I've been a long-time user of Photoshop. Much of my artwork is for 2D game graphics - sprites, instrumentation and dialogue box backgrounds. Most of the visual effects I create involve a chain of Boolean combinations of the opacities of layers and the levels of channels. A good example of such an effect is creating in a channel a height map for Lighting Effects combining channels of rendered type, fine-grain textures and strokes representing chips and gouges to render a decrepit stone slab with Celtic knots around the edges. In between the Boolean operations, I often move (with the nudge cursor keys), blur or expand the selection. In typical non-destructive fashion, the Celtic knots source images are kept as an assembly of pristine tiles, bi-level except for antialiasing. Their 3D shape is determined by various blurring, curves adjustment and Boolean operations applied to a copy, along with channels representing damage. Other examples include dry-brushing, shadowing and ink wash effects applied to the rendered image, using the same source masks as used in the construction of its height map.

To this end, I very frequently used the Photoshop interface for loading and modifying the current selection with the opacity of a layer or its levels (viewed in the Channel Palette). Pressing Ctrl and clicking on a layer or channel thumbnail loads that layer's opacity or that channel's levels into the current selection. Additionally holding down Shift (add), Alt (subtract) or Shift+Alt (intersect) performs the Boolean operation on the current selection, which may be used directly or saved as another channel. Much of the time, the operations I perform require no change of state for anything but the current selection and require no interaction with dialogues. Hence they are quickly and easily performed.

To some extent, I can use Krita's saved selections, but performing Boolean operations with them is slow and complex and the many state changes make me dizzy. Making any one of them an active selection makes me fear that their data will instantly be lost when I go to another layer and start making a new selection. Local selections are especially frustrating because I can't find a way to quickly transfer the selections to be used on other layers.

As Krita's layer palette is not divided between Layers and Channels as in Photoshop, there may need to be a UI mechanism to select opacity or levels or even individual colour channel levels. An extra qualifier key or a Ctrl-swipe to select a colour channel or levels, perhaps.

Yes, we have a wishbug for this already: https://bugs.kde.org/show_bug.cgi?id=346892

It seems from the wishgroup categorisation that we categorised it as two weeks of work if you understand the layer-docker code.

We actually do have the channels seperate as the channel docker. However, we lost per-channel editing somewhere between 2.7 and 2.8, so we need to bring it back properly(phabricator task: https://phabricator.kde.org/T331). Until then there's the per-channel blending modes(copy red, green, blue).

But yes, the selections overal should need some ux thought. We have global selection masks as well, which handle the global selection(meaning that you can't modify local selections accidentally), but it's not self-evident apparantly.

TheraHedwig wrote:Yes, we have a wishbug for this already: https://bugs.kde.org/show_bug.cgi?id=346892

Ah, a new place to submit search requests. Cheers!
[reads]
Ideally the functionality will apply to levels-like data, too, so that by a qualified click of the appropriate thumbnail, the brightness of an image, layer or channel can be involved in a Boolean selection operation as easily as would be done for opacities.

[Finds Channels docker]
Ah, there it is! Yup. It's definitely not affecting edits. When it gets serviced, I would quite like to see both visibility and write-enable controls for visible channels. I think the channels docker would be an ideal place for the levels mode of Boolean selection operations. That way, Ctrl-clicking a thumbnail on the Layer docker need only ever refer to opacity.

It's alright, we actually prefer having threads in the forum for new feature requests first, so that artists can help each other define themselves better, and we get a better idea of the workflows this involves