On Thu, 2011-03-31 at 17:00 +0100, Dick Porter wrote: > Hi all > > I've just added a patch to > https://bugzilla.novell.com/show_bug.cgi?id=426305 and am copying it > here too for review. > > It removes the premultiplication when loading PNGs, as no other image > format does the same. It then adds premultiplication when calling > assorted Draw*() functions in image.c, except when the graphics context > is a memory bitmap (so that if an image is drawn onto another image, it > doesn't get premultiplied multiple times.)
>From the little I recall of the issue it makes sense (but will affect performance) to delay the pre-multiplication. The other way would be to keep a flag about the state of each image (and handle saving correctly, i.e. de-multiplication). > I also added a C test case to the bug that demonstrates the various > parts of the problem. > > This patch doesn't break the fix to bug 324503, which introduced the > problem. IIRC there were more than one bug open about this defect so you may get some extra test cases from bugzilla. > OK to commit? I'll let the new MWF maintainers answer that :-) since I do not run any code that use libgdiplus (or System.Drawing) very often so, unlike many, I won't be affected, either positively or negatively ;-) Thanks Sebastien _______________________________________________ Mono-winforms-list maillist - [email protected] http://lists.ximian.com/mailman/listinfo/mono-winforms-list
