Is there a way to perform per-UV island blur?
polycounter lvl 10
I'm doing curvature bake from a lowpoly mesh. Obviously, this results in a 1px wide curvature lines being left at the seams, since nothing like curved chamfers exists on a model. I'm interested in widening the convexity and concavity lines to get a certain world-space radius consistent across all my models. The most obvious way of doing it is through blurring (followed by leveling and other adjustments, possibly).
Only problem is, blur applied image-wide. Adding big bleeds to the bakes helps to prevent the disappearance of edges from influence of background outside of UV islands, but one more problem remains: leaking between neighbouring UV islands.
That's fixable: you need to apply blur on a per-UV island basis, therefore making outside samples nonexistent during blur of pixels belonging to each and every UV island. This can be done manually (grab a UV island mask from SD, open photoshop, remove background from a mask, start doing isolated selections + blurs or splitting isolated selections into layers, then blur each individually), but it would be very, very time consuming.
To think about it, island-isolated effects is probably a very widely applicable thing, useful for much more than widening my curvature edges. Basically, I'm asking for a blur directed like an inverse bleed. So I'm wondering if others actually found a way to automate that before. Is there any?
Replies
It will allow you to create a tangent space normal map that simulates chamfered edges on a low poly mesh. You'll get much better curvature bakes using the resulting normal map.