245416 2022-09-20 01:27:52 -0700 [LBSE] Pixel snapping logic is incorrect for SVG, when elements are composited 2022-09-26 08:52:21 -0700 1 1 1 Unclassified WebKit SVG WebKit Local Build Unspecified Unspecified RESOLVED FIXED InRadar P2 Normal --- 90738 1 zimmermann zimmermann rbuis sabouhallawa webkit-bug-importer zimmermann oldest_to_newest 1899751 0 zimmermann 2022-09-20 01:27:52 -0700 In bug webkit.org/b/244966 ("[LBSE] Outermost <svg> elements are not device-pixel aligned") the rendering was adapted in such a way that the outermost <svg> element is the only element in the SVG subtree that is pixel snapped, delivering consistent results between e.g. HTML <div> elements and SVG <svg> elements, embedded in a CSS formatting context. The <div> will get pixel snapped upon painting -- the same was enforced for the outermost <svg>, however without propagating/accumulating sub-pixel errors for the descendant layers, since no pixel snapping is applied within the SVG subtree. When elements are composited another logic is used (RenderLayerBacking), and the device-pixel alignment is applied for all SVG layers -- effectively breaking content. By fixing that, the pixel snapping logic is consistent for all painting modes we have, no matter if the outer <svg> is composited, or any of its descendants. 1899757 1 zimmermann 2022-09-20 02:01:53 -0700 Pull request: https://github.com/WebKit/WebKit/pull/4520 1901194 2 ews-feeder 2022-09-26 08:51:16 -0700 Committed 254863@main (d2c0299eb83a): <https://commits.webkit.org/254863@main> Reviewed commits have been landed. Closing PR #4520 and removing active labels. 1901195 3 webkit-bug-importer 2022-09-26 08:52:21 -0700 <rdar://problem/100412807>