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Vex - Generate @Cd threw intersecting with a mesh

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Christoph_H_
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Hello,
how is it possible to generate @Cd threw intersecting with a mesh?
In the area from the second mesh should be colord points or primitives on the first mesh.

thanks.

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example.JPG (87.5 KB)

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BabaJ
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Keep your eyes peeled for others methods you may like better.

More than one way to do it.

Attachments:
Cd via Bounds.hiplc (69.9 KB)

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Aizatulin
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Hi,

“intersect_all” can help you aswell. If you count the number of intersections of a ray in any direction, it should be odd inside and even outside. But sometimes I've ran into numerical problems, if the intersection points are close together. You can minimize this problem by decreasing the tolerance.

Attachments:
InteriorColor.hipnc (74.4 KB)

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Christoph_H_
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Thank you both very much.
Very instructive.
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Aizatulin
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Sure man ,

I just found out, that the ray length has not been calculated correctly, so I've attached a fixed version.

Attachments:
InteriorColorfixed.hipnc (75.7 KB)

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Nicolas Longchamps
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Volumes would be great for this. It might be more efficient as you can control the sampling of the incoming geo and it should scale really well with geometric complexity.



Simply use a volume sample in a point VOP on the object you want colors on. Pipe in the volume and sample it at the point position.
Edited by Nicolas Longchamps - 2018年5月16日 16:26:18

Attachments:
IntersectVolumeSample.png (1.4 MB)

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