Baker supporting alpha maps ? 2019 edition

Noors

Helloooo,

long time running pain...

Is there actually any baking software handling alpha transparency ? I need to bake tiny planes with an alpha (a round gradient) onto some other mesh.

I have sort of automated the process to render a top camera over a UV mesh

One render per uv element, per texture type, then composite all maps, padding...blabla.

It's long, and it works only because i bake on flat elements.

Painting in substance is not relevant.

gnoop

There was a thread here regarding the issue.  Sorry don't have a link.   Someone suggested Vray and Arnold could do it in Max but not directly, using special override shaders.   

   From what I did personally :  Modo can do it if you kill padding   ( did it years ago and it's kind of shady now how I did it exactly but it definitely could)

   Clarisse  could bake it and pretty well actually  but have very typical limitation : a target low res surface shouldn't cross/intersect  hi res objects.  Making it kind of a problem for things like foliage.

 Octane GPU baking camera could do same with same limitation. Quality of baker is sometimes questionable although . Have lots of weird glitches.

 

Eric Chadwick

TexTools used to have a UV Flatten tool that would lay the UVs out in model space. Maybe it still has this in Blender? 

gnoop

Here is baking a dry leaf (with displacement) onto surface of a sphere (object space normals)  using alpha as a "clip map"  in Clarisse.     Same "clip map" idea should work in other renderer too.    I recall somebody did it even with Mental ray  years ago. Involving some extra pain in the a.. I kind of don't remember what it was exactly.   Separate "pass" or something and special shaders. 

In Clarisse it's plain simple , no need of any workarounds and in general much less of a pain than the scattering same kind of alpha things in Substance Designer, much better controllable, interactive with super huge amount of things , speedier to preview and "lookdev"  but unfortunately much longer to render /bake final image since it's all cpu based.

Noors

Thanks for the info. I assume clip == cutout. I don't remember if baking cutout works in max, will check it.

I would need alpha transparency tho because i want gradients.

A separate pass won't work.

Yeah Eric, i already use a flattened mesh.

gnoop

Yeah, Clarisse clip map doesn't work with gradients. I am afraid nothing would probably. it could bake opacity of material  but making lots of artifacts. And sorry , Octane seems having issues with that too or I forgot how I did it there already.   In Modo I also did it for leaves so not sure how would it work with gradients

gnoop

Modo Indie seems can't bake translucent alpha either using same clip/cutout/stencil  idea. Same as other renderers.  

poopipe

You needed to use cutout with mental ray in max 

Noors

Yeah i guess it's related to the general raycast baking algorithm. Cutout objects are considered opaque so there is no issues with them.