[node tool] Scale selections around center of rotation

[Stratadrake]

When selecting objects, the center point that appears when the skew/rotate handles are displayed should also appear with (and be applied to) the scaling handles as well.

I ran into a situation the other day while planning out some typometrics with nodes along a path: I wanted to scale part of a path to be a set size, with the other nodes scaled in proportion. An available workaround was to set guidelines and snapping, but it would have been much faster if I could simply move the center of scaling and then transform the path accordingly.

[su_v (suv-lp)]

a) scale about rotation center:
Press <Shift> while dragging the scaling handles to scale from the rotation center, <Shift>+<Ctrl> to scale proportionally from the rotation center. It uses the same rotation center that is visible with the skew/rotate handles (i.e. it even scales around a dragged/moved rotation center)

<http://tavmjong.free.fr/INKSCAPE/MANUAL/html/Transforms.html#Transforms-Mouse-SRS-Scaling>

b) visibility of rotation center:
Duplicate of bug #171251 “Visible Rotation center handle when rotating selection.”
<https://bugs.launchpad.net/inkscape/+bug/171251>

[su_v (suv-lp)]

In the select tool, the base point of the scaling transformation (opposite bounding box corner or rotation center with 'Shift') is displayed as soon as you start dragging one of the resize arrows.

c) select tool vs node tool:
After rereading your report it seems I misunderstand your request and this report is about the transformation handles of node tool which don't display the rotation center while resizing nor take a temporarily moved rotation center into account when 'Shift'-dragging a resize handle.

Related report:
Bug #590261 “[Node tool] Scale/stretch/skew transforms with transform handles don't snap”
<https://bugs.launchpad.net/inkscape/+bug/590261>

[su_v (suv-lp)]

Apologies for my sloppy testing:

> nor take a temporarily moved rotation center into
> account when 'Shift'-dragging a resize handle

The rotation enter _is_ taken into account, the missing features are:
- display rotation center while scaling selection of nodes
  (consistent with the select tool)
- use global snap settings when dragging the
  transformation handles of selected nodes (bug #590261)

Changing status to 'Wishlist'.