Bug 218910

Summary: Value of animation at time 0 does not match Firefox (or WPT test expectations) for color accumulate composite test
Product: WebKit Reporter: Sam Weinig <sam>
Component: AnimationsAssignee: Nobody <webkit-unassigned>
Status: RESOLVED CONFIGURATION CHANGED    
Severity: Normal CC: ahmad.saleem792, ap, bfulgham, dino, graouts, webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   
Bug Depends on: 189299    
Bug Blocks:    
Attachments:
Description Flags
Reduced Test Case none

Description Sam Weinig 2020-11-13 09:49:10 PST 
Created attachment 414056 [details]
Reduced Test Case

The value of animation at time 0 does not match Firefox (or WPT test expectations) for color accumulate composite test. Reduced test case attached.

`
  target.style[idlName] = 'rgb(128, 128, 128)';
  const animation = target.animate({ [idlName]: ['rgb(255, 0, 0)', 'rgb(0, 0, 255)'] }, { duration: 1000, composite: 'accumulate' });
  testAnimationSamples(animation, idlName, [{ time: 0,  expected: 'rgb(255, 128, 128)' }]);
`

This reduction was extracted from http://wpt.live/web-animations/animation-model/animation-types/accumulation-per-property-002.html
Comment 1 Radar WebKit Bug Importer 2020-11-20 09:50:15 PST 
<rdar://problem/71631573>
Comment 2 Antoine Quint 2020-11-21 00:38:47 PST 
Since we don't support composite operations (bug 189299), I expect instead of accumulating over the base value we are replacing it entirely.
Comment 3 Ahmad Saleem 2022-09-02 16:15:11 PDT 
Attached test case show following for all browsers (Chrome Canary 107, Firefox Nightly 106 and Safari Technology Preview 152):

PASS
The value should be rgb(255, 128, 128) at 0ms
The value is rgb(255, 128, 128) at 0ms

Is anything else needed here? WPT Live link test still has 20 failures in STP 152, 1 in Firefox Nightly 106 and 12 in Chrome Canary 107.
Comment 4 Antoine Quint 2022-09-12 07:12:27 PDT 
Yes, since composite operations are now supported, this particular issue seems addressed.