Spline demo - All OPENSCAD

module spline
Simple list of points is turned to soft spline passing through all points
point formats
[x,y,z] or [x,y,z,scale] or [x,y,z,[xscale,yscale,zscale]]
or [x,y,z,scale/[xscale,yscale,zscale],[r,g,b]]
Children
If spline has zero children a stand in sphere(1) will be appointed.
for children Z+ is the sweeping direction.

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Now the powerful part is to do things your self
format of points can be extended by any dimension or anything t