139412 2014-12-08 13:36:09 -0800 SVG chained filter effects clip out-of-region drawing incorrectly 2026-02-14 14:50:53 -0800 1 1 1 Unclassified WebKit SVG 528+ (Nightly build) Unspecified Unspecified NEW BrowserCompat, InRadar P2 Normal --- 1 sabouhallawa webkit-unassigned ahmad.saleem792 krit mcatanzaro webkit-bug-importer zimmermann oldest_to_newest 1053499 0 242844 sabouhallawa 2014-12-08 13:36:09 -0800 Created attachment 242844 Test case Open the following SVG in WebKit: <svg xmlns="http://www.w3.org/2000/svg"> <filter id="f1" x="0" y="0" width="100" height="100" filterUnits="userSpaceOnUse"> <!-- Create a green square at x=0. --> <feFlood result="red" x="100" y="0" flood-color="red"/> <feFlood result="green" flood-color="green"/> <!-- Attempt to offset the red square left to cover up the green square. However, this filter's filter region should clip away the red square, and only transparent pixels should be offset left, leaving the green square intact. --> <feOffset result="red" in="SourceGraphic" dx="-100" x="0" y="0" width="200" height="100"/> <feMerge> <feMergeNode in="green"/> <feMergeNode in="red"/> </feMerge> </filter> <rect x="0" y="0" width="100" height="100" filter="url(#f1)"/> </svg> Result: Nothing is drawn. Expected: A 100 x 100 green rectangle. A black rectangle is drawn at (0,0). The filter f1 has a red rectangle drawn at (100,0). This rectangle should be completely clipped since it outside the rectangle area of the target element. When offsetting this rectangle with dx=-1, this should not have any effect because it clipped when it was first drawn. Merging this empty rectangle with a green rectangle should result in a green rectangle at (0,0) NOTE: FireFox and Chrome both render this SVG as expected. NOTE: This test is an imported test from Mozilla SVG test suite but is modified a little to narrow down the problem. 1053501 1 webkit-bug-importer 2014-12-08 13:36:54 -0800 <rdar://problem/19180719> 1053502 2 krit 2014-12-08 13:37:20 -0800 IIRC there is a dupe for this one already. 1213927 3 mcatanzaro 2016-07-23 11:00:23 -0700 These tests are flaky (sometimes pass) on GTK, passing more often now that we've enabled threaded compositor. Updating expectations accordingly. 1905953 4 ahmad.saleem792 2022-10-16 04:43:42 -0700 I am able to reproduce this bug in Safari Technology Preview 155 as well, where nothing is draw while both Chrome Canary 108 and Firefox Nightly 107 have "green" square. Thanks! 1953617 5 ahmad.saleem792 2023-05-08 02:28:09 -0700 (In reply to Ahmad Saleem from comment #4) > I am able to reproduce this bug in Safari Technology Preview 155 as well, > where nothing is draw while both Chrome Canary 108 and Firefox Nightly 107 > have "green" square. Thanks! With LBSE turned on using WebKit ToT (minibrowser), it does show 'black' rectangle compared to 'green' of other browsers. So LBSE slightly progresses this. 242844 2014-12-08 13:36:09 -0800 2014-12-08 13:36:09 -0800 Test case clip-input.svg image/svg+xml 858 sabouhallawa PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciPgogICAgPGZpbHRlciBpZD0i ZjEiIHg9IjAiIHk9IjAiIHdpZHRoPSIxMDAiIGhlaWdodD0iMTAwIiBmaWx0ZXJVbml0cz0idXNl clNwYWNlT25Vc2UiPgogICAgICA8IS0tIENyZWF0ZSBhIGdyZWVuIHNxdWFyZSBhdCB4PTAuIC0t PgogICAgICA8ZmVGbG9vZCByZXN1bHQ9InJlZCIgeD0iMTAwIiB5PSIwIiBmbG9vZC1jb2xvcj0i cmVkIi8+CiAgICAgIDxmZUZsb29kIHJlc3VsdD0iZ3JlZW4iIGZsb29kLWNvbG9yPSJncmVlbiIv PgogICAgICA8IS0tCiAgICAgICAgICBBdHRlbXB0IHRvIG9mZnNldCB0aGUgcmVkIHNxdWFyZSBs ZWZ0IHRvIGNvdmVyIHVwIHRoZSBncmVlbiBzcXVhcmUuCiAgICAgICAgICBIb3dldmVyLCB0aGlz IGZpbHRlcidzIGZpbHRlciByZWdpb24gc2hvdWxkIGNsaXAgYXdheSB0aGUgcmVkIHNxdWFyZSwK ICAgICAgICAgIGFuZCBvbmx5IHRyYW5zcGFyZW50IHBpeGVscyBzaG91bGQgYmUgb2Zmc2V0IGxl ZnQsIGxlYXZpbmcgdGhlIGdyZWVuCiAgICAgICAgICBzcXVhcmUgaW50YWN0LgogICAgICAtLT4K ICAgICAgPGZlT2Zmc2V0IHJlc3VsdD0icmVkIiBpbj0iU291cmNlR3JhcGhpYyIgZHg9Ii0xMDAi IHg9IjAiIHk9IjAiIHdpZHRoPSIyMDAiIGhlaWdodD0iMTAwIi8+CiAgICAgIDxmZU1lcmdlPgog ICAgICAgICAgPGZlTWVyZ2VOb2RlIGluPSJncmVlbiIvPgogICAgICAgICAgPGZlTWVyZ2VOb2Rl IGluPSJyZWQiLz4KICAgICAgPC9mZU1lcmdlPgogICAgPC9maWx0ZXI+CiAgICA8cmVjdCB4PSIw IiB5PSIwIiB3aWR0aD0iMTAwIiBoZWlnaHQ9IjEwMCIgZmlsdGVyPSJ1cmwoI2YxKSIvPgo8L3N2 Zz4K