mrdoob
USDZExporter: Support metalness/roughness factor and Image combination
Is your feature request related to a problem? Please describe. Currently in usdzExporter , the roughnessMap and metalnessMap is only exported if roughness is 1 and metalness 1. https://github.com/mrdoob/three.js/pull/22201 this was due to the limitation that usdz generated does not have support for both a factor and image .
A clear and concise description of what the problem is.
On a metal ring model I exported which had roughness of 0.75 and a dark roughness map , due to the conditions above the image was skipped and the model was exported with just float inputs:roughness = 0.75 which made the usdz model very rough and inconsistent with the three js render
Describe the solution you'd like Since there have been some good updates from @sunag and @yuta-hayashi ,I was wondering if we can revisit this topic and implement a alternate solution
I was looking for references but only found this one based on NodeGraph:
Do you know some other reference too?
https://github.com/PixarAnimationStudios/USD/blob/dev/pxr/usd/usdMtlx/testenv/testUsdMtlxFileFormat.testenv/baseline/NodeGraphs.usda
something from here might come in handy https://github.com/google/usd_from_gltf/blob/master/convert/materializer.cc
from usd_from_gltf
Possibly related: this example when loading AR on an iPhone uses USDZExporter to create the file for Quick Look, but we get the message "Object requires a newer version of iOS", which is Apple's lovely message meaning something went wrong parsing the USDZ. In this case, the object has a factor but no texture at all. Does anyone know if there's a way to support that in USDZ? @mrdoob @grorg.
@elalish The case of zero textures and just factors like roughness:0.1 and metalness:1 should export correctly , like you said that error message can be caused due to wide variety of reasons (one silly case i remember is presence of symbols in the material names )
Made a fiddle please test it out, (the usdz file can renamed to .zip and can be opened on any os and the materials info can be checked)