On Wednesday, April 20, 2016 at 5:44:14 AM UTC-4, [email protected] wrote: > I've tried increasing the dimensions of aDirtyRegion when calling > nsLayoutUtils::PaintFrame() from nsPresShell.cpp. > https://dxr.mozilla.org/mozilla-central/source/layout/base/nsPresShell.cpp#6351 > That didn't seem to make a difference.
I haven't tested this, but I'll try to point you in the right direction. The place to start looking is probably this line in nsGfxScrollFrame::BuildDisplayList() [1] where we restrict the dirty rect (which is essentially the rect that needs to be repainted) to the scroll frame's "scroll port". For the page's root scroll frame, that's the viewport. You may want to condition any modification you make to this line, to the scroll frame being the page's root scroll frame. The condition to test this is something like |mIsRoot && mOuter->PresContext()->IsRootContentDocument()|. (|mIsRoot| is true for the root scroll frame of any document, including an iframe. |IsRootContentDocument()| is only true for the top-level page you're viewing). If you're using APZ (async panning/zooming; it's the default in e10s mode on 46 and newer), you probably also want to adjust this line [2] which overwrites the dirty rect to be the "display port", which is an area larger than the scroll port that we pre-render so async panning can bring it into view without repainting, but still not (necessarily) as large as the entire document. There may also be other places that need to be adjusted that I'm not aware of or not thinking of right now. This probably goes without saying, but rendering the entire document will kill performance for large documents, so it's suitable for debugging only (I assume that's what you have in mind). Hope that helps! Cheers, Botond [1] https://dxr.mozilla.org/mozilla-central/rev/ae7413abfa4d3954a6a4ce7c1613a7100f367f9a/layout/generic/nsGfxScrollFrame.cpp#3145 [2] https://dxr.mozilla.org/mozilla-central/rev/ae7413abfa4d3954a6a4ce7c1613a7100f367f9a/layout/generic/nsGfxScrollFrame.cpp#3512 _______________________________________________ dev-tech-layout mailing list [email protected] https://lists.mozilla.org/listinfo/dev-tech-layout
