Padding issue
interpolator
UPDATED images with extreme case scenarios. While it's rare these will be visible, there are projects where texel density is too low and they become an issue:
I have the following issue - I have to bake some very low res maps, and I noticed pronounced hard edges with bakes in 3dsmax and xNormal, but near perfect with Maya. All hard edges have UV splits, always baked with a cage. After some testing this is what i found:
EDIT, Clarifications:
- baking with 0 padding in Maya, Max or xNormal gets the same result (visible hard edge, artifacts, standard issues when you don't use padding). Every solution to add padding after bake (dilation, ps actions) acts by extending the border pixels, but I still get the visible hard edge.
- baking with padding (no matter the value) in Max and xNormal improves the hard edge by a tiny bit, but the padding works by stretching the border pixels outwards, so they are the same color - similar to dilation.
- baking with Maya with padding (starting from 1 pixel) adds another row of pixels inside the UV border, and then everything that's extended it's a different color (as in the picture above in the different shades of purple). It's totally different, and this and only this gives the super smooth perfect edges (even at 128x128 res)
The hard edge shows up with the bake from xnormal/Max, both bakes with padding 4, 64x64 resolution.
What's happening here? How can I fix this inside 3dsmax?
Replies
Maya looks like its expanding the pixels based on the normal and max looks like it just going straight along the x axis.
If you want to bake in max, xnormal has a dilation function in photoshop that works well.
My experience has always been that maya bakes better normals than max.
If I bake both in Maya and Max with 0 padding, the results are the same, there's that hard edge that shows up (top right screenshot). Only when starting to add padding in Maya something changes and I get the good results, so increasing the padding after bake might not help - I need to have more saturation/gradient in the edges (like in the Maya bake with padding), at least that's what I think, but I don't know how to recreate the results in max or xnormal.
Maybe I just never noticed them before.
In any case, I tend to handle padding in photoshop when all adjustments are done. I like to blend the UV islands (with 0 padding) into the padding itself so there aren't harsh transitions. I did this on some sci fi chess mechs and I liked the results much more than from the bake.
I think maya do better job here becouse it "'see" information beyond uv shell seam and interpolated this to pixels on the edge of uv. "Fill texture seam" function just make that effect more visible.
Max, Xnormal, Modo, Blender from my test just ignore information beyond uv shells. Completely stop raycasting right on pixels on uv edge. But in most cases right on uv seams of lowpoly we have dramaticaly angle changes of hipoly surface, that need to be baked to be interpolated info in pixels on uv edge.
Crapy workarounds only, like place exaggerated flat!(not round) chamfers on hipoly along uv seams of lowpoly... That makes information before and after uv shell pretty match the same and for baker no need to see information beyond uv shells to make almost correct result on seams.. (
or... bake in maya.. pff.. but would be nice to see a another solution
hope i was understandable
yeah maya is slow, but damn it bakes the best normalmaps
We work in our studio on our proprietary(for now) baker with some nice features like "skewing control", "raycast from lowpolys intersections" and of course baking pixels beyond uv shells instead of just padding.
Still in early pre alpha production prototype stage, but our artists in company(not freelancers) already baking only in it all the time now and love it. Hope we can deliver it for everyone, if anyone will need it.
Not the best example, but thats what i have for now to show something:
And if raycast from intersections works as I think it does...wow.
Unfortunately there is no place to sign up for now, sry.
Its too early, baker in pre alpha stage, have no proper ui, we did not think about where or how to deliver it yet.