53695 2011-02-03 11:00:28 -0800 Style transform (-webkit-transform: scale3d) with 0-scale renders, but disables mouse events. 2024-05-27 10:39:27 -0700 1 1 1 Unclassified WebKit CSS 528+ (Nightly build) All All NEW https://bugs.webkit.org/show_bug.cgi?id=237470 https://bugs.webkit.org/show_bug.cgi?id=274654 InRadar P2 Normal --- 1 wjmaclean webkit-unassigned bfulgham bugs cmarrin dino simon.fraser tetsuharu.ohzeki webkit-bug-importer oldest_to_newest 344849 0 wjmaclean 2011-02-03 11:00:28 -0800 Visit the attached HTML file scale0.html with Chromium/Safari, both with gpu enabled and not enabled. The box labelled "broken" has a style element "-webkit-transform: scale3d(0.8,0.8,0)" that is applied when the box is clicked. Two different behaviours are seen, depending on whether GPU acceleration is enabled in the browser or not. With GPU enabled, clicking on the box labelled "broken" changes the DIV's transform in a way that makes it non-invertible, causing it to be subsequently is removed from hit-testing. After the initial click this element no longer receives mouse events. With GPU disabled, clicking on the same box appears to work normally, partially because in non-gpu mode WebKit calls makeRenderable() which overrides the element's transform by making it affine (and in the process invertible). In both cases though the element is rendered. According to the CSS specs (http://www.w3.org/TR/css3-2d-transforms/), elements with non-invertible transforms should not be rendered: "In some cases, an animation might cause a transformation matrix to be singular or non-invertible. For example, an animation in which scale moves from 1 to -1. At the time when the matrix is in such a state, the transformed element is not rendered." This suggests that perhaps the correct behaviour would be to not render the element at all. In any case, it seems desirable that both code paths should produce the same result. 344850 1 81087 wjmaclean 2011-02-03 11:01:21 -0800 Created attachment 81087 Test case with style containing 0-scale. 344875 2 dino 2011-02-03 11:31:20 -0800 Seems like we need to decide things like: - does scale to 0 along any axis make something disappear? - does scale to 0 along any axis make something invisible to events? - should a Z scale do anything to a 2d-only scene? - what should happen with rotateY(90deg) scale(0, 1) rotateY(-90deg)? ie. if you scale to 0 along an axis perpendicular to the plane you exist in, does that make you disappear? 903412 3 bugs 2013-06-25 12:59:25 -0700 Per spec, this should not be rendered at all: http://www.w3.org/TR/css3-transforms/#transform-function-lists 1882560 4 bfulgham 2022-07-12 14:18:59 -0700 Firefox and Chrome agree on behavior. Safari fails. 1882561 5 webkit-bug-importer 2022-07-12 14:19:10 -0700 <rdar://problem/96910006> 81087 2011-02-03 11:01:21 -0800 2011-02-03 11:01:21 -0800 Test case with style containing 0-scale. scale0.html text/html 1235 wjmaclean PCFET0NUWVBFIGh0bWw+CjxodG1sPgo8aGVhZD4KICA8bWV0YSBjaGFyc2V0PSJ1dGYtOCI+CiAg PHRpdGxlPlRlc3QgZm9yIG1vdXNldXAgaXNzdWU8L3RpdGxlPgogIDxzdHlsZSB0eXBlPSJ0ZXh0 L2NzcyI+CiAgICBkaXYgewogICAgICB3aWR0aDoyMDBweDsKICAgICAgaGVpZ2h0OjIwMHB4OyAg ICAgIAogICAgICBiYWNrZ3JvdW5kLWNvbG9yOiBibHVlOwogICAgICBtYXJnaW46MjBweDsKICAg ICAgdGV4dC1hbGlnbjpjZW50ZXI7CiAgICAgIGNvbG9yOiB3aGl0ZTsKICAgIH0KICAgICN3b3Jr cy5kb3duIHsKICAgICAgYmFja2dyb3VuZC1jb2xvcjogcmVkOwogICAgICAtd2Via2l0LXRyYW5z Zm9ybTogc2NhbGUzZCgwLjgsMC44LDEpOyAKICAgIH0KICAgICNicm9rZW4uZG93biB7CiAgICAg IGJhY2tncm91bmQtY29sb3I6IHJlZDsKICAgICAgLXdlYmtpdC10cmFuc2Zvcm06IHNjYWxlM2Qo MC44LDAuOCwwLjApOyAKICAgIH0KICA8L3N0eWxlPgo8L2hlYWQ+Cjxib2R5PgogIDxkaXYgaWQ9 IndvcmtzIj4KICAgIFdvcmtzCiAgPC9kaXY+CiAgPGRpdiBpZD0iYnJva2VuIj4KICAgIEJyb2tl bgogIDwvZGl2PgogIDxzY3JpcHQgdHlwZT0idGV4dC9qYXZhc2NyaXB0Ij4KICAgIGZ1bmN0aW9u IG9uRG93bihlKQogICAgewogICAgICBsb2dldmVudChlKTsKICAgICAgZS50YXJnZXQuY2xhc3NO YW1lPSdkb3duJzsKICAgIH0KICAgIGZ1bmN0aW9uIG9uVXAoZSkKICAgIHsKICAgICAgbG9nZXZl bnQoZSk7CiAgICAgIGUudGFyZ2V0LmNsYXNzTmFtZT0nJzsKICAgIH0KICAgIGZ1bmN0aW9uIGxv Z2V2ZW50KGUpCiAgICB7CiAgICAgIGNvbnNvbGUubG9nKGUudHlwZSArICcgb24gJysgZS50YXJn ZXQuaWQpOwogICAgfQogICAgdmFyIGRpdnMgPSBkb2N1bWVudC5xdWVyeVNlbGVjdG9yQWxsKCdk aXYnKTsKICAgIGZvcih2YXIgaSA9IDA7IGkgPCBkaXZzLmxlbmd0aDsgaSsrKSB7CiAgICAgIGRp dnNbaV0uYWRkRXZlbnRMaXN0ZW5lcignbW91c2Vkb3duJywgb25Eb3duLCBmYWxzZSk7CiAgICAg IGRpdnNbaV0uYWRkRXZlbnRMaXN0ZW5lcignbW91c2V1cCcsIG9uVXAsIGZhbHNlKTsKICAgICAg ZGl2c1tpXS5hZGRFdmVudExpc3RlbmVyKCdtb3VzZW92ZXInLCBsb2dldmVudCwgZmFsc2UpOwog ICAgICBkaXZzW2ldLmFkZEV2ZW50TGlzdGVuZXIoJ21vdXNlb3V0JywgbG9nZXZlbnQsIGZhbHNl KTsKICAgIH0KICA8L3NjcmlwdD4KPC9ib2R5Pgo8L2h0bWw+Cgo=