ctrl-dragging node handle does not snap to a line collinear with the opposite handle

[gpsnavigator]

In Inkscape 0.47, when you have a cusp node, with curves on both sides of the node, dragging and rotating handle of one side of the node with ctrl pressed snapped it not just to the 15° intervals, but also to an angle that was 180° opposite to the angle of handle on the opposite side of the node -> it made it possible to make the curve smooth without having to switch the node to smooth node, which causes both sides of the curve to move a bit.

In current revision from BZR (9488) it does not work, and ctrl snaps only to the predefined angles (15°steps), but not to the opposite angle. When it is dragged from an original angle that is not equal to a 15°step, it is able to snap to the original angle it was dragged from, as long as the drag is not released. It still worked in revisions 8882 and 8904, but it does not snap to opposite angle in 9104 and newer.

It behaves the same on both WIndows XP and Linux (Kubuntu 10.04) and on all computers where I used Inkscape, which is a lot of them. So it does nto seem to be anyhow influenced by what OS or computer is used.

Steps to reproduce:
I recorded a video from both versions (0.47 where it works and 0.48 BZR 9488 where it doesn´t work):
http://lugigalerie.wu.cz/inkscape/ink0-47.avi and http://lugigalerie.wu.cz/inkscape/ink0-48-b9488.avi
Text description: just draw two random lines connected by a common cusp node between them, change the lines to curves, and drag one handle of the node to some angle different than a 15°step, and drag the other one with ctrl pressed so that it "continues" to the opposite handle. in 0.47 it will snap exactly to the opposite angle and you get a smooth curve without using smooth node, but in revision 9488 it will snap to the 15° steps before and after the angle you want, but not exactly to the angle opposite of first handle.

It can be worked around by one-clicking on a handle when CTRL is pressed, thus "deleting" the handle and then making the cusp node a smooth node, which does not change the opposite side in this case. But it sometimes does nto work, and it is less comfortable than dragging to snapped angle.

[su_v (suv-lp)]

reproduced with Inkscape 0.47+devel r9489 on OS X 10.5.8

[su_v (suv-lp)]

Works in 0.47: snap handle to
- a line collinear with the opposite handle
- a line collinear with the opposite straight line segment

Fails in 0.47: snap handle to
- a line collinear with the original handle position
- a line orthogonal to the original handle position

Works in r9489: snap handle to
- a line collinear with the original handle position

Fails in r9489: snap handle to
- a line orthogonal to the original handle position
- a line collinear with the opposite handle
- a line collinear with the opposite straight line segment

Tested on OS X 10.5.8 (default settings) and compared with the manual for Inkscape 0.47:
«Ctrl+Left Mouse Drag: Snap handle to either a multiple of the Rotation snap angle (15 degrees by default), a line collinear with or orthogonal to the original handle position, New in v0.47: a line collinear with the opposite handle (if it exists), or a line collinear with the opposite straight line segment (if it exists). »
<http://tavmjong.free.fr/INKSCAPE/MANUAL/html/Paths-Editing.html#Paths-Node-Mouse-Handles>

[jazzynico (jazzynico)]

Some improvements in the trunk.

Works in 0.48.3.1: snap handle to
- a line collinear with the original handle position

Fails in 0.48.3.1: snap handle to
- a line orthogonal to the original handle position
- a line collinear with the opposite handle
- a line collinear with the opposite straight line segment

Works in r11652: snap handle to
- a line collinear with the original handle position
- a line orthogonal to the original handle position

Fails in r11652: snap handle to
- a line collinear with the opposite handle
- a line collinear with the opposite straight line segment