Video with object-fit: cover can spill outside the box

• Component: Layout and Rendering
• Status: RESOLVED FIXED

[Simon Fraser (smfr)]

Follow-on from bug 52040 :
With object-fit: cover, <video> may spill outside the box, and we don't have a layer we can set masksToBounds on to clip it.

[Simon Pieters (:zcorpan)]

object-fit:cover is supposed to spill outside the box when overflow:visible. No?

[Simon Fraser (smfr)]

So says the spec (not that I agree with it). But with overflow:hidden we'll have to fix this anyway.

[Simon Pieters (:zcorpan)]

We have the opposite problem in Opera, <video> is always clipped. However we could always change the spec to say that the content is always clipped regardless of 'overflow' if people think overflowing is useless/annoying.

[Simon Pieters (:zcorpan)]

...though maybe that ship has sailed for SVG content anyway.

[Simon Fraser (smfr)]

I think authors would not expect overflow for elements like <img> and <video>.

[Simon Pieters (:zcorpan)]

We could add overflow:hidden to the UA style sheet for those elements, maybe?

[Simon Pieters (:zcorpan)]

(spec bug http://www.w3.org/Bugs/Public/show_bug.cgi?id=11746 )

[Simon Fraser (smfr)]

Created attachment 210173 [details]
Patch

[WebKit Commit Bot]

Attachment 210173 [details] did not pass style-queue:

Failed to run "['Tools/Scripts/check-webkit-style', '--diff-files', u'LayoutTests/ChangeLog', u'LayoutTests/compositing/images/direct-image-object-fit-expected.txt', u'LayoutTests/compositing/images/direct-image-object-fit.html', u'LayoutTests/compositing/reflections/direct-image-object-fit-reflected-expected.txt', u'LayoutTests/compositing/reflections/direct-image-object-fit-reflected.html', u'LayoutTests/compositing/video/video-object-fit-expected.txt', u'LayoutTests/compositing/video/video-object-fit.html', u'LayoutTests/platform/mac/compositing/images/direct-image-object-fit-expected.txt', u'LayoutTests/platform/mac/compositing/reflections/direct-image-object-fit-reflected-expected.txt', u'LayoutTests/platform/mac/compositing/video/video-object-fit-expected.txt', u'Source/WebCore/ChangeLog', u'Source/WebCore/page/Frame.h', u'Source/WebCore/platform/graphics/GraphicsLayer.h', u'Source/WebCore/platform/graphics/MediaPlayer.cpp', u'Source/WebCore/platform/graphics/MediaPlayer.h', u'Source/WebCore/platform/graphics/MediaPlayerPrivate.h', u'Source/WebCore/platform/graphics/avfoundation/MediaPlayerPrivateAVFoundation.cpp', u'Source/WebCore/platform/graphics/avfoundation/MediaPlayerPrivateAVFoundation.h', u'Source/WebCore/platform/graphics/avfoundation/cf/MediaPlayerPrivateAVFoundationCF.cpp', u'Source/WebCore/platform/graphics/avfoundation/cf/MediaPlayerPrivateAVFoundationCF.h', u'Source/WebCore/platform/graphics/avfoundation/objc/MediaPlayerPrivateAVFoundationObjC.h', u'Source/WebCore/platform/graphics/avfoundation/objc/MediaPlayerPrivateAVFoundationObjC.mm', u'Source/WebCore/platform/graphics/ca/GraphicsLayerCA.cpp', u'Source/WebCore/platform/graphics/ca/GraphicsLayerCA.h', u'Source/WebCore/rendering/RenderLayerBacking.cpp', u'Source/WebCore/rendering/RenderLayerCompositor.cpp', u'Source/WebCore/rendering/RenderVideo.cpp', u'Source/WebCore/testing/Internals.cpp', u'Source/WebCore/testing/Internals.h', u'Source/WebCore/testing/Internals.idl']" exit_code: 1
Source/WebCore/testing/Internals.h:228:  enum members should use InterCaps with an initial capital letter.  [readability/enum_casing] [4]
Source/WebCore/testing/Internals.h:229:  enum members should use InterCaps with an initial capital letter.  [readability/enum_casing] [4]
Total errors found: 2 in 30 files


If any of these errors are false positives, please file a bug against check-webkit-style.

[Simon Fraser (smfr)]

Created attachment 210175 [details]
Patch

[WebKit Commit Bot]

Attachment 210175 [details] did not pass style-queue:

Failed to run "['Tools/Scripts/check-webkit-style', '--diff-files', u'LayoutTests/ChangeLog', u'LayoutTests/compositing/images/direct-image-object-fit-expected.txt', u'LayoutTests/compositing/images/direct-image-object-fit.html', u'LayoutTests/compositing/reflections/direct-image-object-fit-reflected-expected.txt', u'LayoutTests/compositing/reflections/direct-image-object-fit-reflected.html', u'LayoutTests/compositing/video/video-object-fit-expected.txt', u'LayoutTests/compositing/video/video-object-fit.html', u'LayoutTests/media/video-object-fit-change.html', u'LayoutTests/platform/mac/TestExpectations', u'LayoutTests/platform/mac/compositing/images/direct-image-object-fit-expected.txt', u'LayoutTests/platform/mac/compositing/reflections/direct-image-object-fit-reflected-expected.txt', u'LayoutTests/platform/mac/compositing/video/video-object-fit-expected.txt', u'Source/WebCore/ChangeLog', u'Source/WebCore/page/Frame.h', u'Source/WebCore/platform/graphics/GraphicsLayer.h', u'Source/WebCore/platform/graphics/MediaPlayer.cpp', u'Source/WebCore/platform/graphics/MediaPlayer.h', u'Source/WebCore/platform/graphics/MediaPlayerPrivate.h', u'Source/WebCore/platform/graphics/avfoundation/MediaPlayerPrivateAVFoundation.cpp', u'Source/WebCore/platform/graphics/avfoundation/MediaPlayerPrivateAVFoundation.h', u'Source/WebCore/platform/graphics/avfoundation/cf/MediaPlayerPrivateAVFoundationCF.cpp', u'Source/WebCore/platform/graphics/avfoundation/cf/MediaPlayerPrivateAVFoundationCF.h', u'Source/WebCore/platform/graphics/avfoundation/objc/MediaPlayerPrivateAVFoundationObjC.h', u'Source/WebCore/platform/graphics/avfoundation/objc/MediaPlayerPrivateAVFoundationObjC.mm', u'Source/WebCore/platform/graphics/ca/GraphicsLayerCA.cpp', u'Source/WebCore/platform/graphics/ca/GraphicsLayerCA.h', u'Source/WebCore/rendering/RenderLayerBacking.cpp', u'Source/WebCore/rendering/RenderLayerCompositor.cpp', u'Source/WebCore/rendering/RenderVideo.cpp', u'Source/WebCore/testing/Internals.cpp', u'Source/WebCore/testing/Internals.h', u'Source/WebCore/testing/Internals.idl']" exit_code: 1
Source/WebCore/testing/Internals.h:228:  enum members should use InterCaps with an initial capital letter.  [readability/enum_casing] [4]
Source/WebCore/testing/Internals.h:229:  enum members should use InterCaps with an initial capital letter.  [readability/enum_casing] [4]
Total errors found: 2 in 31 files


If any of these errors are false positives, please file a bug against check-webkit-style.

[Dean Jackson]

Comment on attachment 210175 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=210175&action=review

> Source/WebCore/platform/graphics/ca/GraphicsLayerCA.cpp:1797
> +    bool needContentsClippingLayer = !m_contentsClippingRect.contains(m_contentsRect);
> +    bool gainedOrLostClippingLayer = false;
> +    if (needContentsClippingLayer) {

You don't need needContentsClippingLayer.

> LayoutTests/compositing/video/video-object-fit.html:52
> +            }, 1500);

1.5s :(

[Simon Fraser (smfr)]

https://trac.webkit.org/r154921