1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
|
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "mozilla/layers/StackingContextHelper.h"
#include "mozilla/PresShell.h"
#include "UnitTransforms.h"
#include "nsDisplayList.h"
namespace mozilla {
namespace layers {
StackingContextHelper::StackingContextHelper()
: mBuilder(nullptr),
mScale(1.0f, 1.0f),
mAffectsClipPositioning(false),
mRasterizeLocally(false) {
// mOrigin remains at 0,0
}
StackingContextHelper::StackingContextHelper(
const StackingContextHelper& aParentSC, const ActiveScrolledRoot* aAsr,
nsIFrame* aContainerFrame, nsDisplayItem* aContainerItem,
wr::DisplayListBuilder& aBuilder, const wr::StackingContextParams& aParams,
const LayoutDeviceRect& aBounds)
: mBuilder(&aBuilder),
mScale(1.0f, 1.0f),
mDeferredTransformItem(aParams.mDeferredTransformItem),
mRasterizeLocally(aParams.mRasterizeLocally ||
aParentSC.mRasterizeLocally) {
mOrigin = aParentSC.mOrigin + aBounds.TopLeft();
// Compute scale for fallback rendering. We don't try to guess a scale for 3d
// transformed items
if (aParams.mBoundTransform) {
gfx::Matrix transform2d;
bool canDraw2D = aParams.mBoundTransform->CanDraw2D(&transform2d);
if (canDraw2D &&
aParams.reference_frame_kind != wr::WrReferenceFrameKind::Perspective &&
!aContainerFrame->Combines3DTransformWithAncestors()) {
mInheritedTransform = transform2d * aParentSC.mInheritedTransform;
int32_t apd = aContainerFrame->PresContext()->AppUnitsPerDevPixel();
nsRect r = LayoutDevicePixel::ToAppUnits(aBounds, apd);
mScale = FrameLayerBuilder::ChooseScale(
aContainerFrame, aContainerItem, r, aParentSC.mScale.width,
aParentSC.mScale.height, mInheritedTransform,
/* aCanDraw2D = */ true);
} else {
mScale = gfx::Size(1.0f, 1.0f);
mInheritedTransform = gfx::Matrix::Scaling(1.f, 1.f);
}
if (aParams.mAnimated) {
mSnappingSurfaceTransform =
gfx::Matrix::Scaling(mScale.width, mScale.height);
} else {
mSnappingSurfaceTransform =
transform2d * aParentSC.mSnappingSurfaceTransform;
}
} else if (aParams.reference_frame_kind == wr::WrReferenceFrameKind::Zoom &&
aContainerItem &&
aContainerItem->GetType() == DisplayItemType::TYPE_ASYNC_ZOOM &&
aContainerItem->Frame()) {
double resolution = aContainerItem->Frame()->PresShell()->GetResolution();
gfx::Matrix transform = gfx::Matrix::Scaling(resolution, resolution);
mInheritedTransform = transform * aParentSC.mInheritedTransform;
mScale = resolution * aParentSC.mScale;
MOZ_ASSERT(!aParams.mAnimated);
mSnappingSurfaceTransform = transform * aParentSC.mSnappingSurfaceTransform;
} else {
mInheritedTransform = aParentSC.mInheritedTransform;
mScale = aParentSC.mScale;
}
auto rasterSpace =
mRasterizeLocally
? wr::RasterSpace::Local(std::max(mScale.width, mScale.height))
: wr::RasterSpace::Screen();
MOZ_ASSERT(!aParams.clip.IsNone());
mReferenceFrameId = mBuilder->PushStackingContext(
aParams, wr::ToLayoutRect(aBounds), rasterSpace);
if (mReferenceFrameId) {
mSpaceAndClipChainHelper.emplace(aBuilder, mReferenceFrameId.ref());
}
mAffectsClipPositioning =
mReferenceFrameId.isSome() || (aBounds.TopLeft() != LayoutDevicePoint());
// If the parent stacking context has a deferred transform item, inherit it
// into this stacking context, as long as the ASR hasn't changed. Refer to
// the comments on StackingContextHelper::mDeferredTransformItem for an
// explanation of what goes in these fields.
if (aParentSC.mDeferredTransformItem &&
aAsr == (*aParentSC.mDeferredTransformItem)->GetActiveScrolledRoot()) {
if (mDeferredTransformItem) {
// If we are deferring another transform, put the combined transform from
// all the ancestor deferred items into mDeferredAncestorTransform
mDeferredAncestorTransform = aParentSC.GetDeferredTransformMatrix();
} else {
// We are not deferring another transform, so we can just inherit the
// parent stacking context's deferred data without any modification.
mDeferredTransformItem = aParentSC.mDeferredTransformItem;
mDeferredAncestorTransform = aParentSC.mDeferredAncestorTransform;
}
}
}
StackingContextHelper::~StackingContextHelper() {
if (mBuilder) {
mSpaceAndClipChainHelper.reset();
mBuilder->PopStackingContext(mReferenceFrameId.isSome());
}
}
const Maybe<nsDisplayTransform*>&
StackingContextHelper::GetDeferredTransformItem() const {
return mDeferredTransformItem;
}
Maybe<gfx::Matrix4x4> StackingContextHelper::GetDeferredTransformMatrix()
const {
if (mDeferredTransformItem) {
// See the comments on StackingContextHelper::mDeferredTransformItem for
// an explanation of what's stored in mDeferredTransformItem and
// mDeferredAncestorTransform. Here we need to return the combined transform
// transform from all the deferred ancestors, including
// mDeferredTransformItem.
gfx::Matrix4x4 result =
(*mDeferredTransformItem)->GetTransform().GetMatrix();
if (mDeferredAncestorTransform) {
result = result * *mDeferredAncestorTransform;
}
return Some(result);
} else {
return Nothing();
}
}
} // namespace layers
} // namespace mozilla
|
