everybody

I have tried achieving a good delta time and fps counter over the last few days, read and watched a lot about it, but still can't seem to get it to work.

Here is an example:

#include <iostream> #include <SDL.h> #include <SDL_image.h> int main(int argc, char* argv[]) { if (SDL_Init(SDL_INIT_VIDEO) != 0) { printf("error initializing SDL: %s\n", SDL_GetError()); } SDL_Window* window = SDL_CreateWindow("Title", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1000, 900, SDL_WINDOW_SHOWN); if (!window) { printf("error creating window: %s\n", SDL_GetError()); } Uint32 renderFlags = SDL_RENDERER_ACCELERATED; SDL_Renderer* renderer = SDL_CreateRenderer(window, -1, renderFlags); if (!renderer) { printf("error creating renderer"); SDL_DestroyWindow(window); SDL_Quit(); } SDL_Surface* surface = IMG_Load("dot.bmp"); if (!surface) { printf("Error creating surface: %s\n", SDL_GetError()); SDL_DestroyRenderer(renderer); SDL_DestroyWindow(window); SDL_Quit(); } SDL_Texture* texture = SDL_CreateTextureFromSurface(renderer, surface); SDL_FreeSurface(surface); if (!texture) { printf("error creating texture: %s\n", SDL_GetError()); SDL_DestroyRenderer(renderer); SDL_DestroyWindow(window); SDL_Quit(); } SDL_Rect dest; dest.x = 0; dest.y = 0; SDL_QueryTexture(texture, NULL, NULL, &dest.w, &dest.h); Uint64 NOW = SDL_GetPerformanceCounter(); Uint64 LAST = 0; double deltaTime = 0; while (true) { LAST = NOW; NOW = SDL_GetPerformanceCounter(); deltaTime = (double)((NOW - LAST) / (double)SDL_GetPerformanceFrequency()); SDL_RenderClear(renderer); dest.x += 50 * deltaTime; dest.y += 50 * deltaTime; SDL_RenderCopy(renderer, texture, NULL, &dest); SDL_RenderPresent(renderer); std::cout << "Delta Time: " << deltaTime << std::endl; std::cout << "FPS: " << 60.0 - deltaTime << std::endl; SDL_Delay(1000.0f / (60.0 - deltaTime)); } return 0; } 

I used the suggestion from this post: How to calculate delta time with SDL?

I print out "delta time" and "FPS" to the console and, while the deltaTime is slightly different each time, the FPS is stable 60 (which is the same value that I use in SDL_Delay to calculate delay in ms). But the test image is clearly moving not smoothly, it stutters and moves at inconsistent speed, and I can't understand why.

Please help me understand what I am doing wrong. I just can't understand it even after looking through many examples.