XM Magdalena 3D print, GGeorgy (3D)
LC #42 Pipers Alley

View Full Version : Mental Ray- Problem keying visibility

03-14-2006, 03:06 PM
Hi, I am trying to key the vsibility on some objects on and off and then render it. . It works fine in the playplast and frame render but when I mental ray batch it, it doesn't work right. It seems that nothing that is already on screen at frame 1 can dissappear, and nothing that appears after frame 1 has a texture. Is there a way to tell mental ray to think about these things on every frame?

Playblast (http://s133404583.onlinehome.us/temp/cdcase5pbLg_Prog.mov)

Batch Render (http://s133404583.onlinehome.us/temp/cdtest5Lg_Prog.mov)

Thanks for any advice!

03-14-2006, 03:39 PM
ok, I found this thread (http://forums.cgsociety.org/showthread.php?t=255706), which suggests turning off "Optimize non-animated display visibility" but that seems to just make everything visible no matter what.. I will continue to experiment..

03-14-2006, 07:18 PM
hi again, here is the answer. I found it buried in this thread (http://forums.cgsociety.org/showthread.php?t=200334).

the settings that work for me, are to
key the "mi visibility" rather than the regular visibility.
Then to set the mental ray render settings, under

turn off optimize non-animated visibility,
turn off optimize animation detection

Then, each shape node has a checkbox-
Mental Ray-> Flags-> Derive from Maya
You must uncheck this for each object with keyed visibility.

In fact, I had done a bunch of set driven keys to animate the visibility, and was able to simply link those animation curve output nodes to the mivisibility attribute also. (they were already linked to the regular visibility attribute) This allows me to have it work both in the working view and in the batch render. Hope this helps some people out.

03-15-2006, 02:22 AM
sweet, thanks...

03-22-2006, 06:24 PM
one obnoxious caveat- if you have invisible obejcts that happen to intersect with visible objects, the invisibles' textures may get projected onto the visible geometry.

03-28-2006, 05:09 PM
I believe it is also necessary, if the keyed visibility is visible in reflections, to also key the miTrace function in.

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03-28-2006, 05:09 PM
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