View Full Version : Use Background Shader visible in Reflections?

06 June 2009, 12:29 PM
Hello CG Talkers.

I am new to Maya, working on my first animation project and now I came to the render part.
I am using the "Use Background Shader" for my ground plane to create an infinite white world, but still being able to receive shadows on that plane.

Everything works fine except that when I put in a reflective object it reflects the ground plane as if it had a regular shader and not the "Use Background Shader". That means the horizon is still visible in the reflection while it is invisible in general. I have attached a screen shot in case it is not quite clear. The rainbow should be reflective in this case, but it should only reflect the shadows on the ground plane not the geometry of the ground plane itself (which it quite clearly does as you can see by the reflected horizon line).

The only solution I came up with was to turn off "Visible in Reflections" in the planes Render Stats tab, but that unfortunately also gets rid of the shadows in the reflections and I would like to keep those.

Is there a way to work around this? So still have a reflection of the shadows, but not of the plane itself.

Thank you in advance,


Edit: Sorry, forgot to mention. I am rendering with mentalray and using Final Gathering, if that's important.

08 August 2009, 07:13 AM
Select your ground plane. Open the Attribute Editor. Open the Shape node. Under Render Stats uncheck Visible in reflections.

Cancel the above. I'm sorry, I didn't read your post carefully enough.

08 August 2009, 12:08 PM
the background shader can be flakey...Id avoid it if possible.

What Id do is make a shadow pass render layer. Give your floor a white lambert shader, select all your objects in the scene (whilst having the shadow render layer selected) and turn off the primary visibility in the attribute spreadsheet. When you render out your beauty or whatever, and then your floor shadow, you can just make a grad or flat colour backgound in your compositing package, and multiply the shadow onto that, giving you your infinity cove effect.

08 August 2009, 01:23 PM
Adjust the 【Attributeuse】of【Background Reflectivity】to 0,done.

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08 August 2009, 01:23 PM
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