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• Fixed a bug where file textures from material x networks would appear vertically flipped in RenderMan renders. The old behavior can be restored via the env var HD_PRMAN_MATERIALX_VERTICAL_FLIP=false

• Bail if we see a "multioutput" connection, since these aren't supported yet (Note, studio has added support, but involves a USD change that we're not using yet)

• Fixed an issue for mtlx image files where the rtx plug-in gets referenced. The heuristic for grabbing the texture node ptr was sometimes failing.

• Fixed an issue for tex files: resolve the path, because RenderMan doesn't know about usd file relative paths.

• For mtlx image file nodes without a texcoord connection automatically wire in a mtlx geompropvalue specifying st texture coords

• Fixed a bug where toggling visibility of individual instances would lead to a crash.

• Added support for PRMAN_OSL_BEFORE_RIXPLUGINS environment variable when running the RenderMan hydra delegate.

Geometry

• You can now override the basis for curves using the -shapeedit flag to the Alembic procedural.
• Fixed a potential crash seen on extraordinary Catmull-Clark meshes with __faceindex primvar attached.
• Improved performance for edits to large numbers of geometric mesh lights.
• The Alembic procedural will now attempt to apply velocity based motion blur for single frame archives.

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