ui/gfx/geometry/rect.h

   1 // Copyright (c) 2012 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 // Defines a simple integer rectangle class.  The containment semantics
   6 // are array-like; that is, the coordinate (x, y) is considered to be
   7 // contained by the rectangle, but the coordinate (x + width, y) is not.
   8 // The class will happily let you create malformed rectangles (that is,
   9 // rectangles with negative width and/or height), but there will be assertions
  10 // in the operations (such as Contains()) to complain in this case.
  11
  12 #ifndef UI_GFX_GEOMETRY_RECT_H_
  13 #define UI_GFX_GEOMETRY_RECT_H_
  14
  15 #include <cmath>
  16 #include <iosfwd>
  17 #include <string>
  18
  19 #include "base/numerics/safe_conversions.h"
  20 #include "ui/gfx/geometry/point.h"
  21 #include "ui/gfx/geometry/size.h"
  22 #include "ui/gfx/geometry/vector2d.h"
  23
  24 #if defined(OS_WIN)
  25 typedef struct tagRECT RECT;
  26 #elif defined(OS_MACOSX)
  27 typedef struct CGRect CGRect;
  28 #endif
  29
  30 namespace gfx {
  31
  32 class Insets;
  33
  34 class GFX_EXPORT Rect {
  35  public:
  36   Rect() {}
  37   Rect(int width, int height) : size_(width, height) {}
  38   Rect(int x, int y, int width, int height)
  39       : origin_(x, y), size_(width, height) {}
  40   explicit Rect(const Size& size) : size_(size) {}
  41   Rect(const Point& origin, const Size& size) : origin_(origin), size_(size) {}
  42
  43 #if defined(OS_WIN)
  44   explicit Rect(const RECT& r);
  45 #elif defined(OS_MACOSX)
  46   explicit Rect(const CGRect& r);
  47 #endif
  48
  49   ~Rect() {}
  50
  51 #if defined(OS_WIN)
  52   // Construct an equivalent Win32 RECT object.
  53   RECT ToRECT() const;
  54 #elif defined(OS_MACOSX)
  55   // Construct an equivalent CoreGraphics object.
  56   CGRect ToCGRect() const;
  57 #endif
  58
  59   int x() const { return origin_.x(); }
  60   void set_x(int x) { origin_.set_x(x); }
  61
  62   int y() const { return origin_.y(); }
  63   void set_y(int y) { origin_.set_y(y); }
  64
  65   int width() const { return size_.width(); }
  66   void set_width(int width) { size_.set_width(width); }
  67
  68   int height() const { return size_.height(); }
  69   void set_height(int height) { size_.set_height(height); }
  70
  71   const Point& origin() const { return origin_; }
  72   void set_origin(const Point& origin) { origin_ = origin; }
  73
  74   const Size& size() const { return size_; }
  75   void set_size(const Size& size) { size_ = size; }
  76
  77   int right() const { return x() + width(); }
  78   int bottom() const { return y() + height(); }
  79
  80   Point top_right() const { return Point(right(), y()); }
  81   Point bottom_left() const { return Point(x(), bottom()); }
  82   Point bottom_right() const { return Point(right(), bottom()); }
  83
  84   Vector2d OffsetFromOrigin() const { return Vector2d(x(), y()); }
  85
  86   void SetRect(int x, int y, int width, int height) {
  87     origin_.SetPoint(x, y);
  88     size_.SetSize(width, height);
  89   }
  90
  91   // Shrink the rectangle by a horizontal and vertical distance on all sides.
  92   void Inset(int horizontal, int vertical) {
  93     Inset(horizontal, vertical, horizontal, vertical);
  94   }
  95
  96   // Shrink the rectangle by the given insets.
  97   void Inset(const Insets& insets);
  98
  99   // Shrink the rectangle by the specified amount on each side.
 100   void Inset(int left, int top, int right, int bottom);
 101
 102   // Move the rectangle by a horizontal and vertical distance.
 103   void Offset(int horizontal, int vertical);
 104   void Offset(const Vector2d& distance) { Offset(distance.x(), distance.y()); }
 105   void operator+=(const Vector2d& offset);
 106   void operator-=(const Vector2d& offset);
 107
 108   Insets InsetsFrom(const Rect& inner) const;
 109
 110   // Returns true if the area of the rectangle is zero.
 111   bool IsEmpty() const { return size_.IsEmpty(); }
 112
 113   // A rect is less than another rect if its origin is less than
 114   // the other rect's origin. If the origins are equal, then the
 115   // shortest rect is less than the other. If the origin and the
 116   // height are equal, then the narrowest rect is less than.
 117   // This comparison is required to use Rects in sets, or sorted
 118   // vectors.
 119   bool operator<(const Rect& other) const;
 120
 121   // Returns true if the point identified by point_x and point_y falls inside
 122   // this rectangle.  The point (x, y) is inside the rectangle, but the
 123   // point (x + width, y + height) is not.
 124   bool Contains(int point_x, int point_y) const;
 125
 126   // Returns true if the specified point is contained by this rectangle.
 127   bool Contains(const Point& point) const {
 128     return Contains(point.x(), point.y());
 129   }
 130
 131   // Returns true if this rectangle contains the specified rectangle.
 132   bool Contains(const Rect& rect) const;
 133
 134   // Returns true if this rectangle intersects the specified rectangle.
 135   // An empty rectangle doesn't intersect any rectangle.
 136   bool Intersects(const Rect& rect) const;
 137
 138   // Computes the intersection of this rectangle with the given rectangle.
 139   void Intersect(const Rect& rect);
 140
 141   // Computes the union of this rectangle with the given rectangle.  The union
 142   // is the smallest rectangle containing both rectangles.
 143   void Union(const Rect& rect);
 144
 145   // Computes the rectangle resulting from subtracting |rect| from |*this|,
 146   // i.e. the bounding rect of |Region(*this) - Region(rect)|.
 147   void Subtract(const Rect& rect);
 148
 149   // Fits as much of the receiving rectangle into the supplied rectangle as
 150   // possible, becoming the result. For example, if the receiver had
 151   // a x-location of 2 and a width of 4, and the supplied rectangle had
 152   // an x-location of 0 with a width of 5, the returned rectangle would have
 153   // an x-location of 1 with a width of 4.
 154   void AdjustToFit(const Rect& rect);
 155
 156   // Returns the center of this rectangle.
 157   Point CenterPoint() const;
 158
 159   // Becomes a rectangle that has the same center point but with a size capped
 160   // at given |size|.
 161   void ClampToCenteredSize(const Size& size);
 162
 163   // Splits |this| in two halves, |left_half| and |right_half|.
 164   void SplitVertically(Rect* left_half, Rect* right_half) const;
 165
 166   // Returns true if this rectangle shares an entire edge (i.e., same width or
 167   // same height) with the given rectangle, and the rectangles do not overlap.
 168   bool SharesEdgeWith(const Rect& rect) const;
 169
 170   // Returns the manhattan distance from the rect to the point. If the point is
 171   // inside the rect, returns 0.
 172   int ManhattanDistanceToPoint(const Point& point) const;
 173
 174   // Returns the manhattan distance between the contents of this rect and the
 175   // contents of the given rect. That is, if the intersection of the two rects
 176   // is non-empty then the function returns 0. If the rects share a side, it
 177   // returns the smallest non-zero value appropriate for int.
 178   int ManhattanInternalDistance(const Rect& rect) const;
 179
 180   std::string ToString() const;
 181
 182  private:
 183   gfx::Point origin_;
 184   gfx::Size size_;
 185 };
 186
 187 inline bool operator==(const Rect& lhs, const Rect& rhs) {
 188   return lhs.origin() == rhs.origin() && lhs.size() == rhs.size();
 189 }
 190
 191 inline bool operator!=(const Rect& lhs, const Rect& rhs) {
 192   return !(lhs == rhs);
 193 }
 194
 195 GFX_EXPORT Rect operator+(const Rect& lhs, const Vector2d& rhs);
 196 GFX_EXPORT Rect operator-(const Rect& lhs, const Vector2d& rhs);
 197
 198 inline Rect operator+(const Vector2d& lhs, const Rect& rhs) {
 199   return rhs + lhs;
 200 }
 201
 202 GFX_EXPORT Rect IntersectRects(const Rect& a, const Rect& b);
 203 GFX_EXPORT Rect UnionRects(const Rect& a, const Rect& b);
 204 GFX_EXPORT Rect SubtractRects(const Rect& a, const Rect& b);
 205
 206 // Constructs a rectangle with |p1| and |p2| as opposite corners.
 207 //
 208 // This could also be thought of as "the smallest rect that contains both
 209 // points", except that we consider points on the right/bottom edges of the
 210 // rect to be outside the rect.  So technically one or both points will not be
 211 // contained within the rect, because they will appear on one of these edges.
 212 GFX_EXPORT Rect BoundingRect(const Point& p1, const Point& p2);
 213
 214 inline Rect ScaleToEnclosingRect(const Rect& rect,
 215                                  float x_scale,
 216                                  float y_scale) {
 217   if (x_scale == 1.f && y_scale == 1.f)
 218     return rect;
 219   // These next functions cast instead of using e.g. ToFlooredInt() because we
 220   // haven't checked to ensure that the clamping behavior of the helper
 221   // functions doesn't degrade performance, and callers shouldn't be passing
 222   // values that cause overflow anyway.
 223   DCHECK(base::IsValueInRangeForNumericType<int>(
 224       std::floor(rect.x() * x_scale)));
 225   DCHECK(base::IsValueInRangeForNumericType<int>(
 226       std::floor(rect.y() * y_scale)));
 227   DCHECK(base::IsValueInRangeForNumericType<int>(
 228       std::ceil(rect.right() * x_scale)));
 229   DCHECK(base::IsValueInRangeForNumericType<int>(
 230       std::ceil(rect.bottom() * y_scale)));
 231   int x = static_cast<int>(std::floor(rect.x() * x_scale));
 232   int y = static_cast<int>(std::floor(rect.y() * y_scale));
 233   int r = rect.width() == 0 ?
 234       x : static_cast<int>(std::ceil(rect.right() * x_scale));
 235   int b = rect.height() == 0 ?
 236       y : static_cast<int>(std::ceil(rect.bottom() * y_scale));
 237   return Rect(x, y, r - x, b - y);
 238 }
 239
 240 inline Rect ScaleToEnclosingRect(const Rect& rect, float scale) {
 241   return ScaleToEnclosingRect(rect, scale, scale);
 242 }
 243
 244 inline Rect ScaleToEnclosedRect(const Rect& rect,
 245                                 float x_scale,
 246                                 float y_scale) {
 247   if (x_scale == 1.f && y_scale == 1.f)
 248     return rect;
 249   DCHECK(base::IsValueInRangeForNumericType<int>(
 250       std::ceil(rect.x() * x_scale)));
 251   DCHECK(base::IsValueInRangeForNumericType<int>(
 252       std::ceil(rect.y() * y_scale)));
 253   DCHECK(base::IsValueInRangeForNumericType<int>(
 254       std::floor(rect.right() * x_scale)));
 255   DCHECK(base::IsValueInRangeForNumericType<int>(
 256       std::floor(rect.bottom() * y_scale)));
 257   int x = static_cast<int>(std::ceil(rect.x() * x_scale));
 258   int y = static_cast<int>(std::ceil(rect.y() * y_scale));
 259   int r = rect.width() == 0 ?
 260       x : static_cast<int>(std::floor(rect.right() * x_scale));
 261   int b = rect.height() == 0 ?
 262       y : static_cast<int>(std::floor(rect.bottom() * y_scale));
 263   return Rect(x, y, r - x, b - y);
 264 }
 265
 266 inline Rect ScaleToEnclosedRect(const Rect& rect, float scale) {
 267   return ScaleToEnclosedRect(rect, scale, scale);
 268 }
 269
 270 // This is declared here for use in gtest-based unit tests but is defined in
 271 // the gfx_test_support target. Depend on that to use this in your unit test.
 272 // This should not be used in production code - call ToString() instead.
 273 void PrintTo(const Rect& rect, ::std::ostream* os);
 274
 275 }  // namespace gfx
 276
 277 #endif  // UI_GFX_GEOMETRY_RECT_H_