704469 - overflow: hidden, auto, or scroll removes css3-3d-transforms 'perspective'

Status: RESOLVED FIXED

(Core :: Layout, defect, P2)

Description

[Dirk]

Attachment: index.html

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_6_8) AppleWebKit/534.51.22 (KHTML, like Gecko) Version/5.1.1 Safari/534.51.22

Steps to reproduce:

Apply CSS3 3D "-moz-perspective" and "overflow: hidden" to block level element




Actual results:

Child elements are rendered as if parent would not have a "perspective" attribute.


Expected results:

Perspective distortion should be applied to child elements. See Demo at http://www.eleqtriq.com/wp-content/static/demos/2011/mozbugs/

Comment 1

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

This seems likely to be related to the fact that overflow:hidden creates two frames, one nested inside the other (the inner one having an anonymous box style).

I think the problem here is that nsDisplayTransform::GetResultingTransformMatrix (in layout/base/nsDisplayList.cpp) should replace:

2539   const nsStyleDisplay* parentDisp = nsnull;
2540   if (aFrame->GetParent()) {
2541     parentDisp = aFrame->GetParent()->GetStyleDisplay();
2542   }

with:

const nsStyleDisplay *parentDisp = nsnull;
nsStyleContext *parentStyleContext = aFrame->GetStyleContext()->GetParent();
if (parentStyleContext) {
  parentDisp = parentStyleContext->GetStyleDisplay();
}

so that it gets the perspective from the style parent.

Comment 2

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

I think it would be good to get this fixed for Firefox 10 (where, if my memory is correct, 3-D transforms are a new feature).

Comment 3

[Matt Woodrow (:mattwoodrow)]

Attachment: Check style parent, instead of frame parent

Thanks for looking into this dbaron

Requesting aurora/beta approval since this fixes a bug with our implementation of 3d transforms. Should be very low risk, and well covered by tests.

Comment 4

[Alex Keybl [:akeybl]]

Comment on attachment 585545 [details] [diff] [review]
Check style parent, instead of frame parent

[Triage Comment]
Please re-nominate once this has landed on m-c and gotten some bake time.

Comment 5

[Matt Woodrow (:mattwoodrow)]

https://hg.mozilla.org/integration/mozilla-inbound/rev/7d6b4a1557f4

Comment 6

[Marco Bonardo [:mak]]

https://hg.mozilla.org/mozilla-central/rev/7d6b4a1557f4

Comment 7

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Comment on attachment 585545 [details] [diff] [review]
Check style parent, instead of frame parent

renominating per comment 4

Comment 8

[Matt Woodrow (:mattwoodrow)]

https://hg.mozilla.org/releases/mozilla-beta/rev/0dfaeb9d662a
https://hg.mozilla.org/releases/mozilla-aurora/rev/89407d03f983