94246 2012-08-16 13:30:52 -0700 [Chromium] Uint8ClampedArray fast path rounds incorrectly 2012-09-19 00:10:50 -0700 1 1 1 Unclassified WebKit WebGL 528+ (Nightly build) Unspecified Unspecified RESOLVED FIXED P2 Normal --- 1 d-r ulan abarth code.vineet danno dpranke kbr ulan zmo oldest_to_newest 697442 0 d-r 2012-08-16 13:30:52 -0700 When analysing two philip canvas tests I found that the ArrayBuffer bindings in Chromium have a fast path (ExternalArray) using ArrayBuffer's baseAddress to set indexed properties directly. This fast path does not use the same rounding (round to nearest, even in halfway case, equivalent to lrint()) that was put in place now for Uint8ClampedArray::set in order to adhere to the spec. For 2d.imageData.object.round.html to pass on Chromium, this needs to be fixed. More info in bug 40272. 697657 1 kbr 2012-08-16 16:31:56 -0700 Could you please provide a test case which demonstrates the problem? 697714 2 abarth 2012-08-16 17:20:29 -0700 There's a test case in bug 40272 that Chromium fails. 697726 3 kbr 2012-08-16 17:31:26 -0700 Filed V8 bug https://code.google.com/p/v8/issues/detail?id=2294 to track this. 701965 4 ulan 2012-08-22 08:44:18 -0700 The V8 bug is fixed. I will adjust canvas test expectations after V8 rolls in Chromium. 702269 5 kbr 2012-08-22 13:26:13 -0700 (In reply to comment #4) > The V8 bug is fixed. I will adjust canvas test expectations after V8 rolls in Chromium. Ulan, thanks for fixing this. Note that array-unit-tests.html was just updated in the Khronos WebGL github repo, so do you think you could pull in a revised version of this test and its expectations too? 703852 6 ulan 2012-08-24 00:37:22 -0700 > Note that array-unit-tests.html was just updated in the Khronos WebGL github repo, so do you think you could pull in a revised version of this test and its expectations too? Yep, I can update the tests. But it looks like zmo@ is already taking care of this? 704273 7 kbr 2012-08-24 11:28:46 -0700 zmo@ updated the tests in the Khronos repo, but it would be great to pull the revised tests from the Khronos repo back into the WebKit repo as a layout test. 705317 8 d-r 2012-08-27 09:17:01 -0700 In Bug 40272 Benjamin requested a better fallback implementation for MSVC & !X86 - you might want to take a look and do something similar in V8. 723136 9 dpranke 2012-09-18 17:11:56 -0700 it looks like the following layout tests that were listed as relevant to this bug are no longer failing. BUGWK94246 : canvas/philip/tests/2d.imageData.object.round.html = TEXT BUGWK94246 : platform/chromium/virtual/gpu/canvas/philip/tests/2d.imageData.object.round.html = TEXT BUGWK94246 : fast/canvas/canvas-ImageData-behaviour.html = TEXT BUGWK94246 : platform/chromium/virtual/gpu/fast/canvas/canvas-ImageData-behaviour.html = TEXT So I've removed the suppressions in http://trac.webkit.org/changeset/128945 . Can we now close this? It looks that way from what I can glean from the comments. 723336 10 ulan 2012-09-19 00:10:50 -0700 > Can we now close this? It looks that way from what I can glean from the comments. Yes, V8 with the fix rolled in Chrome.