I'm sure that Inkscape can do the following; I ust can't figure out how to get there.

What I need is a rectangle, one quarter missing, and all corners rounded (let's say an L-shaped box; by the way, does this shape have an English name?). The shape is easy enough to create with a boolean 'difference', but then I can only round 3 of the 6 corners; the corners resulting from the Boolean operation cannot seem to be rounded at all.

If anyone knows how to do this, help would be much appreciated! Thanks, Niels

This worked for me, in v0.46:

1. Create a rectangle that is one quarter the size of the final rectangle, and give it as much rounding on the corners as you want for the final one.
2. Duplicate it twice, so you have three of them.
3. Align them to approximate your final shape. You can use the Align and Distribute dialog (Shift-Ctrl-A) to align them precisely, or turn on node snapping.
4. Perform a union on all three: select them then Ctrl-+, or Path -> Union.
5. Now you'll have three gaps mucking up your shape. With your shape selected, switch to the Node tool (F2).
6. For the two gaps on the outside edges, just select the node at the point of the gap, and press Ctrl-Del. You need to hold Ctrl when deleting so that Inkscape doesn't try to preserve the shape of the deleted node, it just deletes it.
7. Now for the inside corner, do the same thing. Select both nodes that are at the points of the gaps, and press Ctrl-Del. It should give you a corner with the same "roundness" as the outside corners.

Let me know if my explanation is unclear and I'll try to post some pictures of the process.

If you didn't need to round the inner corner, another method is to use offset. It'll round corners that are less than 180° when increasing the object size.

Sadly, neither suggestion gives the intended result. I maybe should have mentioned this before, but I want the inner corner to be 'negative' (270), and the suggested method seems to give me a positive 90-degree angle. Any more bright ideas?

thanks,
Niels

I guess I don't know what you mean by "negative" and "positive". Here's the shape I created with the instructions I gave:


How can the inner corner be "positive"?

Here's a visual run-down of the steps.

1. Approximate the shape


2. Union


3. Select and delete the unwanted nodes


4. Done


Are you looking for a shape other than this? If so, maybe try posting an image of what you want.

That's a good technique, kelan. I would never have thought to do it that way.