[Closed] Bias in Twist modifier

Point3 TwistDeformer::Map(int i, Point3 p)
   {
   float x, y, z, cosine, sine, a;
   if (theAngle==0.0f) return p;
   p = p * tm;

   x = p.x;
   y = p.y;
   
   if (doRegion) {
      if (p.z<from) {
         z = from;
      } else 
      if (p.z>to) {
         z = to;
      } else {
         z = p.z;
         }
   } else { 
      z = p.z;
      }  
   
   if (doBias) {
      float u = z/height;
      a = theAngle * (float)pow(fabs(u), bias);
      if (u<0.0) a = -a;
   } else {
      a = z * angleOverHeight;
      }
   cosine = float(cos(a));
   sine = float(sin(a));
   p.x =  cosine*x + sine*y;
   p.y = -sine*x + cosine*y;

   p = p * invtm;
   return p;
   }

when positive it moves the bias up (ie more twist at the end) when negative it bias’s the start (ie more twist at the start) kind of an ease in ease out kind of thang

it sometimes looks like it cancels it out @ ± 100 as the twist is “squeezed” into a zero range so has no net effect.