[Posterize] "CRITICAL" console messages when toggling 'Contrasted' live preview

Thanks ~suv!

This filter is currenty in progress, and there are lots of things to improve in the code and UI...

> This filter is currently in progress (…)
I'm aware of the status (it's brand-new and marked as Experimental) ;-) - sorry if this report was overhasty and unneeded.

> - sorry if this report was overhasty and unneeded.

No, no, not at all. I didn't notice this console message... ;)

Not sure this issue is due to the new filter...
The error message triggers after the preview is updated 10 times (just check/uncheck the preview mode, no need to change the default values), when Filter::merge_filters is called in filter.cpp.
Maybe something wrong when reading the filters primitives.
Still investigating.

I don't get the messages with the other filter effects which have dialogs (Drop Shadow, Drop Shadow color, Duochrome custom).

> gboolean sp_document_add_resource(SPDocument*, const gchar*, SPObject*): assertion `!g_slist_find(rlist, object)' failed

Could it be related to using the 'Component Transfer' filter primitive? At least the filter dialog tells:"This SVG filter effect is not yet implemented in Inkscape." and the manual says «Partially implemented, No user interface.».

sp_document_add_resource():
<http://inkscape.modevia.com/doxygen/html/document_8cpp_source.php#l01344>
called from sp_feComponentTransfer_build():
<http://inkscape.modevia.com/doxygen/html/componenttransfer_8cpp_source.php#l00094>
Comment:
     //do we need this?

> Comment: //do we need this?

I don't know, but when it is commented, the filter doesn't trigger the error message anymore.
sp_document_add_resource() is also used in some other filters (pointlight.cpp, distantlight.cpp, spotlight.cpp and componenttransfer-funcnode.cpp) always with the same kind of comment (or // is this necessary?), but in these cases, the ressources are released differently (compare sp_fedistantlight_release with sp_feComponentTransfer_release).

Requesting some help from the dev list...

No idea on how to fix it on the moment.

Fix committed r11679 : Remove the addReource call from feComponentTransfer.

I think JazzyNico's comment #6 is correct.
If a filter primitive explicitly adds a resource it should remove it in the release function.
But it is not necessary to add resources either since the compound filter adds them anyway (and causes the CRITICAL message in this case).

So it should be safe to not add the resource since its not being removed in the release function.
The alternate fix is to remove the added resource in the release function.

FYI - This can be seen in "Effect->Image Paint and Draw->Poster Paint".