Author Topic: Baking Problems with Normal & Cages...  (Read 20968 times)

I'm baking a monster character from high to low poly in Substance Painter. I have the latest version of Substance Painter (1.3.4 steam). I tried baking without the cage file and it looks nice except for the torso which has extruding normals which looks bad. I then tried baking with a cage file for the body. It solves the problem for the extruding normals but then it creates little grayish(shinyish) things around my model which is not good at all. How can I fix this? Any settings to change in the baker or is it possible to paint on the normal map ( or normals) and paint over the little artifacts? I attached some screenshot to further explain my problem. Thanks!

How is the cage made? I have found that a duplicate of the low-res pushed out a little gives me the best results. Same UVs needed as well. That said, I am by no means a ninja at cage baking, others may have proper explanations as it's still a sort of black magic to me.

This guy from 100,000s to 3000 poly, baking with the low-res pushed out a couple of cm:

Last Edit: May 04, 2015, 08:39:43 am
Slow is smooth and smooth is fast

I made the cage inside of maya using this guide from the Unreal documentation:

I just tried not using the cage and making the max frontal and rear distance very low like .001 and .01. It looks really good now. Is there a better way to make cages or what?

It looks like your cage is not completely covering the high res. mesh.  Usually its a good idea to bring the high mesh into what ever 3d content creation program you're using and make sure the cage completely covers it.  Also are you sure its a normal map issue?  it almost looks like a Ambient occlusion problem.  You can easily solo the different maps in painter to verify the results.  Under the viewer panel click on the down arrow on mode and select addition map.  Then below that in the map window you can see your different maps.  What the cage mesh does it sets a limit for the bake engine to search for data to bake.  So If you have a high res. mesh that has alot of bumps and extrusions in it, the cage need to cover that.

And like Badger said earlier, when you create a cage mesh, it need to be an exact copy of the low mesh, including UV layout.  The only thing you can do to a cage mesh is transform the verts or faces to cover the high mesh.

I tried many times of different variations. My model is completely covered and I tried a exact copy of the low-res model and an slightly blown up model (away from vertex). Yes, it both the normal map and ambient occlusion map. It seems to me that sometimes not having a cage is the best way to go.

You have an awful long list of hidef meshes in your baking setup. Just to make sure, try having just the one that you need and nothing else.
Slow is smooth and smooth is fast

With a cage I would attempt adjusting/moving individual vertices to cover the trouble spots.
Anyway to answer another part of your question. Yes you can fix the normal map, by taking it into Photoshop (or other program) and using the smear tool carefully. It works perfect, I have done it.

Another baker is xNormal.

From your screenshot it seems the bake with the cage missed the high-ply mesh, creating holes in the textures. Thoses holes have been filled with the dilation (padding) and the diffusion process applied to the textures. That's what the shading looks odd. I would suggest pushing you cage a bit further in order to cover the maximum area possible of your high poly. You can also bake without a cage if you tweak the rays distances properly.

Adjusting the cage manually or fixing the normal map in Photoshop are really not good solution. They work of course, but they are destructive workflow and each time you will update your mesh or you high-poly you will have to redo them. It's better to take the time to tweak the baker parameters than modifying your map/cage manually (which can be lead to other errors).
Don't forget your log file. It can be exported from the Help menu of the software.
Fabrice Piquet aka Froyok. Product Manager, Technical Artist and Documentation at Adobe.

Why the cage UV needs the same 'UV' with low mesh?
I've tested changing the UV (different UV with low mesh) of the cage, and the error occurs.
I solved the problem by using duplicated low mesh and using it as a cage mesh (modified the size to cover the low mesh)
BUT I still don't get it why the cage mesh needs the UV information.

And this is why the 3ds max exported cage file isn't working properly when I use it as a cage in Substance Painter.

Anyways, Thanks to "Badger"

Last Edit: February 26, 2019, 05:23:26 am

And this is why the 3ds max exported cage file isn't working properly when I use it as a cage in Substance Painter.

You can create cage by duplicating low mesh and pushing it or using projection modifier. Both methods preserve low-poly's UVs.