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View Full Version : transparency map problem w/MR


Clondike7
01-02-2007, 09:37 PM
I'm working on an outdoor scene and I'm trying to do foliage with a few low-poly objects and transparency maps. Problem is Mental Ray for some reason renders out the whole poly model instead of just the textured parts with the opacity map. It works perfectly with Maya Software renderer but not with MR. I have tried PNGs, TIF, TGA and even separate .jpg opacity files. please help.

techmage
01-03-2007, 01:42 AM
Make sure the alpha channel on the file node is plugged to the shader properly.

Or you could use MR shaders. Plug a mib_lambert into a mib_continue, then plug the mib_continue into the shadingEngine material shader slot. Plug the file color into the mib_lambert diffuse and plug the alpha into the mib_continue transp.

Or if you use the mia_material it has a nice setting in it for cutout opacity, which is where you'd plug the alpha.

LehaS
01-03-2007, 07:48 PM
Well this a transparency network made solely via Mental Ray nodes... mib_color_alpha takes RGB values of texture and by premulitpying them with texture A value produces grayscale R,G,B,A , which all have the same value...

EDIT: Sorry forgot to add im using "tiff" texture with alpha channel included...

http://i34.photobucket.com/albums/d147/leha_sokol/network.jpg

Or you could use MR shaders. Plug a mib_lambert into a mib_continue, then plug the mib_continue into the shadingEngine material shader slot. Plug the file color into the mib_lambert diffuse and plug the alpha into the mib_continue transp.

hey rygoody

is there any reason why you use mib_continue instead of mib_transparency in your network?...they seem to do the same thing here...

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