Using my loop based on this: https://gafferongames.com/post/fix_your_timestep/
Trying to get my game to run at fixed 60FPS (both update and render) for all machines. Studied the link above and have been stuck on this game loop for weeks trying to get it to work smoothly to glide this image across the screen. I had dealt constantly with jittering and possible tearing. I can't recall what I did to fix it exactly, but I believe it may have something to do with not rounding a variable properly (such as delta).
So yeah, currently the loop works but I'm afraid as I develop the game more and have to render more, eventually something I'm doing in my loop could cause slowdowns or larger CPU usage. Does the structure of the game loop below seem okay or is there something I can do to optimize it?
The 2D game is a generic sidescroller. Not too heavy on physics, mainly just simple platformer physics. I feel as though I'm using way too much CPU.
void Game::mainLoop() {
double fps = 60.0f;
int frameSkip = 5;
int deltaSkip = frameSkip;
double miliPerFrame = 1000.0 / fps;
double xx = 0.0f;
double playSpeed = 5;
Uint64 previous = SDL_GetPerformanceCounter();
double accumulator = 0.0f;
bool shouldRender = false;
bool running = true;
while(running){
Uint64 current = SDL_GetPerformanceCounter();
double elapsed = (current-previous) * 1000;
elapsed = (double) (elapsed / SDL_GetPerformanceFrequency() );
previous = current;
// handleEvents()
handleEvents();
// when we press escape reset x to 0 to keep testing
// when he goes off screen
if(key_states[SDL_SCANCODE_ESCAPE]) xx = 0;
accumulator+=elapsed;
if(accumulator >= miliPerFrame * frameSkip) accumulator = 0;
shouldRender = accumulator >= miliPerFrame;
while(accumulator >= miliPerFrame){
// update()
//cout << playSpeed << endl;
double delta = ceil(elapsed);
if(delta > deltaSkip) delta = 1;
//if(elapsed >= 1) delta = elapsed;
xx+= playSpeed * delta;// * (1 / fps);
// /update()
accumulator -= miliPerFrame; //get what's left over
}
if(shouldRender){
// render()
SDL_SetRenderDrawColor(gameRenderer, 0xFF, 0xFF, 0xFF, 0xFF);
SDL_RenderClear(gameRenderer);
imageController.drawImage("colorkeytest", floor(xx), 0);
SDL_RenderPresent(gameRenderer);
// /render()
}
}
}
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