Implements discussion #605. The diagram editor can already export a folio
to SVG; the element editor, where a single .elmt symbol is drawn, had no
export capability at all -- confirmed by grepping its header for "export"
before starting: nothing.
## Renders the live scene, not ElementPictureFactory's cache
The discussion proposed sourcing this from ElementPictureFactory's cached
per-element QPicture (m_pictures_H), the one used for the elements-panel
preview icons. Checked that cache's actual invalidation before building on
it: nothing in the editor ever tells it to drop an entry on edit, and it is
keyed by the element's on-disk uuid. So for any element already previewed
once in the panel, exporting from the cache would silently produce stale
content after any edit; for a brand-new, never-saved element, no entry
would exist at all. Neither is acceptable for a File > Export action a
user expects to reflect what's on screen right now.
Renders ElementScene directly instead, the same way
ExportDialog::generateSvg() already renders the live Diagram for the
diagram editor's own SVG export: no new drawing logic, only a new playback
target (QSvgGenerator instead of the screen), sized to the element's own
content bounds via the existing elementSceneGeometricRect() helper.
## Hotspot cross excluded from the export
ElementScene::drawForeground() draws the red origin/hotspot cross on every
render() call, unconditionally -- it's an editing aid, not part of the
element being drawn, and diagram editor's SVG export has no equivalent
problem since Diagram doesn't draw one. Added a settable
hotspotVisible flag, defaulting to true (the existing editing view is
completely unaffected) and turned off only for the duration of the export
render() call.
## Verified end-to-end via a real Xvfb session, not just a build
Opened a real shipped element (en_60617_05_06_04.elmt, "Phototransistor"),
exported it, and rendered the resulting SVG back to a bitmap with a small
QSvgRenderer-based harness -- pixel-identical in shape to the element as
shown in the editor. Confirmed the file is valid XML and contains no
red/#ff0000 stroke (the hotspot cross did not leak in).
Then the case the whole "render live, not cached" decision was about:
opened the same element, drew a new line with the line tool, and exported
again *without saving*. The new line is present in the exported SVG.
git status on the source .elmt file after both exports shows it completely
untouched -- the export is read-only and reflects live, unsaved editor
state, exactly the property a cache-based implementation would have gotten
wrong.
Built clean, no new warnings.
Displays the cursor's scene position (same grid units as the parts'
X/Y property spinboxes) in a permanent status bar label, updated on
every mouse move. Addresses the overlapping-node mis-click case from
the originating forum report: with a live readout, precise pointing
no longer requires guessing against nearby z-ordered points.
ElementScene::mouseMoveEvent already computed the (optionally
grid-snapped) scene position on every move; it now also emits it via
a new mouseMoved(QPointF) signal, which QETElementEditor's status bar
label subscribes to.
ispyisail