6 replies to this topic

[jumper]

Hi,
I am rendering (with PBR) the extra image planes - "direct_shadow" and "indirect_shadow" and I am surprised that I could see that both of these shadow passes seem to have the diffuse textures of the material (on the objects) multiplied into them somehow.  It would be much better for our compositors if we had shadow passes that were not affected by the images applied to the diffuse textures. We need to isolate just the shadows themselves. I have attached a simple scene with a  PBR mantra rop. How can we render just the shadows? I could apply a white material to the objects and do a second render just for the shadows, but this would be a rather wasteful use of our limited resources.
Thanks!
Stephen Murphy

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[Erik_JE]

You can add a paramter to your mantra rop for disabling surface shading. Makes it really easy to do shadow passes.

EDIT: Guess that was not much of an answer but it's a way of kinda solving the issue without the hassle of switching materials etc on all objects.

Edited by Erik_JE, 19 March 2012 - 05:15 AM.

[jumper]

Forgot to mention I am using 12.0.565
Thanks!
s

[eetu]

Might be a long shot, but there is an entry in the journal that just might be relevant:

Quote

Houdini 12.0.566: Correct a double-computation of light exports when rendering with PBR that would lead to incorrect deep raster planes and slow rendering.

[dyei nightmare]

i noticed this too, but i dont think that is a problem, all depends in your other difuse passes, which are generally lacking of that darker shade

Edited by dyei nightmare, 19 March 2012 - 06:55 AM.

[dyei nightmare]

BTW... you could use the forced phantom, forced mate, candidate objects and lights settings in the mantra node... or i am missing something?

Edited by dyei nightmare, 19 March 2012 - 07:27 AM.

[jumper]

Thanks for the help. I was trying to only render the scene once and use the above passes  - if you turn off the spec on the material seems to work!(?)
s