Creating a material and changing its color

Omniverse Isaac Sim
1

I created a cube primitive and now I want to create a material and bind it. It seems that creating a material from stage.DefinePrim is a bit of a hassle as one needs to create a shader and connect things. So I did it through the kit commands instead.

mtl_created = []
omni.kit.commands.execute("CreateAndBindMdlMaterialFromLibrary",
            mdl_name="OmniPBR.mdl",
            mtl_name="OmniPBR",
            mtl_created_list = mtl_created)
mtl_path = mtl_created[0]
omni.kit.commands.execute(
            "BindMaterial",
            prim_path=cube.GetPath(),
            material_path=mtl_path
        )

How do I change its diffuse color though? I tried using the attribute from the shader but it cant be found.

shader = self._stage.GetPrimAtPath(mtl_path + "/Shader")
color_attr = shader.GetAttribute("inputs:diffuse_color_constant")
color_attr.Set(Gf.Vec3f(0.6, 0.13, 0.13))

I also tried using the command but thats not working and even it were working it needs to know what the color was previously for some reason.

 omni.kit.commands.execute(
            "ChangeProperty",
            prop_path=mtl_path + "/Shader.inputs:diffuse_color_constant",
            value = (0.76, 0.15, 0.15),
            prev = (0.2, 0.2, 0.2)
        )
1 Like
2

Hi parrotdora,

please check this part of the documentation, it might help you out.

Kindly,
Liila

3

Given the documentation you provided, what is the corresponding code (python) then to simply change the color of a primitive object?

4

This document will be helpful for that: Scene Setup — Omniverse IsaacSim latest documentation