I’ve been investigating Substance Painter and how to best select parts of a model. One such option is by using an ID Map, essentially a flood-fill of random colours per material zone. Wendy very kindly brought this to my attention in a recent stream (thanks, Wendy!), and before I forget, here’s how to do it.
First we’ll import out model and enter Edit Mode. I’ll pick a white mat cap and display the polygroups in the viewport, then head over to the Tool – Polygroups Menu and select Auto Groups with UV. Notice how the colours on your model change when you do this.
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Now we’ll head over to the Polygroups menu and choose Polypaint from Polygroups to transfer this information over as vertex paint.
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Let’s create a texture next and bake this out so we can use it in Substance Painter later. To do that, head over to the UV Map option and set a suitable texture size. Also under Adjust, select Flip V to rotate our texture by 180 degrees otherwise our map won’t work in Substance Painter.
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Under Texture Map, select New from Polypaint. This will create a new texture for us, enable it on out model, then transfer the polypaint colours over.
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Our final step in this process is to export the map. Select Clone Texture and it’ll be made available in the brush settings tab on the left. Right-click on it and select export. You can also do this from the Texture menu (same approach, right-click on the texture).
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That’s it! With this new ID Map, we can go ahead and select/mask parts of our model in Substance Painter. I’ll cover how to do this in another article.