Cannot see vertex colors in realtime shaders ogl view mode

Symptom

My scene includes objects with <I>RealTime shaders</I> and <I>vertex color maps</I>. When I switch the camera viewport to <I>RealTime Shaders</I> view mode, I do not see the <I>vertex colors</I> associated with my scene objects. What needs to be done?

Solution

Follow these simple steps to fix the issue :

1. Load the following <I>RealTime Shaders</I> in the Renter tree : <I>R.T-Nodes-RealTime</I>-<I>OGLDraw</I>, <I>OGLShade</I>, and <I>OGLCombined.</I>
2. Proceed with the following shader tree connections <I>: OGLCombined </I>into the<I> OGLShade-Previous </I>input; <I>OGLShade</I> into the <I>OGLDraw-Previous</I> input; and lastly OGLDraw into the Material-Realtime input.
3. Open the <I>OGLDraw</I> PPG (double-click on the shader tree node), and make these modifications : enable the <I>OGLDraw-Blending</I> parameter; change the <I>Source</I> parameter to <I>ONE</I> and the <I>Destination</I> paramter to <I>SRC_COLOR</I>; and most importantly, disable the <I>OGLShade-Enable Lighting</I> parameter to eliminate the influence of the scene lights.

Result : Now, the vertex colors will appear as a constant color map on the objects when viewed in <I>RealTime Shaders</I> OGL viewing mode. You can experiment with the various <I>OGLDraw Source </I>and<I> Destination </I>options, according to your scene specifications and needs, and paint new vertex colors on the objects without any problems.

Example

References

Sources</B>

Gareth Morgan, <I>Program Manager – Games</I>, at Softimage

Prepared by :
Pierre Duranleau, <I>3D Graphics Support – Escalation</I>, at Softimage.

All about RealTime Shaders

Softimage XSI – Lights, Shaders, & Cameras</I> : chp 11, page 247.