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
151
152
153
154
155
156
157
|
/*
* Copyright 2010 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef GrClip_DEFINED
#define GrClip_DEFINED
#include "GrTypes.h"
#include "SkRRect.h"
#include "SkRect.h"
class GrAppliedClip;
class GrContext;
class GrRenderTargetContext;
/**
* GrClip is an abstract base class for applying a clip. It constructs a clip mask if necessary, and
* fills out a GrAppliedClip instructing the caller on how to set up the draw state.
*/
class GrClip {
public:
virtual bool quickContains(const SkRect&) const = 0;
virtual bool quickContains(const SkRRect& rrect) const {
return this->quickContains(rrect.getBounds());
}
virtual void getConservativeBounds(int width, int height, SkIRect* devResult,
bool* isIntersectionOfRects = nullptr) const = 0;
/**
* This computes a GrAppliedClip from the clip which in turn can be used to build a GrPipeline.
* To determine the appropriate clipping implementation the GrClip subclass must know whether
* the draw will enable HW AA or uses the stencil buffer. On input 'bounds' is a conservative
* bounds of the draw that is to be clipped. After return 'bounds' has been intersected with a
* conservative bounds of the clip. A return value of false indicates that the draw can be
* skipped as it is fully clipped out.
*/
virtual bool apply(GrContext*, GrRenderTargetContext*, bool useHWAA,
bool hasUserStencilSettings, GrAppliedClip* result,
SkRect* bounds) const = 0;
virtual ~GrClip() {}
/**
* This method quickly and conservatively determines whether the entire clip is equivalent to
* intersection with a rrect. This will only return true if the rrect does not fully contain
* the render target bounds. Moreover, the returned rrect need not be contained by the render
* target bounds. We assume all draws will be implicitly clipped by the render target bounds.
*
* @param rtBounds The bounds of the render target that the clip will be applied to.
* @param rrect If return is true rrect will contain the rrect equivalent to the clip within
* rtBounds.
* @param aa If return is true aa will indicate whether the rrect clip is antialiased.
* @return true if the clip is equivalent to a single rrect, false otherwise.
*
*/
virtual bool isRRect(const SkRect& rtBounds, SkRRect* rrect, GrAA* aa) const = 0;
/**
* This is the maximum distance that a draw may extend beyond a clip's boundary and still count
* count as "on the other side". We leave some slack because floating point rounding error is
* likely to blame. The rationale for 1e-3 is that in the coverage case (and barring unexpected
* rounding), as long as coverage stays within 0.5 * 1/256 of its intended value it shouldn't
* have any effect on the final pixel values.
*/
constexpr static SkScalar kBoundsTolerance = 1e-3f;
/**
* Returns true if the given query bounds count as entirely inside the clip.
*
* @param innerClipBounds device-space rect contained by the clip (SkRect or SkIRect).
* @param queryBounds device-space bounds of the query region.
*/
template <typename TRect>
constexpr static bool IsInsideClip(const TRect& innerClipBounds, const SkRect& queryBounds) {
return innerClipBounds.fRight - innerClipBounds.fLeft > kBoundsTolerance &&
innerClipBounds.fBottom - innerClipBounds.fTop > kBoundsTolerance &&
innerClipBounds.fLeft < queryBounds.fLeft + kBoundsTolerance &&
innerClipBounds.fTop < queryBounds.fTop + kBoundsTolerance &&
innerClipBounds.fRight > queryBounds.fRight - kBoundsTolerance &&
innerClipBounds.fBottom > queryBounds.fBottom - kBoundsTolerance;
}
/**
* Returns true if the given query bounds count as entirely outside the clip.
*
* @param outerClipBounds device-space rect that contains the clip (SkRect or SkIRect).
* @param queryBounds device-space bounds of the query region.
*/
template <typename TRect>
constexpr static bool IsOutsideClip(const TRect& outerClipBounds, const SkRect& queryBounds) {
return
// Is the clip so small that it is effectively empty?
outerClipBounds.fRight - outerClipBounds.fLeft <= kBoundsTolerance ||
outerClipBounds.fBottom - outerClipBounds.fTop <= kBoundsTolerance ||
// Are the query bounds effectively outside the clip?
outerClipBounds.fLeft >= queryBounds.fRight - kBoundsTolerance ||
outerClipBounds.fTop >= queryBounds.fBottom - kBoundsTolerance ||
outerClipBounds.fRight <= queryBounds.fLeft + kBoundsTolerance ||
outerClipBounds.fBottom <= queryBounds.fTop + kBoundsTolerance;
}
/**
* Returns the minimal integer rect that counts as containing a given set of bounds.
*/
static SkIRect GetPixelIBounds(const SkRect& bounds) {
return SkIRect::MakeLTRB(SkScalarFloorToInt(bounds.fLeft + kBoundsTolerance),
SkScalarFloorToInt(bounds.fTop + kBoundsTolerance),
SkScalarCeilToInt(bounds.fRight - kBoundsTolerance),
SkScalarCeilToInt(bounds.fBottom - kBoundsTolerance));
}
/**
* Returns the minimal pixel-aligned rect that counts as containing a given set of bounds.
*/
static SkRect GetPixelBounds(const SkRect& bounds) {
return SkRect::MakeLTRB(SkScalarFloorToScalar(bounds.fLeft + kBoundsTolerance),
SkScalarFloorToScalar(bounds.fTop + kBoundsTolerance),
SkScalarCeilToScalar(bounds.fRight - kBoundsTolerance),
SkScalarCeilToScalar(bounds.fBottom - kBoundsTolerance));
}
/**
* Returns true if the given rect counts as aligned with pixel boundaries.
*/
static bool IsPixelAligned(const SkRect& rect) {
return SkScalarAbs(SkScalarRoundToScalar(rect.fLeft) - rect.fLeft) <= kBoundsTolerance &&
SkScalarAbs(SkScalarRoundToScalar(rect.fTop) - rect.fTop) <= kBoundsTolerance &&
SkScalarAbs(SkScalarRoundToScalar(rect.fRight) - rect.fRight) <= kBoundsTolerance &&
SkScalarAbs(SkScalarRoundToScalar(rect.fBottom) - rect.fBottom) <= kBoundsTolerance;
}
};
/**
* Specialized implementation for no clip.
*/
class GrNoClip final : public GrClip {
private:
bool quickContains(const SkRect&) const final { return true; }
bool quickContains(const SkRRect&) const final { return true; }
void getConservativeBounds(int width, int height, SkIRect* devResult,
bool* isIntersectionOfRects) const final {
devResult->setXYWH(0, 0, width, height);
if (isIntersectionOfRects) {
*isIntersectionOfRects = true;
}
}
bool apply(GrContext*, GrRenderTargetContext*, bool, bool, GrAppliedClip*,
SkRect*) const final {
return true;
}
bool isRRect(const SkRect&, SkRRect*, GrAA*) const override { return false; }
};
#endif
|