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awells
01-27-2009, 12:38 AM
Hey All,

I’m having the following problem when attempting to run a simulation based on the one described in this (http://area.autodesk.com/index.php/blogs_duncan/blog_detail/water_using_ncloth_part_1_of_2/) tutorial: When the particle shape’s bounding box intersects my ground plane the intersecting area shows up in the render. I’ve stripped down my scene to a point where it’s identical to nClothWater2.ma (which can be found at the bottom of the tutorial page) except with an mib_amb_occlusion node connected to the ground plane’s shader (mib_amb_occlusion.outValue -> lambert.transparency). I’m also rendering with my primary renderer set to “Rasterizer” in the mental ray globals, but scanline and raytracing give the same result. Any ideas?

Thnx,
Alex
awells
01-30-2009, 12:30 AM
For those who are interested in the solution..

You can keep an object from occluding a surface by giving the connected mib_amb_occlusion node a inclexcl id of -1 and the offending object an miLabel set to 1. That way the ambient occlusion node doesn't consider the offending object.. Or something like that.

There's a much better explanation here (http://www.djx.com.au/blog/2007/05/12/ambient-occlusion-with-milabel/).
And a related thread here (http://forums.cgsociety.org/showthread.php?t=270669).
awells
01-30-2009, 12:33 AM
A related question..

Is it possible to do the something similar with a particle bounding box and an envCube node? I'm having basically the same issue as above, except this time the particleShape's bounding box is occluding the reflection from an envCube. Any ideas?



@admins: If possible, can we have this thread moved to the Maya Rendering forum? thnx.
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