View Full Version : rendering layer with alternate reflection?

01 January 2009, 05:59 PM
Hi everyone, another question from a greatful novice... :)

This is kind of confusing but hopefully I can explain it clearly.

I have a scene with moving objects and moving lights, that also has a mirror (using a phong shader) in it. I want to render the scene, but have the geometry that is reflected in the mirror to have different textures in the reflection. so for example, a checkered yellow sphere will pass by the mirror and look like a blue sphere in the mirror reflection.

So far the only idea i have is to render the animation twice, once normal. and then to change the textures/shaders/lights and render it again, and them compositing the 2 layers with a mask.

But is there a better way to do this? i am guessing setting up some kind of render layers might help? maybe one just for the reflection? one thing I am concerned about if I just mask it out like i am thinking is when objects move infront of the mirror, do i need to composit with depth information??

Any pointers would be really apprecaited! Thank you anyone who is willing to help!
- Kat :love:

01 January 2009, 09:40 AM
just put the mirror and lights on a renderlayer, add the sphere to it. after that turn off all the options
in the render stats section of the shapenode except of "visible in reflections" (with an override). make a material override on the sphere and add the shader with the look you want. now you should
have a pass with only the mirror and the object in the reflection and you can compose it
over the other passes. (you need to add black surface shaders to objects which block the
mirror, if needed)
hope that helps :o)


01 January 2009, 07:11 PM
Thank you so much, Borgus!

This is working out great!
The only question I have now is that the spheres themselves sometimes pass in front of the mirror... So if I add a black shader to them they will show up as black in the mirror... any ideas? Can I use the depth channel in the compositing somehow?
thanks again!! :love:

01 January 2009, 10:13 PM
hi kvalenti!
don't know exactly what you mean but did you try to turn "visible in reflections" off in the


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