1 // Copyright 2014 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #ifndef CC_BASE_SIMPLE_ENCLOSED_REGION_H_
6 #define CC_BASE_SIMPLE_ENCLOSED_REGION_H_
7
8 #include <stddef.h>
9
10 #include <string>
11
12 #include "cc/base/base_export.h"
13 #include "ui/gfx/geometry/rect.h"
14
15 namespace cc {
16
17 class Region;
18
19 // A constant-sized approximation of a Region. The SimpleEnclosedRegion may
20 // exclude points in its approximation (may have false negatives) but will never
21 // include a point that would not be in the actual Region (no false positives).
22 class CC_BASE_EXPORT SimpleEnclosedRegion {
23 public:
SimpleEnclosedRegion()24 SimpleEnclosedRegion() : rect_() {}
SimpleEnclosedRegion(const SimpleEnclosedRegion & region)25 SimpleEnclosedRegion(const SimpleEnclosedRegion& region)
26 : rect_(region.rect_) {}
SimpleEnclosedRegion(const gfx::Rect & rect)27 explicit SimpleEnclosedRegion(const gfx::Rect& rect) : rect_(rect) {}
SimpleEnclosedRegion(int x,int y,int w,int h)28 SimpleEnclosedRegion(int x, int y, int w, int h) : rect_(x, y, w, h) {}
SimpleEnclosedRegion(int w,int h)29 SimpleEnclosedRegion(int w, int h) : rect_(w, h) {}
30 explicit SimpleEnclosedRegion(const Region& region);
31 ~SimpleEnclosedRegion();
32
33 const SimpleEnclosedRegion& operator=(const gfx::Rect& rect) {
34 rect_ = rect;
35 return *this;
36 }
37 const SimpleEnclosedRegion& operator=(const SimpleEnclosedRegion& region) {
38 rect_ = region.rect_;
39 return *this;
40 }
41
IsEmpty()42 bool IsEmpty() const { return rect_.IsEmpty(); }
Clear()43 void Clear() { rect_ = gfx::Rect(); }
GetRegionComplexity()44 size_t GetRegionComplexity() const { return rect_.IsEmpty() ? 0 : 1; }
45
Contains(const gfx::Point & point)46 bool Contains(const gfx::Point& point) const { return rect_.Contains(point); }
Contains(const gfx::Rect & rect)47 bool Contains(const gfx::Rect& rect) const { return rect_.Contains(rect); }
Contains(const SimpleEnclosedRegion & region)48 bool Contains(const SimpleEnclosedRegion& region) const {
49 return rect_.Contains(region.rect_);
50 }
51
Intersects(const gfx::Rect & rect)52 bool Intersects(const gfx::Rect& rect) const {
53 return rect_.Intersects(rect);
54 }
Intersects(const SimpleEnclosedRegion & region)55 bool Intersects(const SimpleEnclosedRegion& region) const {
56 return rect_.Intersects(region.rect_);
57 }
58
59 void Subtract(const gfx::Rect& sub_rect);
Subtract(const SimpleEnclosedRegion & sub_region)60 void Subtract(const SimpleEnclosedRegion& sub_region) {
61 Subtract(sub_region.rect_);
62 }
63 void Union(const gfx::Rect& new_rect);
Union(const SimpleEnclosedRegion & new_region)64 void Union(const SimpleEnclosedRegion& new_region) {
65 Union(new_region.rect_);
66 }
Intersect(const gfx::Rect & in_rect)67 void Intersect(const gfx::Rect& in_rect) { return rect_.Intersect(in_rect); }
Intersect(const SimpleEnclosedRegion & in_region)68 void Intersect(const SimpleEnclosedRegion& in_region) {
69 Intersect(in_region.rect_);
70 }
71
Equals(const SimpleEnclosedRegion & other)72 bool Equals(const SimpleEnclosedRegion& other) const {
73 bool both_empty = rect_.IsEmpty() && other.rect_.IsEmpty();
74 return both_empty || rect_ == other.rect_;
75 }
76
bounds()77 gfx::Rect bounds() const { return rect_; }
78
79 // The value of |i| must be less than GetRegionComplexity().
80 gfx::Rect GetRect(size_t i) const;
81
ToString()82 std::string ToString() const { return rect_.ToString(); }
83
84 private:
85 gfx::Rect rect_;
86 };
87
88 inline bool operator==(const SimpleEnclosedRegion& a,
89 const SimpleEnclosedRegion& b) {
90 return a.Equals(b);
91 }
92
93 inline bool operator!=(const SimpleEnclosedRegion& a,
94 const SimpleEnclosedRegion& b) {
95 return !(a == b);
96 }
97
SubtractSimpleEnclosedRegions(const SimpleEnclosedRegion & a,const SimpleEnclosedRegion & b)98 inline SimpleEnclosedRegion SubtractSimpleEnclosedRegions(
99 const SimpleEnclosedRegion& a,
100 const SimpleEnclosedRegion& b) {
101 SimpleEnclosedRegion result = a;
102 result.Subtract(b);
103 return result;
104 }
105
IntersectSimpleEnclosedRegions(const SimpleEnclosedRegion & a,const SimpleEnclosedRegion & b)106 inline SimpleEnclosedRegion IntersectSimpleEnclosedRegions(
107 const SimpleEnclosedRegion& a,
108 const SimpleEnclosedRegion& b) {
109 SimpleEnclosedRegion result = a;
110 result.Intersect(b);
111 return result;
112 }
113
UnionSimpleEnclosedRegions(const SimpleEnclosedRegion & a,const SimpleEnclosedRegion & b)114 inline SimpleEnclosedRegion UnionSimpleEnclosedRegions(
115 const SimpleEnclosedRegion& a,
116 const SimpleEnclosedRegion& b) {
117 SimpleEnclosedRegion result = a;
118 result.Union(b);
119 return result;
120 }
121
122 } // namespace cc
123
124 #endif // CC_BASE_SIMPLE_ENCLOSED_REGION_H_
125