To deform a curve and keep it's length

[peliosis]

Hello,

I'm trying to write an operator which control the curve by rotating each point by some given angle (point attribute) around previous point.

After some testing I hit a problem because it doesn't keep segment lengths.

This is it:

P = 0;
for (i=0; i<Npt; i++)
	{
	if (ptnum >= i)
		{
		P += cossin;														   // WYSIWYG :)
		angle = ang*multip;												//multiplier parameter to experiment more freely
		cossin = normalize(set(cos(-angle), sin(-angle) ,0));  // normalize just to BE sure:)
		}
	}

It's just about the same as : P+=cossin;

What to do with it? Segment lengths change along with difference between angle attribute.

I suppose it does accumulate the cossin vectors, but looks like I'm flushed:( and don't quite get this SIMD thing.

[peliosis]

I attach a simple and superunflexible example of what is this all about.

How to create this in VEX ?

curveRotation_01.hipnc

[peliosis]

Now a python SOP that does exactly this.

How to achieve this in VEX?

The files are changed to new, solved versions.

pythonSopTest_02.hipnc

pt_curveDeformTest_02.otl

Edited April 30, 2009 by peliosis