I've ported the shaders shipped with the plugin to URP, but the material doesn't seem to be actually replaced when I start to paint. However, the vertex colors are actually “painted” and passed to Houdini. The output is correctly, but my users can only paint blindly.
I've also tried to change the shader in the plugin settings, instead of modifying HoudiniSpecularVertexColor.shader in place, but it doesn't work neither.
I am pretty sure that the ported shader is correctly. To verify:
1. I create a material from the modified shader.
2. I replace the materia of the mesh which I want to paint with the material created in step 1.
3. I start to paint by https://www.sidefx.com/docs/unity/_painting_editing.html [www.sidefx.com]
4. I can see the painted vertex colors.