There seems to be an open issue about this here:
Is there a way to apply a shader modification to achieve this in the mean-time? It’s possible to add custom uniforms using onBeforeCompile so I can add a vec3 for the rotation and I can insert a transform somewhere in the shader but I can’t see where to add the transform.
The env map direction is controlled by envmap_fragment. This is included in some of the main material shader types. For some reason that include isn’t in meshphysical_frag though so I’m not sure where the envmap chunk is being used there. But I could modify the reflectVec in envmap_fragment with the custom uniform.
How do I modify those chunks? onBeforeCompile shows the main shader so I could paste the whole modified shader in but where is meshphysical_frag processing the environment map?