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View Full Version : can someone esplain me what's wrong with my shadow passes?


cgbeige
06-23-2009, 02:22 PM
I don't use render passes usually since I don't do animation but I need them for this project. My problem is that I'm trying to get this scene at the left to render shadow passes and I have both Shadow and Raw Shadow options set in the pass options and mia_material_x_passes used for MOST of the shaders, most importantly just being the earth part which is to be comped in Photoshop. As you can see, it's just spitting out garbage from what I can tell. Do I need to have mia_material_x_passes for all shaders in the scene for it to work or is something else going on here?

cgbeige
06-23-2009, 05:01 PM
ok - MR is officially a steaming turd. After jiggling many handles and learning that shadow passes are meant to be set to difference mode, this is the closest I got to getting a usable result:

http://www.3eige.com/ars/%5Bimg%5Dfile:///Users/beige/Library/Caches/TemporaryItems/moz-screenshot.pnghttp://www.3eige.com/ars/renderpassproblem.jpg

The irony: using NO mia_material_x_passes seemed to work. But the render buffer is set to 32-bit but all the passes render as 8-bit and, get this, the Master Beauty pass (the beautiful garbled mess above) is 16-bit. EXR files turn out completely black. HOW IS THIS SOFTWARE NOT ALPHA?

every time I have to use Mental Ray, it's like setting a match to my day.

cgbeige
06-23-2009, 05:12 PM
ok - upon further inspection, it seems that my shadow passes are not including all shadows. I just want a simple image that shows all the shadows. Is this possible?

cgbeige
06-24-2009, 04:03 PM
wow - so MR really is broken? As little control as there is in Maxwell for compositing, I can at least get a shadow pass to work.

bezzeler2000
06-24-2009, 05:09 PM
You will need mia_x_passes shaders for all the geo that deal with the shadow. Meaning from the object down to the geo that the shadow is being cast onto. What are you getting when you don't render in shadows?

davegreenwood
06-24-2009, 06:11 PM
Hi, you might find it easier to use the maya mats (blinn, lambert, etc. ) to set up your render passes, they all work as you would expect. Make sure you batch render, not preview render, and bear in mind the photoshop plug turns alpha into transparency. Here's a simple scene with one light, a sphere and a plane.

cgbeige
06-24-2009, 06:22 PM
thanks dave.

bezzeler2000 - can you actually confirm that shadow passes work for you? everything I'm seeing around is that other people are having similar problems

MasonDoran
06-26-2009, 11:02 AM
shadow pass works fine,

Things get messed up though if you mix Maya shaders with MR shaders.
The pass system is not fully integrated yet, so if you mix the 2 kinds of shaders, your passes will not give the proper results.

cgbeige
06-26-2009, 03:26 PM
shadow pass works fine,

Things get messed up though if you mix Maya shaders with MR shaders.
The pass system is not fully integrated yet, so if you mix the 2 kinds of shaders, your passes will not give the proper results.

Prove me wrong by taking the file posted above and changing the two shaders to mia_material_x_passes and getting it to work. It renders fine with the lambert and phong but the mia pass mats don't work

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06-26-2009, 03:26 PM
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