Custom debug color display for scene view?

What I’m looking for is something similar to the “Render Paths” view in Unity’s scene view, only with my own color-coding: The ability to give certain objects a custom color overlay in the scene view.
It would be great to use as visual feedback for level design tools.

Any idea if Unity provides such a feature or how I could achieve something similar without changing every object’s material?

screenshot from Render Paths view

Thanks!

The closest thing you can get is to use Gizmos. See DrawGizmo.

If you want to draw some kind of overlay you could render the scene again with Camera.RenderWithShader. Take a look at the Replacement Shaders.

If you want to render the scene completely with your custom shader you should be able to use Camera.SetReplacementShader on the scene camera. To disable your render mode use Camera.ResetReplacementShader