More and more, I am using Pixel Cloud as a visualization tool. Although, I may not have the need to relight a 3D render, I am compositing it with another pass or a background. In order to make sure the composite works, it helps to visualize how it may look within a 3D space. Pixel Cloud can help with that. Last night, I was experimenting with outputting a PPass and a Normal Pass as a UV texture from within Maya. Using this technique, you can create a point cloud not just from the view of the camera, but from all textured points on the model. Maya’s Batch Bake function allows you to do this, with it’s support for baking 32-bit texture maps. Although you cannot create image sequences in this way, you can create a working reference of the CG model from all angles. This reference could be useful when visualizing a composite.

The application of this technique is quite simple. Create and texture your position pass as normal and use Batch Bake t0 create 32-bit floating point tiffs for each pass. You need to make sure that UVs are completely unfolded and not flipped, otherwise the command may not work. Also set your options to output 32-bit. Import into After Effects and use these passes with Pixel Cloud as you normally would.

Creating the PPass texture in Maya will be the same as connecting the samplerInfo node’s pointWorld with the outColor of a surface shader. Creating the Normal Pass is a little different. One needs to connect the samplerInfo’s normalCamera to a vector product node. Then connect the rendering camera’s worldMatrix to the vector product node. Set the vector product node to matrix multiply and connect the output to the outColor of the surface shader. You can then use Batch Bake to create the texture map/passes. These were my settings.
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