| Summary: | RenderBox::backgroundIsKnownToBeOpaqueInRect is wrong for <body> element under certain conditions | ||||||
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| Product: | WebKit | Reporter: | Alok Priyadarshi <alokp> | ||||
| Component: | Layout and Rendering | Assignee: | Alok Priyadarshi <alokp> | ||||
| Status: | RESOLVED FIXED | ||||||
| Severity: | Normal | CC: | jamesr, koivisto, simon.fraser, vangelis | ||||
| Priority: | P2 | ||||||
| Version: | 528+ (Nightly build) | ||||||
| Hardware: | Unspecified | ||||||
| OS: | Unspecified | ||||||
| Bug Depends on: | |||||||
| Bug Blocks: | 70634 | ||||||
| Attachments: |
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I don't see any regression with the test case. Are there some additional steps to reproduce? (In reply to comment #1) > I don't see any regression with the test case. Are there some additional steps to reproduce? I did not find it straightforward to create a "repaint" test case. The attached html page is not really a test case, but rather an example where <body> render-box should not be considered opaque. Please see the latest patch for https://bugs.webkit.org/show_bug.cgi?id=70634. In particular the function skipBodyBackground() and two test cases - body-background-painted and body-background-skipped. Without skipBodyBackground() logic, body-background-skipped will fail. This was fixed in r146531. http://trac.webkit.org/changeset/146531 |
Created attachment 193334 [details] Test case RenderBox::backgroundIsKnownToBeOpaqueInRect looks at the CSS background to determine if the RenderBox is opaque. This works for all elements except the <body> element if: 1. The <body> element is composited 2. The <html> element does not have a background In this case <body> background is not painted and you can see through any elements under the <body>. In the attached example <body> border is painted over the underlying <div>, but the background is not. In this case <body> element is not opaque. As soon as you add a background to the <html> element, the body background gets painted and becomes opaque.