Smooth damp or tween algorithm

Question

I would like to know an algorithm for smooth damp or as some people call it, tween. I would like it in Lua preferably but anything will help.

I have tried watching unity

Answer 1

If I understand the question correctly, you're looking for an easing function. There is a Lua library that provides a set of easing functions on GitHub: https://github.com/EmmanuelOga/easing

An example would be:

local function inOutQuad(t, b, c, d)
  t = t / d * 2
  if t < 1 then
    return c / 2 * pow(t, 2) + b
  else
    return -c / 2 * ((t - 1) * (t - 3) - 1) + b
  end
end

Where t = time, b = begin value, c = change in value, and d = duration.

More information on these easing functions is available directly from Robert Penner here (this is where the function above is derived from): http://www.robertpenner.com/easing/