Bias and Gain

An interactive demonstration of Ken Perlin's bias and gain functions. Implemented using Christophe Schlick's fast bias alternative function (as found in game programming gems 2). More information at my blog here: Bias And Gain Are Your Friend

Function: Parameter: 0.5
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Functions (in Javascript)

function GetBias(time,bias)
{
  return (time / ((((1.0/bias) - 2.0)*(1.0 - time))+1.0));
}

function GetGain(time,gain)
{
  if(time < 0.5)
    return GetBias(time * 2.0,gain)/2.0;
  else
    return GetBias(time * 2.0 - 1.0,1.0 - gain)/2.0 + 0.5;
}