Hoping to get Contours to appear in reflections

[prodeguerriero]

Hello everyone,

this is my first time on this forum. If I'm lucky enough some guru will be able to help me out here because I've been searching all over the place for a solution (and asked my teachers here at SCAD too) and found none.

The matter is pretty straightforward. I have a little statue built with multiple cubes, so not a single mesh, and I got contours on it by using the settings built in maya (render features and shading group). My problem arises when the statue moves in front of reflective objects which reflect back the statue without the contours.

I think there might be a way to fix this using one of the many contour shaders that come with mentalRay, but I have no clue on how to use them.

Any help would be really appreciated!

Cheers,

Gabe

[Remydrh]

I am not sure if the Maya built-in contours have this, but the custom contour shaders will draw contours on a reflection or refraction using the depth limit parameters (min_level and max_level)

http://docs.autodesk.com/MENTALRAY/2...unction_levels

Building this manually can be a bit complicated. I might be able to post a simple scene later with the basic setup. What version of Maya are you using?

[Remydrh]

Hmm having sort of a problem, been awhile since I've done this, Maya 2012 tells me:

while defining camera "perspShape": undefined shader "contour_composite1"

[prodeguerriero]

Building this manually can be a bit complicated. I might be able to post a simple scene later with the basic setup. What version of Maya are you using?

I am using maya 2012, both at home and at school

I had already found out about those two parameters, but I can't find them in the built-in functions and I have no clue on how to set up the shaders altogether. Can you point me to some documentation/tutorial in using the mentalRay shaders. I have a vague idea because I know how to use the lens shaders, like the bokeh, but that is pretty much it.

Thanks a lot for the help!

Gabe

[steve]

... I got contours on it by using the settings built in maya (render features and shading group). My problem arises when the statue moves in front of reflective objects which reflect back the statue without the contours.

First of all, the contours rendered by mental ray are 2D lines drawn in post. This means, they are not like 3D objects which can be reflected or refracted. However, contours may be detected and generated for objects seen in reflections or refractions. This is a little more expensive to compute, in general.

The Maya builtin contour shaders for mental ray do not support contours around secondary effects like reflection or refraction. But the custom contour shaders delivered with Maya allow you to achieve that, although the user interface for those nodes is a bit more basic.

As an example, this is how the builtin contour shaders would render:

contour_reflection.png

This is what you can get with the custom contour shaders. Note, the different look of the contours on the reflected object compared to its original.

contour_reflection_custom.png

To achieve this, goto the Custom Shaders section of the contour settings, and attach two new shaders contour_store_function and contour_contrast_function_levels as shown below.

Maya Contour Custom Shaders.png

In the AE of the contour contrast shader you can raise the max level parameter to get contours for secondary, or even higher trace depth effects.

Maya AE Contour Function Levels.png


Hope this helps. Best, Steve.

[prodeguerriero]

Thanks a lot. I already did figure out some of this stuff, but I am still having a little issue with it. I'm going to take a couple of screen captures during the week end and show it to you.

Thanks again!

[Remydrh]

The output shader for this crashes for me constantly. Curious if this was introduced awhile back and no one noticed.

Steffen, is the output shader necessary? Not sure how you managed to get those to render.

[thorsten hartmann]

Hi

we use in 3dsmax the XSI-toon Shader, look here: http://forums.cgsociety.org/showthread.php?t=767636

[juri]

Are you using Maya passes? There has been a recent fix (not out yet) which could be related.

Juri

[Remydrh]

Me? The crash?

I wasn't using passes.

while defining camera "perspShape": undefined shader "contour_composite1"

*crash*