Question

This is in C++ and I’m using VC++ 2010.

I am creating a tile-based game, each tile is 32 pixels. If you are given an amount of time, and in that time you want to move an image 32 pixels in a direction, how would I calculate the amount to move per each frame? The frame rate is not fixed and I have access to the frame delta time.

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Answer 1

The basic formula you need to calculate it is:

P pixels / S seconds * delta T seconds/frame = X pixels/frame

For example we’ll use your tile size and move it in 1 second and the current frame rate is 30 fps.

32 pixels / 1 second * .033 seconds/frame = 1.056 pixels/frame

int P = 32;
double S = 1.0;
double T = getFrameTime();
double X = P / S * T;