1817499 - [wpt-sync] Sync PR 38572 - Fix layers having a globalAlpha, shadow and filter.

Status: RESOLVED FIXED

(Core :: DOM: Core & HTML, task, P4)

Description

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Sync web-platform-tests PR 38572 into mozilla-central (this bug is closed when the sync is complete).

PR: https://github.com/web-platform-tests/wpt/pull/38572
Details from upstream follow.

Jean-Philippe Gravel <[e-mail]> wrote:

Fix layers having a globalAlpha, shadow and filter.

When drawing shadows with a globalAlpha, both the foreground and the
shadow should be transparent. In other word, the shadow should be
visible through the foreground. This can't be done by setting the alpha
and shadow filter on the same layer since the alpha gets applied to the
result of the filter. The alpha must be applied first. To achieve this,
two nested layers must be used, with the inner one applying the
globalAlpha and the outer one applying the shadow.

This was correctly implemented for normal shadows, but it turns out that
shadows can also be implemnted with a "drop-shadow" filter. This means
the same logic applies, for filters: they can't be applied on the same
layer as a globalAlpha.

Change-Id: I6b59057e14661d489c0e5c81bd4dc0d6d3e406eb
Bug: 1396372
Reviewed-on: https://chromium-review.googlesource.com/4265374
WPT-Export-Revision: cd1c2c05b66314d2148b6f86613358174cb8c3d5

Comment 1

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

PR 38572 applied with additional changes from upstream: 44fdb6b93fecab82c052fa687368ec2ef28e444a, 63548ad3ecae3fad9e9dcc7c2c5962a5c33ccb39, e00b1606589c1f5ef7e3de052b6507dd19e90108, df22633a4118c2baaeaead8e05c202744d23ab92, 24ce9ca1f4959c0b14d1abb9b12ce35b58c68f99, 27ae5af35c48530aca3ba94823eafc570a2704bd, 40bafce0240d329546e14e72fcd08e7b14e91a61, bcf4a27c0a9dbb07d974a880acb26eb289a85c7e

Comment 2

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Pushed to try (stability) https://treeherder.mozilla.org/#/jobs?repo=try&revision=ab9ca192e7d11e2751ffef08144340ecc89c96be

Comment 3

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

CI Results

Ran 9 Firefox configurations based on mozilla-central, and Firefox, Chrome, and Safari on GitHub CI

Total 6 tests

Status Summary

Firefox

FAIL : 4
TIMEOUT: 2

Chrome

PASS : 3
FAIL : 3

Safari

FAIL : 4
TIMEOUT: 2

Links

Gecko CI (Treeherder)
GitHub PR Head
GitHub PR Base

Details

New Tests That Don't Pass

• /html/canvas/element/layers/2d.layer.global-states.alpha.filter.shadow.html [wpt.fyi]: FAIL (Chrome: FAIL, Safari: FAIL)
• /html/canvas/element/layers/2d.layer.global-states.no_global_states.html [wpt.fyi]: FAIL (Chrome: PASS, Safari: FAIL)
• /html/canvas/offscreen/layers/2d.layer.global-states.alpha.filter.shadow.html [wpt.fyi]: FAIL (Chrome: FAIL, Safari: FAIL)
• /html/canvas/offscreen/layers/2d.layer.global-states.alpha.filter.shadow.w.html [wpt.fyi]: TIMEOUT (Chrome: FAIL, Safari: TIMEOUT)
• /html/canvas/offscreen/layers/2d.layer.global-states.no_global_states.html [wpt.fyi]: FAIL (Chrome: PASS, Safari: FAIL)
• /html/canvas/offscreen/layers/2d.layer.global-states.no_global_states.w.html [wpt.fyi]: TIMEOUT (Chrome: PASS, Safari: TIMEOUT)

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/7ce63b648ce8
[wpt PR 38572] - Fix layers having a globalAlpha, shadow and filter., a=testonly
https://hg.mozilla.org/integration/autoland/rev/842b8ba1d54d
[wpt PR 38572] - Update wpt metadata, a=testonly

Comment 5

[Noemi Erli[:noemi_erli]]

https://hg.mozilla.org/mozilla-central/rev/7ce63b648ce8
https://hg.mozilla.org/mozilla-central/rev/842b8ba1d54d