W dniu 23 czerwca 2011 14:10 użytkownik Chris Morgan <chris.morganiser@...400...> napisał:
It is even as I feared and expected. This Cairo renderer breaks filters which use the BackgroundImage source even more than they were already
I didn't put much effort into implementing correct BackgroundImage handling yet. The semantics of BackgroundImage make absolutely no sense for meat the moment. For example, background accumulation has to be explicitly enabled (there seems to be no UI for setting this besides the XML editor), and objects are rendered onto the background without filters. I got it only to the point where blend modes and other per-pixel filters worked correctly.
I can also say that "average quality" rendering of Gaussian blurs with high levels of blur looks far worse than it used to (though it's definitely faster).
I would be interested in getting a screenshot comparison. It might be related to the fact that Cairo does not properly downscale images at the moment (no supersampling).
I can see this sort of thing becoming a bit of a headache in dealing with rendering bugs when different versions of Cairo are used. Things will be much less dependent only upon Inkscape.
Filter rendering is not dependent on Cairo in any way. Only the downscaling / upscaling is, when rendering at less than 100% quality. The BackgroundImage bugs are entirely on Inkscape's side, and almost all of the problems you are seeing are due to incorrect calculation of the background area required by the filter.
Regards, Krzysztof