Non-PBR paint-over question

[motorsep]

Hello,

I'd like to paint on my Android tablet on a low-poly 3D model with pre-baked (in Blender or elsewhere) AO/curvature texture as reference (in a separate layer). The goal is to end up with something like good ol' Quake 1 character skin (doesn't have to be pixely - in-game shader will make it so).

Is Armor Paint well-suited for something like that or is it strictly for PBR painting ?

Thanks

[motorsep]

@luboslenco So I bit the bullet and purchased Armor Paint for Android. Would really like to hear back from the dev ;)

[luboslenco]

Sorry for late reply. Pushed several android updates recently so hopefully the experience is getting better.

What would you like to get improved the most? For non-pbr projects the roughness / metalness could be ignored I guess. Maybe a dedicated non-pbr viewport shading could also be added, like we do for celshading (by enabling viewport_celshade plugin in preferences).

[motorsep]

Sorry for late reply. Pushed several android updates recently so hopefully the experience is getting better.

No problem :) Thanks for getting back.

What would you like to get improved the most? For non-pbr projects the roughness / metalness could be ignored I guess. Maybe a dedicated non-pbr viewport shading could also be added, like we do for celshading (by enabling viewport_celshade plugin in preferences).

A non-pbr shading mode would be welcomed for sure, but if default mode can be made look like non-pbr it would be fine for now.
I haven't really gotten to work on the texturing in-depth yet, so I can't really offer proper feedback. When I do, I will definitely post my observations.

[u3shit]

Just to chime in what I wanted (and failed) to do.
I have also non-pbr/npr, but also the game engine allows some kind of recoloring of the textures, so I actually have more data than just the 3 RGB components to work with, so it's not something where a generic npr implementation would work. Seeing that I can create shaders that can write color and occlusion/roughness/etc I thought I could maybe use armorpaint.

Problem 1: materials (that node thing) can only be used by brushes, not objects/viewport. But the viewport shader glsl can be replaced by a plugin, so it's not the end of the world (you just have to make sure you load the right plugin with the right file).

Problem 2: you can't add other components to the layers. Digging around the code it looks like armorpaint was build with the assumption that a layer = 3 RGBA textures and period, noone on the Earth would need more than that anytime in the past, present or future. I was thinking about abusing, like, roughness to store something else, but then I have the problem that layer merging works differently for color and non-color textures, so I'd be pretty much confined to a single layer then. And even a hacky way of adding a new image to LayerSlot and handle it would require me to edit the code at hundreds of places, not something I'd like to do.

Is there any plan to do something about problem 2? I know, it's a big refactor to allow armorpaint to have arbitrary channels/additional data stored, but it would make it immensely more powerful.

[u3shit]

Oh, and one more thing. Filmic tonemapping (and the rest in compositor_pass.frag.glsls), while fine for PBR rendering, is generally a very bad idea with NPR. I guess the random pow(x, vec3(2.2, 2.2, 2.2))s in MakeMesh try to compensate for this somewhat, but it's far from perfect (for example, right now vec3(1, 1, 1) end up with something like 216, 216, 216 in the viewport instead of 255, 255, 255.