Peter Herth пишет:

Well, I had no use for them so far, but as with many Tk features, I might have
overlooked a cool use case. So can you give an example where you use canvas
units?

I simply draw a plan of real objects and it is more convenient to do this
in real coordinates, not in pixels, moreover, pixels are not always of same
height and width, that is, not always circles. So measuring in pixels would
lead to axis of X and Y being unisotropic.
I may be wrong here but this was my first idea when I decided to use millimeters.

Yeah, looks like a good solution and I will merge it in.

I can provide the full source file if it is needed.