cc: Clip delegated quads to the correct clip rect.

cc: Clip delegated quads to the correct clip rect.

The clip rect of the delegated renderer layer needs to be honored by the quads
that it generates.

1) Intersect any clip rects in the delegated quads with the
DelegatedRendererLayer's clip rect.

2) If a quad has no clip rect, then set it to the entire rect of the
DelegatedRendererLayer in its target space, so that they will not go outside
of the layer's bounds.

Tests:
DelegatedRendererLayerImplTestTransform.QuadsUnclipped_NoSurface
DelegatedRendererLayerImplTestTransform.QuadsClipped_NoSurface
DelegatedRendererLayerImplTestTransform.QuadsUnclipped_Surface
DelegatedRendererLayerImplTestTransform.QuadsClipped_Surface
DelegatedRendererLayerImplTestClip.QuadsUnclipped_LayerUnclipped_NoSurface
DelegatedRendererLayerImplTestClip.QuadsClipped_LayerUnclipped_NoSurface
DelegatedRendererLayerImplTestClip.QuadsUnclipped_LayerClipped_NoSurface
DelegatedRendererLayerImplTestClip.QuadsClipped_LayerClipped_NoSurface
DelegatedRendererLayerImplTestClip.QuadsUnclipped_LayerUnclipped_Surface
DelegatedRendererLayerImplTestClip.QuadsClipped_LayerUnclipped_Surface
DelegatedRendererLayerImplTestClip.QuadsUnclipped_LayerClipped_Surface
DelegatedRendererLayerImplTestClip.QuadsClipped_LayerClipped_Surface

R=piman
BUG=169089
Depends on: https://codereview.chromium.org/11871008

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=178143

[danakj, 2013-01-21 22:10:47]

I left clipped_rect_in_target alone because it's being removed entirely in
https://codereview.chromium.org/11871008

[jamesr, 2013-01-21 22:47:38]

BUG= line looks wrong.

How are the delegated quads intended to be clipped?  Is this done by the child
or parent compositor?

[danakj, 2013-01-21 22:48:58]

On 2013/01/21 22:47:38, jamesr wrote:
> BUG= line looks wrong.

Er, fixed.

> How are the delegated quads intended to be clipped?  Is this done by the child
> or parent compositor?

By the parent compositor. It can choose to clip them smaller than the child
compositor's viewport (think resizing a window).

[danakj, 2013-01-21 22:55:23]

Rebasing the unit tests on top of https://codereview.chromium.org/11871008 is a
little non-trivial. I'm going to split them up into smaller tests so it's more
clear what's being tested there.

[jamesr, 2013-01-21 23:00:07]

> > How are the delegated quads intended to be clipped?  Is this done by the
child
> > or parent compositor?
> 
> By the parent compositor. It can choose to clip them smaller than the child
> compositor's viewport (think resizing a window).

Sure, but how?  The parent can only set a GL scissor if the transform to the
surface the delegated content renders into keeps axis-aligned-rects
axis-aligned-rects, otherwise we need a render surface for arbitrary
quad+transform combinations.  Do we always render the delegated content to a
render surface?  If not, how do we generate one without running
LayerTreeHostCommon::calcDraw...() again?

[danakj, 2013-01-21 23:02:51]

On 2013/01/21 23:00:07, jamesr wrote:
> > > How are the delegated quads intended to be clipped?  Is this done by the
> child
> > > or parent compositor?
> > 
> > By the parent compositor. It can choose to clip them smaller than the child
> > compositor's viewport (think resizing a window).
> 
> Sure, but how?  The parent can only set a GL scissor if the transform to the
> surface the delegated content renders into keeps axis-aligned-rects
> axis-aligned-rects, otherwise we need a render surface for arbitrary
> quad+transform combinations.  Do we always render the delegated content to a
> render surface?  If not, how do we generate one without running
> LayerTreeHostCommon::calcDraw...() again?

If the delegated render layer is not axis aligned to its target, it gets a
render surface. This is verified by
DelegatedRendererLayerImplTestSimple.DoesOwnARenderSurfaceForTransform

Then it does not muck with the clip rects of its delegated quads at all, as they
will be clipped for free.

If it does not own a render surface, then it needs to clip everything to its
rect. It does this by setting/changing the clip_rect on all the quads in its
root pass. Then the gl_renderer will use a scissor to clip them to the bounds of
the delegated renderer layer's bounds.

[danakj, 2013-01-21 23:56:05]

Rebased it on https://codereview.chromium.org/11871008 and cleaned up/simplified
the unit tests a lot.

[piman, 2013-01-22 18:48:22]

lgtm

[commit-bot: I haz the power, 2013-01-22 18:52:20]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/danakj@chromium.org/12040011/11001

[commit-bot: I haz the power, 2013-01-22 22:55:15]

Change committed as 178143