Random Object and Material color passes

In other software it's super easy to make a random color pass either for per object or per material to ease the area selection and masking process in compositing software like Photoshop or Krita.

So, you have the beauty version of the image:

And this is what would be needed (the image below). The following image is painstakingly achieved by putting a single emission node for each material. I'm sure this could be automatized easily . Other way is to assign material IDs to each material and in compositing editor collect them all into one image - but that too takes way too much manual work, as well.

You can achieve relatively functional random colors for every object by assigning an override material for the render layer. A material that has the following nodes. But you would need this seed suggestion in order to add also color values (black, grays, white) into the final colors mix (which helps the selection in Photoshop)

And the result. Not very good, in fact because all the objects use same color value, only hue is different, which causes too many objects to have almost the same color.

So.

Can we have a simple way to render out a proper Random Object color pass and a Random Material color pass? Pleeease? :)

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