In an attempt to create an orientation Gizmo like those in 3d software, I have been using 3d Holographic Buttons, rotating them to my desired position. However, the top and bottom buttons present strange behaviors. The text on the top seems to be always white and the text on the bottom looks really saturated. What can be done in such a case? Below you can see the PG code.
.
The 3D GUI manager is creating a utility scene to host the 3D GUI buttons like the holographic buttons.
In this scene, it also creates a default hemispheric light and what you see is because the direction of the light is (0,1,0), so the top face is fully lit whereas the bottom face is not. You can try to change the direction of the light or even remove this light and add another one (a directional or point light, for eg).
You can access the utility scene with: manager.utilityLayer.utilityLayerScene:
In this PG I have added another hemi light with direction (0, -1, 0) so that all faces are lit in the same way.
That worked like a charm, thank you very much!