Carve Sop?

[B.J]

Hi all,

does anyone know how to drive the v value of a carve SOP with a points posistion?

I have a curve which I've swept a circle on. I now need to carve it as a leading edge with a point which is animated.

Thanks in advance.

B.J

[SpencerL]

you can just use the point( ) expression.

point("../add1", 0, "P", 1)

This example is using the $TY position of point "0" of the "add SOP" to drive the V value of the carve SOP.

[B.J]

you can just use the point( ) expression.

point("../add1", 0, "P", 1)

This example is using the $TY position of point "0" of the "add SOP" to drive the V value of the carve SOP.

That gives me no result but when I use

point("../add1", 0, "P", 0)

it animates but with a delay to start with, then faster than the point, then it goes backwards....Er?

Any ideas?

Thanks

[SpencerL]

It works fine for me when I move the point in the Y direction, so not sure whats going on there...Also, since the carve value ranges between 0 and 1, I would assume that your point position starts with a negative value before it gets to 0. That is probably what is causing the delay at the beginning and the reason for why it goes backwards...I think it would just depend on what your animation is doing. A way to try and fix this is to normalize your point position using either the normalize( ) expression, or a simple VOP SOP that normalizes your Position. Can we see your scene file?

[FrankFirsching]

Perhaps I've misunderstood your question, but I think you should use the pointdist and unituv functions. I've attached an example to clarify it. The pointdist functions computes the parametric value of the nearest point on the curve and the unituv function converts the parametric value to the [0;1] range needed by the carve sop.

The example file is copying a cube to the position of the point, that drives the carving just to visualize the process.

carveExample.hipnc