map and player objects call their destructors here, thus destroying allocated textures, it must be done prior to destroying the renderer
int main() {
SDL_SetMainReady(); // tell SDL that we handle main() function ourselves, comes with the SDL_MAIN_HANDLED macro
if (SDL_Init(SDL_INIT_VIDEO)) {
std::cerr << "Failed to initialize SDL: " << SDL_GetError() << std::endl;
return -1;
}
SDL_Window *window = nullptr;
SDL_Renderer *renderer = nullptr;
if (SDL_CreateWindowAndRenderer(1024, 768, SDL_WINDOW_SHOWN | SDL_WINDOW_INPUT_FOCUS, &window, &renderer)) {
std::cerr << "Failed to create window and renderer: " << SDL_GetError() << std::endl;
return -1;
}
SDL_SetWindowTitle(window, "SDL2 game blank");
SDL_SetRenderDrawColor(renderer, 210, 255, 179, 255);
main_loop(renderer); // all interesting things happen here
SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
SDL_Quit();
return 0;
}
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