MAYA-121735: Add UV tangents directly in MaterialX #2113
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- Removes the arbitrary tangent code previously used with MaterialX native code that can generate U-aligned tangents in the presence of a texcoord stream. - Added stripped-down MaterialX graphs that provide compatible rendering of Lambert, Blinn, and Phong surfaces. The symmetric import export of these materials is lossless.
JGamache-autodesk
added
import-export
| @@ -387,18 +412,152 @@ MStatus _SetFAParameter( | |||
| // name for UV at index zero. | |||
| void _AddMissingTexcoordReaders(mx::DocumentPtr& mtlxDoc) | |||
| { | |||
| // We expect only one node graph, but fixing them all is not an issue: | |||
| for (mx::NodeGraphPtr nodeGraph : mtlxDoc->getNodeGraphs()) { | |||
| if (nodeGraph->hasSourceUri()) { | |||
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Mostly whitespace since we are not looping on all NodeGraphs.
| } | ||
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| // USD does not provide tangents, so we need to build them from UV coordinates when possible: | ||
| void _AddMissingTangents(mx::DocumentPtr& mtlxDoc) |
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New code to add tangent generators into the incoming graph.
| cmds.file(force=True, new=True) | ||
| cmds.move(6, -6, 6, 'persp') | ||
| cmds.rotate(60, 0, 45, 'persp') | ||
| self._StartTest('MayaSurfaces') |
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File includes a poly cube with standard surface MaterialX shading to show that the faces with Z-pointing normals render correctly now.
| // Grab the first st reader we can find. This will be the default one used for | ||
| // tangents unless we find something better. | ||
| stReader = node; | ||
| continue; |
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I'm not sure I understand why we can continue here. The first node def that matches will get the continue, the later if another nodeDef matches we execute the rest of the loop and maybe have a different behavior. I don't understand it in depth enough to know if it is a problem or not, it just looks a bit strange.
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We can continue here because we know that a geompropvalue node never has a tangent input. Note that we do not continue in the next branch because normalmap nodes have tangent input.
JGamache-autodesk
added
the
ready-for-merge
Removes the arbitrary tangent code previously used with MaterialX
native code that can generate U-aligned tangents in the presence of a
texcoord stream.
Added stripped-down MaterialX graphs that provide compatible rendering
of Lambert, Blinn, and Phong surfaces. The symmetric import export of
these materials is lossless.