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StefanAlbertz
05-16-2007, 11:04 AM
How can i get MR Geometry Shaders to work in Maya? I connected a simple cone MR Geometry Shader to the transform nodeīs Mental Ray Geometry Shader Attribute. Rendering the scene shows the cone in the alpha channel, but the color channel for the cone surface area is black (it occludes other geometry behind it, so i guess it doesnt get the illumination?)

Any help welcome :) thanks in advance

AtrusDni
05-16-2007, 06:46 PM
Geometry shaders are kind of an incomplete feature with mental ray for maya. Mental Ray standalone works fine. Dont know if they fixed this in Maya 8 or not . . . Good luck with that.

StefanAlbertz
05-21-2007, 03:11 PM
no quite the answer i wanted to hear .. but thanks ;)

final render will beat mental ray in the implentation run once again for sure ... thatīs a pitty. is it that hard to implement already working functionality? .. *sight*

floze
05-21-2007, 05:57 PM
no quite the answer i wanted to hear .. but thanks ;)

final render will beat mental ray in the implentation run once again for sure ... thatīs a pitty. is it that hard to implement already working functionality? .. *sight*
It's actually working, not sure what went wrong with your test.

There was a bug with the connection, when the geometry shader has been created directly from within the transform node. Worked when manually connecting it though, and it should be fixed with 8.5 afaik.

techmage
05-22-2007, 12:09 AM
the thing I wanna know is, how do I use this geometry shader to instance\proxy trees

Is that possible to do yet?

Hans-CC
05-22-2007, 03:11 AM
hi floze , im also interested in this , do you think that is posible to make high res objects in maya export them as .mi and then just use for instance "boxes" in the viewport wile mental ray renders the real objects ?

thanks

Hans

floze
05-22-2007, 10:19 AM
hi floze , im also interested in this , do you think that is posible to make high res objects in maya export them as .mi and then just use for instance "boxes" in the viewport wile mental ray renders the real objects ?

thanks

Hans
According to Francesca, reading in .mi files is not possible with mayatomr. Though you could write your own parser to load them:

but ... when you'll have resolved what you think is the sintax error you'll find
the real error. and it is still a sintax error. :) and it is that, - the word 'incremental'
is not parsed correctly by the raylib. ie it is commercially limited. you can't source
objects in that way from any dcc application. apart if you write your own parser has
we did. MI could at least document that. long life to MI_API_OBJECT_FILE. :)

It's sad no one ever publicly released such a tool.

Matadŏr
05-22-2007, 11:49 AM
Thanks floze for all your continuous support on this forums.
This is a matter of great importance for many people, a real shame that mayatomr doesn't provide one of the more interesting possibilities of MR. If only someone released a good functional solution for this problem (replacing of geometry at MR render time) i am sure many people would think in buying it. I mean, there are many small studios (in visualization at least) that can't have the means (programmers) to make the tools but maybe are willing to pay for the final developed releases.

I hope :)

PS - i noticed francesca disappeared on the forums, i hope everything is ok with her.

StefanAlbertz
05-22-2007, 01:52 PM
as i said before, if thats not working with mr itīs a shame, since "smaller" renderers start to implement this feature now and we know that itīs already inside the mental ray feature set. Iīve tested final render in alpha and beta and rib-boxes (in renderman, close to geo_instance in mr) are one of the upcoming features where a slim locator can carry a whole scene .. would be the poor-manīs-solution for creating high-polycount scenes.

so.. other question: when using mental ray standalone, can we use the maya shader mib_geo_instance to do the referencing? or is there no easy way to use that feature?

floze
05-22-2007, 02:12 PM
as i said before, if thats not working with mr itīs a shame, since "smaller" renderers start to implement this feature now and we know that itīs already inside the mental ray feature set. Iīve tested final render in alpha and beta and rib-boxes (in renderman, close to geo_instance in mr) are one of the upcoming features where a slim locator can carry a whole scene .. would be the poor-manīs-solution for creating high-polycount scenes.

so.. other question: when using mental ray standalone, can we use the maya shader mib_geo_instance to do the referencing? or is there no easy way to use that feature?
Of course it does work with mental ray standalone:

http://www.lamrug.org/resources/placeholdertips.html

It's only a limitation of the mayatomr translator.

StefanAlbertz
05-22-2007, 03:02 PM
Thanks Florian! greets to philip

slipknot66
05-22-2007, 03:38 PM
I remember max from ctrl_studio, wrote a shader called ctrl_objects, the could be used to create proxies with geometry shaders in MR. Not sure if its still available to download.

Hans-CC
05-22-2007, 07:02 PM
I remember max from ctrl_studio, wrote a shader called ctrl_objects, the could be used to create proxies with geometry shaders in MR. Not sure if its still available to download.

its is a shame it does't work with mayatomr , this could be a highly usefull feature !!!
if anyone know how to get ctrl_objects or something similiar please tell us.

edit: since i don have stand alone , dont now if this is posible nor can't i try it ,but do you think its posible to export an mi from max or xsi (using only mr shaders obiosly!!) and used it in a maya scene ?


thanks
Hans

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