void rotate_point(float cx, float cy, float angle, int *px,int *py) {

    *px = cos(angle) * (*px - cx) - sin(angle) * (*py - cy) + cx;
    *py = sin(angle) * (*px - cx) + cos(angle) * (*py - cy) + cy;
}
int main(int argc, char* argv[])
{
    if (SDL_Init(SDL_INIT_EVERYTHING) < 0)
    {
        std::cout << "SDL initialization failed. SDL Error: " << SDL_GetError();
    }
    else
    {
        std::cout << "SDL initialization succeeded!";
    }

    SDL_Surface* screen_surface = NULL;
    SDL_Window* window = SDL_CreateWindow("", SDL_WINDOWPOS_UNDEFINED,
        SDL_WINDOWPOS_UNDEFINED, 1024, 768,
        SDL_WINDOW_SHOWN);
    SDL_Rect es = { 0,0,1024,768 };
    bool quit = false;
    SDL_Event event;
    SDL_Renderer* renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
    int sX = 1, sY = 1;
    SDL_Texture* shp = IMG_LoadTexture(renderer, "K:\\spaceship.png");
    double sRot = 0.0;
    SDL_Rect SrcR,dest;
    SrcR.x = 0;
    SrcR.y = 0;
    SrcR.w = 600;
    SrcR.h = 600;

    dest.x = 300;
    dest.y = 300;
    dest.w = 60;
    dest.h = 60;

    double K = sRot * (M_PI / 180.0);
    int xA= dest.x, yA= dest.y;
    int rX, rY;
    while (!quit)
    {
        xA = dest.x + dest.w / 2;
        yA = dest.y + dest.h / 2;
        rX = dest.x;
        rY = dest.y;

        SDL_PollEvent(&event);

        switch (event.type)
        {
            case SDL_QUIT:
                quit = true;
                break;
            case SDL_KEYDOWN:
            {
                switch (event.key.keysym.sym)
                {
                    case SDLK_UP:
                    {
                        dest.y = dest.y - 1 * cos(K * -1);
                        dest.x = dest.x - 1 * sin(K * -1);
                        printf("x %d y %d %f\n", dest.x, dest.y,K*-1);
                    }break;
                    case SDLK_DOWN:
                    {
                        dest.y = dest.y + 1 * cos(K*-1);
                        dest.x = dest.x + 1 * sin(K*-1);
                        printf("x %d y %d %f\n", dest.x, dest.y, K*-1);
                    }break;
                    case SDLK_LEFT:
                    {
                        sRot = sRot - 1.0;
                        K = sRot / (180.0 / M_PI);
                        //printf("%lf\n",K );
                    }break;
                    case SDLK_RIGHT:
                    {
                        sRot = sRot + 1.0;
                        K = sRot / (180.0 / M_PI);
                        //printf("%lf\n", K );
                    }break;
                }
            }break;

        }
        SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);
        SDL_RenderFillRect(renderer, &es);
        SDL_Delay(10);
        SDL_RenderCopyEx(renderer, shp, &SrcR, &dest, sRot, NULL, SDL_FLIP_HORIZONTAL);
        SDL_SetRenderDrawColor(renderer, 255, 255, 255, SDL_ALPHA_OPAQUE);
        rotate_point(xA, yA, K, &rX,&rY);
        SDL_RenderDrawLine(renderer, xA/*dest.x + dest.w / 2*/,yA /*dest.y*/, xA - 100 * sin(K * -1), yA - 100 * cos(K * -1));
        SDL_SetRenderDrawColor(renderer, 255, 0, 0, SDL_ALPHA_OPAQUE);
        SDL_RenderDrawLine(renderer, rX,rY, rX - 100 * sin(K * -1), rY - 100 * cos(K * -1));
        SDL_RenderPresent(renderer);
    }

    // cleanup SDL

    SDL_DestroyRenderer(renderer);
    SDL_DestroyWindow(window);
    SDL_Quit();
    return 0;
}