Hi,

1.
I have 2 vector shapes.
The 1st vector shape is a triangle.
The 2nd vector shape is a bigger polygon.
I want the polygon to have a hole, which has the shape of the triangle.
How can one do this?

Until now I've tried in vain.
I tried to place the triangle above the polygon and group both. Then I was looking for any operation to cut shape A out of shape B,
but I couldn't find anything like this...

2.
What's the best way to do the same as in 1. but this time not with a triangle hole in the polygon, but instead of a hole you have a red filled area?
Do you still create the polygon with the triangle hole and can fill the hole?
Or do you additionally place the triangle form above the hole and fill the triangle red? But doesn't that create cutter/printer problems, because you have double lines (triangle lines on polygon hole lines) ?
Or is it better to use the polygon without a hole and simply place the triangle above it? But doesn't that create cutter/printer problems, because you have double areas (triangle area on polygon area)?

1.Currently not possible. There are no boolean operations for vector shapes in Krita. I think it will come in the next major release.

2.Krita is not the most suitable application for cutter/printer jobs. it's way better to use something like Inkscape.
The vector tools on Krita are meant to be used as helpers for illustration/comic.

Thank you for the advice, artur89sd.
I'm tinkering around with Inkscape right now.
My impression is, that the vectorizing function of Inkscape is nice for quick & dirty work,
but fails when it comes to making a clean job like you would do manually.
So by now I know, that I will have to take my rasterized image and reconstruct it manually
by drawing vectors upon it.
I already figured out how to cut a vector shape A out of a vector shape B in Inkscape [selecting both objects, then (ctrl+-)].
But question no. 2 remains - as it turns out this question is independent of what software you're using, it's a general functional design question:

2.
What's the best way to do the same as in 1. but this time not with a triangle hole in the polygon, but instead of a hole you have a red filled area?
Do you still create the polygon with the triangle hole and can fill the hole?
Or do you additionally place the triangle form above the hole and fill the triangle red? But doesn't that create cutter/printer problems, because you have double lines (triangle lines on polygon hole lines) ?
Or is it better to use the polygon without a hole and simply place the triangle above it? But doesn't that create cutter/printer problems, because you have double areas (triangle area on polygon area)?

Does anyone know what's the best approach?

sunshinel wrote:My impression is, that the vectorizing function of Inkscape is nice for quick & dirty work,
but fails when it comes to making a clean job like you would do manually.

Try to make your raster image as clean and contrasted as possible, and bigger resolution also would help to improve vectorilization quality.
Also i think Inkscape has a function to simplify the shapes. You can try to play with this to see if you get a satisfactory result.

2. I think the best aproach would be this:
Draw both shapes.
Duplicate the "hole" shape
Subtract one of the "hole" shapes from the main shape.
Set the contour of the "hole" shape to a line width of 0px and color it white with 0% alpha so it will not print at all.
Color the shapes the way you want.