Hello

Im using 3dsmax with Arnold shaders, my mesh has 20 materials assigend to it. Because all the materials are assigned into one mesh, I have a MultiSub Object Material in 3dsmax. When the shader is exported into Houdini, the MultiSub Object is changed to a Switch Shader, and the index is connected to a parameter that uses a mtlID value to assign the shading groups, but in Houdini I can´t find a way how to use this mtlID or if i have to insert a different information here to make it compatible with Houdini.

Plan B

We tried a different approach, Im adding a custom attribute named shop_materialpath and the content is the "shader name" so the Houdini user can import all the shaders and automatically assign them.

We used this in Maya and worked, but Im having troubles exporting an alembic with 3dsmax.

When the .abc is imported in Houdini, there is no shop_materialpath attribute. If i export in FBX, Houdini detects this attribute.

There is someone who had experience in 3dsmax/Houdini workflow? Already asked in Autodesk forums but nothing yet

When we import the alembic in Houdini i have this data in the mesh, but i could figure out how can be used to assign the mat Ids

To resolve your issue, ensure that when exporting Alembic from 3ds Max, you configure the export settings to include custom attributes like shop_materialpath. If Alembic isn't exporting this, try using FBX as a workaround, which Houdini detects correctly. You may also need to script a process in Max to transfer material data as custom attributes before exporting. Additionally, in Houdini, you can write a custom script to map mtlID or shop_materialpath to shaders.