Chris Colefax wrote:
> 
> As Kevin pointed out, what you've divided is the rotation angle, so every
> second point will be *rotated* half as much as it should be (still at the
> same radius), rather than scaled.  Also, the switch you've used is not
> necessary, as you can actually use a counter variable that increments in
> steps other than 1, eg:
> 
> #macro star_prism (Sides, StarFactor, Height1, Height2)
>   #local RotAngle = 360/Sides;
>   prism {linear_sweep linear_spline Height1, Height2, Sides+1, x,
>     #local Count = 0.5; #while (Count < Sides)
>       vrotate (x/StarFactor, y*RotAngle*Count),
>     #local Count = Count + 0.5;
>       vrotate (x, y*RotAngle*Count),
>     #local Count = Count + 0.5; #end
>     x}
> #end
	Actually, you could even use directly  the angle as a counter, which
should be faster (no multiplication):

#macro star_prism (Sides, StarFactor, Height1, Height2)
  #local RotAngle = 180/Sides;
  #local EndAngle = 360-RotAngle/2; // to avoid rounding problems
  prism {
    linear_sweep linear_spline Height1, Height2, Sides+1, x,
    #local Angle = 0;
    #while (Angle < EndAngle)
      vrotate (<1/StarFactor, 0, 0>, <0, Angle, 0>),
      #local Angle = Angle + RotAngle;
      vrotate (x, <0, Angle, 0>),
      #local Count = Angle + RotAngle;
    #end
    x
  }
#end

		Jerome

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