139956 2014-12-26 11:44:12 -0800 Vertical % or viewport sized units render a bit too small 2023-07-03 06:39:37 -0700 1 1 1 Unclassified WebKit Layout and Rendering 525.x (Safari 3.2) Unspecified Unspecified RESOLVED CONFIGURATION CHANGED P2 Normal --- 132010 1 davideads webkit-unassigned ahmad.saleem792 benjamin zalan oldest_to_newest 1057917 0 davideads 2014-12-26 11:44:12 -0800 Hopefully I can describe this effectively: For a recent project I made a stacked bar chart using pure CSS and percentage units. Each section of the bar has a percentage based height. All the sections heights add up to 100%. However, unless the container height is such that the percentage based heights map to an exact integer pixel size (e.g. 9% of 500px is 45px, but 9% of 380px is 34.199px), the total height of the boxes is consistently less than the total height of the container. I made a demo: http://apps.npr.org/lookatthis/posts/publichousing-webkit-bug-demo/ (actual in-the-wild project here: http://apps.npr.org/lookatthis/posts/publichousing) The percent heights add up to 100%, but the boxes themselves occupy a few pixels less than 100%. The same behavior can be seen using viewport-relative units like vh. I was able to replicate in Safari (OS X, iOS) and Chrome (on OS X, Android, iOS). It doesn't show up in Firefox. 1057921 1 benjamin 2014-12-26 13:28:17 -0800 It looks like percent sizes do not get subpixel layout. There is a block of 380px split in 33%, 33%, 34%. The computed size of each block is 125px, 125px, 129px. It should ideally be 125.4, 124.4px, 129.2px. Zalan would know why we don't get subpixel layout in that case. 1057957 2 243775 zalan 2014-12-26 21:57:01 -0800 Created attachment 243775 Test reduction. 1964713 3 ahmad.saleem792 2023-07-02 16:08:02 -0700 I am not able to reproduce this bug using attached test reduction on STP173 and it matches Chrome Canary 117. @Alan - I think we can close this, appreciate if you can confirm. 243775 2014-12-26 21:57:01 -0800 2014-12-26 21:57:01 -0800 Test reduction. table-div.html text/html 929 zalan PGh0bWw+CjxzdHlsZT4KLmNvbnRhaW5lcnsKICBoZWlnaHQ6IDEwMnB4OyAKICBib3JkZXI6IDJw eCBzb2xpZCBibGFjazsKfQouaW5uZXJ7CiAgZGlzcGxheTogdGFibGU7CiAgd2lkdGg6IDEwMCU7 Cn0KCi5jZWxsMXsKICBiYWNrZ3JvdW5kLWNvbG9yOiByZWQ7CiAgZGlzcGxheTogdGFibGUtY2Vs bDsKfQoKLmNlbGwyewogIGJhY2tncm91bmQtY29sb3I6IGdyZWVuOwogIGRpc3BsYXk6IHRhYmxl LWNlbGw7Cn0KCi5jZWxsM3sKICBiYWNrZ3JvdW5kLWNvbG9yOiBibHVlOwogIGRpc3BsYXk6IHRh YmxlLWNlbGw7Cn0KCjwvc3R5bGU+Cjxib2R5Pgo8YnI+d2l0aCB0YWJsZXMgKDMzJSwgMzMlLCAz NCUpIC1ub3RpY2UgdGhlIHBpeGVsIGdhcCBhdCB0aGUgYm90dG9tIG9mIHRoZSBsYXN0IHRhYmxl Lgo8ZGl2IGNsYXNzPSJjb250YWluZXIiPgogIDxkaXYgY2xhc3M9ImlubmVyIiBzdHlsZT0iaGVp Z2h0OiAzMyU7Ij4KICAgIDxkaXYgY2xhc3M9ImNlbGwxIj48L2Rpdj4KICA8L2Rpdj4KICA8ZGl2 IGNsYXNzPSJpbm5lciIgc3R5bGU9ImhlaWdodDogMzMlOyI+CiAgICAgIDxkaXYgY2xhc3M9ImNl bGwyCSI+PC9kaXY+CiAgICA8L2Rpdj4KICAgIDxkaXYgY2xhc3M9ImlubmVyIiBzdHlsZT0iaGVp Z2h0OiAzNCU7Ij4KICAgICAgPGRpdiBjbGFzcz0iY2VsbDMiPjwvZGl2PgogICAgPC9kaXY+Cgo8 YnI+d2l0aCBkaXZzICgzMyUsIDMzJSwgMzQlKQo8ZGl2IGNsYXNzPSJjb250YWluZXIiPgogIDxk aXYgc3R5bGU9ImhlaWdodDogMzMlOyBiYWNrZ3JvdW5kLWNvbG9yOiByZWQiPjwvZGl2PgogIDxk aXYgc3R5bGU9ImhlaWdodDogMzMlOyBiYWNrZ3JvdW5kLWNvbG9yOiBncmVlbiI+PC9kaXY+CiAg PGRpdiBzdHlsZT0iaGVpZ2h0OiAzNCU7IGJhY2tncm91bmQtY29sb3I6IGJsdWUiPjwvZGl2Pgog ICAgPC9kaXY+CjwvZGl2Pgo=