Proper way of painting ID masks on highres mesh

[Defonten]

I know this may be 3D soft-specific but may be someone knows the answer to my question still.

I’m struggling with exporting my highres polypainted in Zbrush model to Substance Painter. Of course I could do it in Maya or Max by just selecting needed polygons and assigning different material IDs on them, but with millions of polys in a scene it's a pain to select millions of polygons and assign IDs on them. So I would prefer having Zbrush's polypaint to act as Color IDs map. But highres FBXs which I export from Zbrush and then import in Substance for baking don't have IDs information - I tried all options (material/vertex color) What is the correct workflow for it and is it possible? Please help and thanks in advance! Thanks in advance!

[henrik_1]

But highres FBXs which I export from Zbrush and then import in Substance for baking don't have IDs information

You actually have to bake the ID map in Painter first (or import it from your 3d app if you baked your ID from there and just drag drop it into the ID bake channel, no need to do another id bake). 

If baking in Painter:
Make sure your low res has uvs.  The high doesnt need uvs but should already include your polypainted ID colors. If having subtools, use color fill.  Make sure ID bake toggle is checked in Painter.

Once you've confirmed the bake is good (it's not solid black when you polypainted with multi colors, for example), add a mask to a layer.  Right click the mask and add a color select filter.  This is where you can color pick from your ID bake.  If you get seams, increase tolerance setting.

Good luck!

[Defonten]

Thanks a lot for your reply. THe problem is that Painter's baker just can't read Polypaint information in OBJs. So in the end I just exported FBX directly from Zbrush and was able to bake ID map in Painter. Thanks a lot!

[dantrodgers]

Thanks a lot for your reply. THe problem is that Painter's baker just can't read Polypaint information in OBJs. So in the end I just exported FBX directly from Zbrush and was able to bake ID map in Painter. Thanks a lot!

I haven't had this problem, painter will read the polypaint data as vertex colour from zbrush when exporting as obj.  Make sure vertex colour is selected in the ID baker settings, which i think is default..