Pulls input curves towards guide curves.
Each curve in the Input Curves is drawn towards the nearest curve
in the Guide Curves.
The Convergence Root and Convergence Tip specify how much
each curve is pulled towards the nearest guide curve, from the start of the curve to its end,
on a unit scale from zero to one.
The Convergence Gamma adjusts the ramped interpolation from base to tip.
A gamma below one will draw toward tip convergence earlier along the curve,
while a gamma above one will wait longer to move towards tip convergence.
tested in Houdini
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