Grouping/ungrouping of filtered objects (groups|texts|clones) makes them disappear temporarily

[Tom Dignan]

Unsure of how I created this SVG initially.

Open this SVG, click the only group in it, and C-sh-g to ungroup. The group of rectangles on the left will disappear, but the text will not.

Revision 10956.

[su_v (suv-lp)]

Partially reproduced in Inkscape 0.48.2, OS X Lion
- after ungrouping, the filter effect on the nested group is not rendered until forcing a screen update e.g. by nudging them with the arrow keys (similar to bug #243729)

In 0.48+devel r10956, OS X Lion:
- after ungrouping, the group with the filter effect disappears completely after ungrouping the parent. If nudging the selection immediately after ungrouping, the filtered group is rendered visibly again.

[su_v (suv-lp)]

Also occurs when grouping:

steps to reproduce:
1) draw a shape or path
2) group it
3) blur the group
4) group the blurred group

-> content disappears, and reappears after forcing a screen update (show/hide current layer, or nudge the group with arrow keys up and back down again).

[su_v (suv-lp)]

Related (likely similar underlying issue):

Bug #304407 “After ungrouping or decoupling a clone blur is no longer shown but style attribute still present.”
<https://bugs.launchpad.net/inkscape/+bug/304407> (see steps in comment #3)

Bug #243729 “Grouping filtered text objects looses rendering of filter effects”
<https://bugs.launchpad.net/inkscape/+bug/243729> (see comment #8)

[su_v (suv-lp)]

The old renderer and the initial cairo-based renderer simply did not render the filter effects after grouping/ungrouping.

The disappearing of the objects altogether seems to have been introduced with the initial merge of the rendering cache work in revision 10579 (based on tests with archived builds):
- Not reproduced with r10577
- Reproduced with r10781

[su_v (suv-lp)]

Correction of typo:
- - Reproduced with r10781
+ - Reproduced with r10581

[insaner (insaner)]

seems to also be the case when you cut and then undo.. some filtered objects (tested with text objects -- did not seem to happen to the offset objects in the same cut group) did not immediately reappear (though their bounding boxes were visible)

[Guillermo Espertino (Gez) (gespertino-gmail)]

This happens also with filtered text, just moving it after applying the filter.
- Create a text object
- Apply blur to it.
- move it

The object disappears or a shows incomplete.
Nudging the position seems to fix the problem.

It seems related, so I added this comment here. Please let me know if I should open a new report and add further information about how to reproduce the problem.

[Martin Owens (doctormo)]

OK main bug looks fixed, I've tested everyone's STR with r12528. The disappearing filtered objects because of grouping should be fixed now. Comment #8 is a different but related bug that I fixed in r12525.

[su_v (suv-lp)]

Note: not fixed for clones (see bug summary, see also bug #304407): with current trunk, the clone completely disappears after grouping.

[su_v (suv-lp)]

Clones are fixed in r12648, see bug #304407.