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View Full Version : Ray Cast Geometry Node to create forcefield effects - Is this possible?



Firestar3D
04-07-2014, 03:46 AM
Hi all,

I'm currently giving LW 11.6 a try, and wanted to know if it's possible to use Ray Cast Geometry to affect a surface on another object.

Specifically, I am looking to create a texture value based upon geometry that is intersecting with the surface in question. I remember once seeing a tutorial on the subject (not using Ray Cast Geometry, and for an older version of LW) but it has since disappeared.

So far, my brief experiments have yielded unsatisfactory results. I am able to have the node obtain ray casting data for when an object is in front of it, or behind, but not intersecting.

It might help if there was documentation on what the "Hit Normal" and "Intersect" vector outputs on the node do, and whether the information can be used to detect if a given object is in contact with the surface.

I have to think this is possible; after all, the demonstration videos include the example of an egg object passing through a tube, but translating this into information that can be used on a surface is what I am finding elusive.

Then again, math has never been my strongest suit, so maybe I am missing something obvious?

Cheers,

RebelHill
04-08-2014, 06:49 AM
Use the distance output. This tell you how far from the ray source the hit point is.

For the vector outputs... you may find it helpful to get a review of how to use and understand vectors in nodal... https://www.youtube.com/watch?v=zZYxAF0yJyU&list=PL1C4072533A16B807&index=9