Here's an example of what I'm trying to achieve:
1. Start a layer group, such as "Character 1"
2. Add a mask to define the character's form.
3. Create a normal layer, such as "Clothes"
4. Add a mask to define just the clothes.
5. If possible, I want the mask to be defined using vectors rather than paintbrush, in particular for parts with really sharp lines. For example, you want to make a photo frame, and of course it'd be easier to edit in vector form.

Now, I've found a Wonderful solution thanks to Krita's "Erase" option:
1. Create layer group
2. Draw all the sub-layers I want.
3. Create a sub-layer, called "mask", on top of the other sub-layers, and set it to "erase" mode.
...
4. Profit!

Now the thing is, I'd like to use vector shapes for the task, and although I have both Krita and Karbon compiled now, I can't seem able to make a shape with a "fill." Help? (incidentally, the pictures for Karbon's tool icons don't seem to be showing, though it may be because I don't have Oxygen installed, or something like that. They can still be clicked though).

Also, it'd be nice if I could just draw some of the shapes in Inkscape and import them, but so far Krita doesn't seem to preserve the layers. Is it possible to preserve the layers? Thanks!

Wait, I just realised that Erase does the opposite of what I want, which is to draw which parts are transparent rather than punching holes... Is it possible to implement a mode called "show only", similar to masks? Either that, or is it possible to make masks visible on-screen so you can properly work on them?

The fill can be change with the "Styles" docker. There are also tool for pattern and gradient fill.

Layers are not preserved currently. The next version will be able to do that. For now you can open it with Karbon and then copy and paste to Krita.

Thanks for the tip! The copy/paste doesn't seem to be working though, unless there's a special way of copy/pasting.

Is it possible, by the way, to:
- Convert a normal layer into a mask
- Make the mask visible on-canvas so that you know what you're doing
- Paint on a mask rather than use the eraser tool
- Use vectors as a mask?

Thanks!

You need to be on a shape layer and have the default tool activated.

Other questions:
-Not directly, but you could try convert the layer to a selection and then create a new mask. The new mask is based on the selection.
-No, still missing
-No, masks only work between completely filled and erased. So no gray-white
-No

Hey, it works! Thank you very much! It still doesn't preserve layers, but I can copy/paste them one by one.

1. Oh, that works! I can reproduce what I'm trying to do now by making the selection and inverting it, then make the mask by erasing the borders. As long as I don't paint too far away from the masked area, it only shows the area I want it to show.
2. So it's a planned feature at least? Good to know!
3. Oh? Will it work on grayscale in the future?
4. Could I submit this as a feature request?

Thanks for the quick responses!

2. Yes, it's planned.
3. Grayscale masks are in discussion. Not completely decided yet.
4. Sure.

Uh... I can't find where to submit feature requests. But never mind, I see that improvements to layer mask are on the to-do list, and that takes priority. If that's done, then it takes care of a lot of things already!