250882 2023-01-19 17:49:38 -0800 BackgroundPainter::paintFillLayers should check box-shadow when finding an opaque layer. 2024-03-06 02:10:08 -0800 1 1 1 Unclassified WebKit Layout and Rendering WebKit Nightly Build Unspecified Unspecified RESOLVED FIXED BrowserCompat, InRadar P2 Normal --- 1 ahmad.saleem792 webkit-unassigned bfulgham karlcow koivisto ntim simon.fraser webkit-bug-importer zalan oldest_to_newest 1926783 0 ahmad.saleem792 2023-01-19 17:49:38 -0800 Hi Team, While going through Blink's commit, I came across another failing test case in Safari 16.2 and STP161: Test Case - https://jsfiddle.net/hL9bj0q7/show ^ It does not have any shadow in Safari but does in Chrome Canary 111 and Firefox Nightly 111. Blink Commit - https://chromium.googlesource.com/chromium/blink/+/a48f4540763c24adff42b9b77d719597f51482f6 WebKit Source - https://searchfox.org/wubkat/source/Source/WebCore/rendering/BackgroundPainter.cpp#131 Need to add below or equivalent: !boxShadowShouldBeAppliedToBackground(bleedAvoidance) OR !boxShadowShouldBeAppliedToBackground(m_renderer, paintRect.location(), bleedAvoidance, { }) ____ Just wanted to raise so we can fix it. Thanks! 1926806 1 karlcow 2023-01-19 20:43:19 -0800 There is a FIXME in the source code. https://searchfox.org/wubkat/rev/5b1acc527ab5b10c9d9e4dd21fcec68e315790c2/Source/WebCore/rendering/BackgroundPainter.cpp#122-132 And the code was last edited by antti but the FIXME predates this Adding occlusion detection to reduce overdraw in RenderBox background rendering Justin Novosad, Fri, 23 Nov 2012 18:43:51 +0000 added in https://searchfox.org/wubkat/commit/71cbe979b543bafb933abdd82a03d72df95c7e0e // Stop traversal when an opaque layer is encountered. // FIXME: It would be possible for the following occlusion culling test to be more aggressive // on layers with no repeat by testing whether the image covers the layout rect. // Testing that here would imply duplicating a lot of calculations that are currently done in // BackgroundPainter::paintFillLayer. A more efficient solution might be to move // the layer recursion into paintFillLayer, or to compute the layer geometry here // and pass it down. // The clipOccludesNextLayers condition must be evaluated first to avoid short-circuiting. if (layer->clipOccludesNextLayers(layer == &fillLayer) && layer->hasOpaqueImage(m_renderer) && layer->image()->canRender(&m_renderer, m_renderer.style().effectiveZoom()) && layer->hasRepeatXY() && layer->blendMode() == BlendMode::Normal) break; 1928772 2 webkit-bug-importer 2023-01-26 17:50:17 -0800 <rdar://problem/104722307> 2018501 3 ahmad.saleem792 2024-03-04 11:12:54 -0800 This compiles and fixes the bug: && !boxShadowShouldBeAppliedToBackground(m_renderer, rect.location(), bleedAvoidance, { }) ___ Just wanted to share. (Draft) PR - https://github.com/WebKit/WebKit/pull/25436 2019028 4 ews-feeder 2024-03-06 02:10:05 -0800 Committed 275735@main (b6231f750f4e): <https://commits.webkit.org/275735@main> Reviewed commits have been landed. Closing PR #25436 and removing active labels.