mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-10-23 18:26:15 +00:00
38a633181f
frame->Preserves3D() is whether the frame's parent has transform-style: preserve-3d, which means that the frame is part of the same 3-D scene as its parent. frame->Preserves3DChildren() is whether the frame itself has transform-style: preserve-3d, which means that the frame is part of the same 3-D scene as its children. Neither of these are valid cases for doing off-main-thread (OMT) animation because all of the layers in a preserve-3d scene are currently siblings of each other, rather than preserving ancestor/descendant relationships. This means that it's not valid to animate transform of the parent on the compositor because the compositor animation won't update any of its children that have layers. Likewise, it's not valid to animate transform of the child on the compositor because the code that sends transform information to the compositor doesn't handle the accumulation of transforms needed to get the "right" transform for the child (i.e., with the transforms of its ancestors up to the top of the 3-D scene merged in). This means that we do OMT animation for slightly fewer cases with the patch than we did without the patch. This means it's pretty low risk in terms of correctness, although there's a chance it might regress performance on one of the (somewhat limited) set of cases where the optimization was valid. (Bug 779598 covers doing OMT animation for preserve-3d cases, and depends on the work ongoing in bug 1097464.) The animate-preserve3d-parent.html reftest doesn't fail without the patch, since something seems to invalidate in the test; it was testing the testcase that showed correct behavior when the mouse was moving, so this isn't incredibly surprising (although that invalidation from mouse movement is itself worth debugging). The animate-preserve3d-child.html test does fail without the patch, though. (With an initial transform of none instead of the 30deg transform, both tests also show an invalidation bug without the patch.)
34 lines
581 B
HTML
34 lines
581 B
HTML
<!DOCTYPE HTML>
|
|
<html>
|
|
<title>Testcase, bug 1176969</title>
|
|
<style>
|
|
|
|
body { padding: 50px }
|
|
|
|
#grandparent { perspective: 400px }
|
|
|
|
#parent {
|
|
background: blue;
|
|
height: 200px; width: 200px;
|
|
border: 1px solid black;
|
|
transform-style: preserve-3d;
|
|
transform: rotateX(-45deg) rotateY(-45deg) rotateZ(-45deg);
|
|
will-change: transform;
|
|
}
|
|
|
|
#child {
|
|
transform: translateZ(15px);
|
|
height: 100px; width: 100px; margin: 50px;
|
|
background: yellow;
|
|
box-shadow: 3px 3px olive;
|
|
}
|
|
|
|
</style>
|
|
|
|
<div id="grandparent">
|
|
<div id="parent">
|
|
<div id="child">
|
|
</div>
|
|
</div>
|
|
</div>
|