Feature Request: "Pass through" mode for layer groups

[AsamiImako]

This feature request is mostly for keeping larger painting projects tidier. It would be helpful if layer groups could be set to a "pass through" mode where all the layers inside act like they are their own separate layer so that layers can be sorted into folders without changing how the final image renders when using blending modes like multiply, soft light, etc.

[ucupumar]

I'm not sure that I'm getting what you meant by passthrough mode. Can you give some examples?

[AsamiImako]

Sure. I've attached a few screenshots I set up in GIMP to help demonstrate. In these screenshots, Layer A is a plain color, Layer B is set to "Soft Light" blending mode, and Layer C is set to "Multiply" blending mode.

In this screenshot we have an example without Layer Groups, all the layers are evaluated based on the layer below them:

In this screenshot we see what you get when you place these layers into a layer group normally (and the same behavior seen in Ucupaint in Blender). Now, layers B and C are evaluated on their own, and the result is layered on top of Layer A. This is useful in its own right, allowing you to compile multiple images and have them evaluated as a whole before layering the result on top of the image beneath them:

Sometimes however, you just want to create a group for organizational purposes but still have the layers evaluated as they are without the group. For this, you can in GIMP (and what I am proposing for Ucupaint) set the layer mode to "Pass Through" which is what you see in this screenshot. Despite layers B and C still being inside the group, they are instead evaluated as though they were all separate layers again:

[ucupumar]

Oh, I see, but it won't be possible to add masks to this kind of group.

[AsamiImako]

Even without masks I think this sort of option would still be nice purely as a way to keep large projects organized, especially combined with the other feature request I made that would allow for collapsing these groups. Just as an example here's a texturing project I have been working on for a head. It has so many layers I had to zoom out quite a bit to get them all to show on a 1440P monitor. Being able to sort things into groups while I am working and collapse them would make it easier to focus on the specific parts I'm working on and reduces scrolling through the long list.