Projection Tutorial in RenderMan for Maya

This tutorial covers how to setup projections in RenderMan for Maya. I put this together in response to a question I received after posting a lecture on Pattern Generation at Pixar (https://youtu.be/vYi_Dh8ROSg or https://community.renderman.pixar.com/article/1862/pattern-generation-at-pixar.html), regarding the slide on how shading TDs use custom coordinate systems to project detail on more general shaders. There are many ways to do this, but in this tutorial I work with RenderMan for Maya, and show how to use place3dTexture nodes as coordinate systems. These are then used in PxrManifold3D nodes that feed PxrProjection Layer nodes, that are then composited together in a PxrProjectionStack node. At some point I hope to show the equivalent workflow in RenderMan for Katana. A few notes about this demo: 1) This is a free model from high-end 3d 2) The starting shader uses a RoundedCube map to project a brick texture. Dirt is layered on , with opacity driven by occlusion, curvature, facing ratio to world up, and a fractal. To see how this is setup, check out part one of my terrain shading tutorial: https://youtu.be/gy8URR1ypik or https://community.renderman.pixar.com/article/1863/procedural-terrain-shading-and-xgen-demo.html 3) The occlusion and curvature nodes (PxrDirt), are all baked to ensure good performance. To see how to do this, check out part two of my terrain shading tutorial: https://youtu.be/kQgNSAdtiFo or https://community.renderman.pixar.com/article/1863/procedural-terrain-shading-and-xgen-demo.html 4) This demo is running on a windows partition on a 2015 macbook pro. Performance is "okay", but screen recording and some windows update processes were contending for threads.