rotation of compound objects fails

[R. Moeller]

Ubuntu 12.04.4 LTS
xfig: 3.2.5.b-2ubuntu1

In xfig 3.2.5b, the rotation of compound objects by angles different from multiples of 90 deg fails if another object is present which cannot be rotated for the given angle.

The bug can (hopefully) be reproduced as follows:

1. Draw an object which can be rotated by arbitrary angles, e.g. a polyline.
2. Select rotation angle different from multiples of 90 deg, e.g. 15 deg.
3. Rotate object -> works.

4. Draw second rotatable object, e.g. also a polyline.
5. Glue both objects into a compound object.
6. Rotate by 15 deg -> works.

7. Draw a third object which cannot be rotated by arbitrary angles, e.g. a box.
8. Try to rotate the compound (containing the two polylines) by 15 deg -> ***FAILS***!

9. Delete box object.
10. Try to rotate the compound -> works.

Rotation of the compound only works for multiples of 90 deg, if the box is present.

[Romano Giannetti (romano-giannetti)]

I think that this has been like that since forever. xfig tells you "invalid rotation for this compound object".
So really not a bug; maybe a missing feature.

[R. Moeller (rsuzzoop)]

I'm aware that you cannot rotate compounds which INCLUDE an object that cannot be rotated by arbitrary angles; this is probably what you refer to, but it is NOT the problem.

The problem is that you CAN rotate the compound if it stands alone, but as soon as an object OUTSIDE this compound is drawn which cannot be rotated by arbitrary angles, rotation of the rotatable compound suddenly also fails. To me it looks as if a check goes wrong: Rotation should check whether the compound to be rotated contains a component which cannot be rotated by arbitrary angles. What happens is that somehow other objects outside the compound that should be rotated are checked on whether they are rotatable by arbitrary angles.