sdlboilerplate.cpp

#include <stdio.h>
#include <SDL.h>
#include <GL/glew.h>
#include <math.h>

#define BTN_QUIT 256
#define BTN_MOUSE0 257
#define BTN_MOUSE1 258
#define BTN_MOUSE2 259
#define BTN_MOUSE3 260
#define BTN_MOUSE4 261
#define BTN_MOUSE_LEFT 258
#define BTN_MOUSE_RIGHT 260

SDL_Window* win = 0;
SDL_GLContext ctx;
int done = 0;
int grab = 0;
int w=1440, h=810;
int resized = 1;
int omx=0, omy=0;

void inputMotion(float x, float y) {}
void inputButton(int btn, int state) {}
void render() {
    glClearColor(0,0,0,0);
    glClear(GL_COLOR_BUFFER_BIT);
}

int main() {
    SDL_Init(SDL_INIT_EVERYTHING);
    win = SDL_CreateWindow("sdlboilerplate", 0, 0, w, h, SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE);
    ctx = SDL_GL_CreateContext(win);
    glewInit();
    SDL_GetMouseState(&omx, &omy);
    SDL_GetWindowSize(win, &w, &h);
    while (!done) {
        SDL_Event e;
        while (SDL_PollEvent(&e)) {
            switch (e.type) {
                case SDL_WINDOWEVENT:
                    if (e.window.event == SDL_WINDOWEVENT_SIZE_CHANGED) {
                        w = e.window.data1;
                        h = e.window.data2;
                        resized = 1;
                    }
                    break;
                case SDL_QUIT:
                    if (!grab) done = 1;
                    inputButton(BTN_QUIT, 1);
                    break;
                case SDL_MOUSEBUTTONDOWN:
                    inputButton(BTN_MOUSE0 + e.button.button, 1);
                    break;
                case SDL_MOUSEBUTTONUP:
                    inputButton(BTN_MOUSE0 + e.button.button, 0);
                    break;
                case SDL_KEYDOWN:
                    inputButton(e.key.keysym.sym, 1);
                    break;
                case SDL_KEYUP:
                    inputButton(e.key.keysym.sym, 0);
                    break;
            }
        }
        if (grab) {
            int mx=0, my=0;
            SDL_GetMouseState(&mx, &my);
            mx -= w/2;
            my -= h/2;
            if (mx*mx+my*my >= 8) {
                SDL_WarpMouseInWindow(win, w/2, h/2);
                inputMotion(mx, my);
            }
        }
        render();
        SDL_GL_SwapWindow(win);
        SDL_Delay(1);
    }
    SDL_GL_DeleteContext(ctx);
    SDL_DestroyWindow(win);
    return 0;
}