float dot_to_alpha(float dot)
{
float f = 1.0f - MathUtil.WyvillFalloff(dot, AlphaCutoff, 1.0f);
//float f = MathUtil.WyvillRise01(dot);
//if (f < AlphaCutoff) f = 0;
return(MathUtil.Clamp(f, 0.0f, 1.0f));
}
