On a page like http://smfr.org/misc/four-bars-shadows.html, if you zoom in and pan around, bits of the bars are sometimes missing. This happens when they get into tiled mode, but we fail to update the tiles during scrolling. This is related to https://trac.webkit.org/changeset/186155.
Created attachment 295023 [details] Patch
<rdar://problem/29303891>
<rdar://problem/29303889>
Created attachment 295024 [details] Patch
Created attachment 295030 [details] Patch
Comment on attachment 295030 [details] Patch Attachment 295030 [details] did not pass ios-sim-ews (ios-simulator-wk2): Output: http://webkit-queues.webkit.org/results/2529833 New failing tests: scrollingcoordinator/ios/sync-layer-positions-after-scroll.html
Created attachment 295036 [details] Archive of layout-test-results from ews125 for ios-simulator-wk2 The attached test failures were seen while running run-webkit-tests on the ios-sim-ews. Bot: ews125 Port: ios-simulator-wk2 Platform: Mac OS X 10.11.6
Comment on attachment 295030 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=295030&action=review > Source/WebCore/platform/graphics/GraphicsLayer.h:605 > + // If set, overrides m_position. Only used for coverage computation. > + Optional<FloatPoint> m_approximatePosition; This could use a slightly more in depth comment, as the term approximate is a bit scary.
Some test infrastructure in bug 164905.
https://trac.webkit.org/changeset/208927