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/rect_f.h"
  22 #include "ui/gfx/geometry/size.h"
  23 #include "ui/gfx/geometry/vector2d.h"
  24
  25 #if defined(OS_WIN)
  26 typedef struct tagRECT RECT;
  27 #elif defined(OS_MACOSX)
  28 typedef struct CGRect CGRect;
  29 #endif
  30
  31 namespace gfx {
  32
  33 class Insets;
  34
  35 class GFX_EXPORT Rect {
  36  public:
  37   Rect() {}
  38   Rect(int width, int height) : size_(width, height) {}
  39   Rect(int x, int y, int width, int height)
  40       : origin_(x, y), size_(width, height) {}
  41   explicit Rect(const Size& size) : size_(size) {}
  42   Rect(const Point& origin, const Size& size) : origin_(origin), size_(size) {}
  43
  44 #if defined(OS_WIN)
  45   explicit Rect(const RECT& r);
  46 #elif defined(OS_MACOSX)
  47   explicit Rect(const CGRect& r);
  48 #endif
  49
  50   ~Rect() {}
  51
  52 #if defined(OS_WIN)
  53   // Construct an equivalent Win32 RECT object.
  54   RECT ToRECT() const;
  55 #elif defined(OS_MACOSX)
  56   // Construct an equivalent CoreGraphics object.
  57   CGRect ToCGRect() const;
  58 #endif
  59
  60   operator RectF() const {
  61     return RectF(static_cast<float>(x()), static_cast<float>(y()),
  62                  static_cast<float>(width()), static_cast<float>(height()));
  63   }
  64
  65   int x() const { return origin_.x(); }
  66   void set_x(int x) { origin_.set_x(x); }
  67
  68   int y() const { return origin_.y(); }
  69   void set_y(int y) { origin_.set_y(y); }
  70
  71   int width() const { return size_.width(); }
  72   void set_width(int width) { size_.set_width(width); }
  73
  74   int height() const { return size_.height(); }
  75   void set_height(int height) { size_.set_height(height); }
  76
  77   const Point& origin() const { return origin_; }
  78   void set_origin(const Point& origin) { origin_ = origin; }
  79
  80   const Size& size() const { return size_; }
  81   void set_size(const Size& size) { size_ = size; }
  82
  83   int right() const { return x() + width(); }
  84   int bottom() const { return y() + height(); }
  85
  86   Point top_right() const { return Point(right(), y()); }
  87   Point bottom_left() const { return Point(x(), bottom()); }
  88   Point bottom_right() const { return Point(right(), bottom()); }
  89
  90   Vector2d OffsetFromOrigin() const { return Vector2d(x(), y()); }
  91
  92   void SetRect(int x, int y, int width, int height) {
  93     origin_.SetPoint(x, y);
  94     size_.SetSize(width, height);
  95   }
  96
  97   // Shrink the rectangle by a horizontal and vertical distance on all sides.
  98   void Inset(int horizontal, int vertical) {
  99     Inset(horizontal, vertical, horizontal, vertical);
 100   }
 101
 102   // Shrink the rectangle by the given insets.
 103   void Inset(const Insets& insets);
 104
 105   // Shrink the rectangle by the specified amount on each side.
 106   void Inset(int left, int top, int right, int bottom);
 107
 108   // Move the rectangle by a horizontal and vertical distance.
 109   void Offset(int horizontal, int vertical);
 110   void Offset(const Vector2d& distance) { Offset(distance.x(), distance.y()); }
 111   void operator+=(const Vector2d& offset);
 112   void operator-=(const Vector2d& offset);
 113
 114   Insets InsetsFrom(const Rect& inner) const;
 115
 116   // Returns true if the area of the rectangle is zero.
 117   bool IsEmpty() const { return size_.IsEmpty(); }
 118
 119   // A rect is less than another rect if its origin is less than
 120   // the other rect's origin. If the origins are equal, then the
 121   // shortest rect is less than the other. If the origin and the
 122   // height are equal, then the narrowest rect is less than.
 123   // This comparison is required to use Rects in sets, or sorted
 124   // vectors.
 125   bool operator<(const Rect& other) const;
 126
 127   // Returns true if the point identified by point_x and point_y falls inside
 128   // this rectangle.  The point (x, y) is inside the rectangle, but the
 129   // point (x + width, y + height) is not.
 130   bool Contains(int point_x, int point_y) const;
 131
 132   // Returns true if the specified point is contained by this rectangle.
 133   bool Contains(const Point& point) const {
 134     return Contains(point.x(), point.y());
 135   }
 136
 137   // Returns true if this rectangle contains the specified rectangle.
 138   bool Contains(const Rect& rect) const;
 139
 140   // Returns true if this rectangle intersects the specified rectangle.
 141   // An empty rectangle doesn't intersect any rectangle.
 142   bool Intersects(const Rect& rect) const;
 143
 144   // Computes the intersection of this rectangle with the given rectangle.
 145   void Intersect(const Rect& rect);
 146
 147   // Computes the union of this rectangle with the given rectangle.  The union
 148   // is the smallest rectangle containing both rectangles.
 149   void Union(const Rect& rect);
 150
 151   // Computes the rectangle resulting from subtracting |rect| from |*this|,
 152   // i.e. the bounding rect of |Region(*this) - Region(rect)|.
 153   void Subtract(const Rect& rect);
 154
 155   // Fits as much of the receiving rectangle into the supplied rectangle as
 156   // possible, becoming the result. For example, if the receiver had
 157   // a x-location of 2 and a width of 4, and the supplied rectangle had
 158   // an x-location of 0 with a width of 5, the returned rectangle would have
 159   // an x-location of 1 with a width of 4.
 160   void AdjustToFit(const Rect& rect);
 161
 162   // Returns the center of this rectangle.
 163   Point CenterPoint() const;
 164
 165   // Becomes a rectangle that has the same center point but with a size capped
 166   // at given |size|.
 167   void ClampToCenteredSize(const Size& size);
 168
 169   // Splits |this| in two halves, |left_half| and |right_half|.
 170   void SplitVertically(Rect* left_half, Rect* right_half) const;
 171
 172   // Returns true if this rectangle shares an entire edge (i.e., same width or
 173   // same height) with the given rectangle, and the rectangles do not overlap.
 174   bool SharesEdgeWith(const Rect& rect) const;
 175
 176   // Returns the manhattan distance from the rect to the point. If the point is
 177   // inside the rect, returns 0.
 178   int ManhattanDistanceToPoint(const Point& point) const;
 179
 180   // Returns the manhattan distance between the contents of this rect and the
 181   // contents of the given rect. That is, if the intersection of the two rects
 182   // is non-empty then the function returns 0. If the rects share a side, it
 183   // returns the smallest non-zero value appropriate for int.
 184   int ManhattanInternalDistance(const Rect& rect) const;
 185
 186   std::string ToString() const;
 187
 188  private:
 189   gfx::Point origin_;
 190   gfx::Size size_;
 191 };
 192
 193 inline bool operator==(const Rect& lhs, const Rect& rhs) {
 194   return lhs.origin() == rhs.origin() && lhs.size() == rhs.size();
 195 }
 196
 197 inline bool operator!=(const Rect& lhs, const Rect& rhs) {
 198   return !(lhs == rhs);
 199 }
 200
 201 GFX_EXPORT Rect operator+(const Rect& lhs, const Vector2d& rhs);
 202 GFX_EXPORT Rect operator-(const Rect& lhs, const Vector2d& rhs);
 203
 204 inline Rect operator+(const Vector2d& lhs, const Rect& rhs) {
 205   return rhs + lhs;
 206 }
 207
 208 GFX_EXPORT Rect IntersectRects(const Rect& a, const Rect& b);
 209 GFX_EXPORT Rect UnionRects(const Rect& a, const Rect& b);
 210 GFX_EXPORT Rect SubtractRects(const Rect& a, const Rect& b);
 211
 212 // Constructs a rectangle with |p1| and |p2| as opposite corners.
 213 //
 214 // This could also be thought of as "the smallest rect that contains both
 215 // points", except that we consider points on the right/bottom edges of the
 216 // rect to be outside the rect.  So technically one or both points will not be
 217 // contained within the rect, because they will appear on one of these edges.
 218 GFX_EXPORT Rect BoundingRect(const Point& p1, const Point& p2);
 219
 220 inline Rect ScaleToEnclosingRect(const Rect& rect,
 221                                  float x_scale,
 222                                  float y_scale) {
 223   if (x_scale == 1.f && y_scale == 1.f)
 224     return rect;
 225   // These next functions cast instead of using e.g. ToFlooredInt() because we
 226   // haven't checked to ensure that the clamping behavior of the helper
 227   // functions doesn't degrade performance, and callers shouldn't be passing
 228   // values that cause overflow anyway.
 229   DCHECK(base::IsValueInRangeForNumericType<int>(
 230       std::floor(rect.x() * x_scale)));
 231   DCHECK(base::IsValueInRangeForNumericType<int>(
 232       std::floor(rect.y() * y_scale)));
 233   DCHECK(base::IsValueInRangeForNumericType<int>(
 234       std::ceil(rect.right() * x_scale)));
 235   DCHECK(base::IsValueInRangeForNumericType<int>(
 236       std::ceil(rect.bottom() * y_scale)));
 237   int x = static_cast<int>(std::floor(rect.x() * x_scale));
 238   int y = static_cast<int>(std::floor(rect.y() * y_scale));
 239   int r = rect.width() == 0 ?
 240       x : static_cast<int>(std::ceil(rect.right() * x_scale));
 241   int b = rect.height() == 0 ?
 242       y : static_cast<int>(std::ceil(rect.bottom() * y_scale));
 243   return Rect(x, y, r - x, b - y);
 244 }
 245
 246 inline Rect ScaleToEnclosingRect(const Rect& rect, float scale) {
 247   return ScaleToEnclosingRect(rect, scale, scale);
 248 }
 249
 250 inline Rect ScaleToEnclosedRect(const Rect& rect,
 251                                 float x_scale,
 252                                 float y_scale) {
 253   if (x_scale == 1.f && y_scale == 1.f)
 254     return rect;
 255   DCHECK(base::IsValueInRangeForNumericType<int>(
 256       std::ceil(rect.x() * x_scale)));
 257   DCHECK(base::IsValueInRangeForNumericType<int>(
 258       std::ceil(rect.y() * y_scale)));
 259   DCHECK(base::IsValueInRangeForNumericType<int>(
 260       std::floor(rect.right() * x_scale)));
 261   DCHECK(base::IsValueInRangeForNumericType<int>(
 262       std::floor(rect.bottom() * y_scale)));
 263   int x = static_cast<int>(std::ceil(rect.x() * x_scale));
 264   int y = static_cast<int>(std::ceil(rect.y() * y_scale));
 265   int r = rect.width() == 0 ?
 266       x : static_cast<int>(std::floor(rect.right() * x_scale));
 267   int b = rect.height() == 0 ?
 268       y : static_cast<int>(std::floor(rect.bottom() * y_scale));
 269   return Rect(x, y, r - x, b - y);
 270 }
 271
 272 inline Rect ScaleToEnclosedRect(const Rect& rect, float scale) {
 273   return ScaleToEnclosedRect(rect, scale, scale);
 274 }
 275
 276 // This is declared here for use in gtest-based unit tests but is defined in
 277 // the gfx_test_support target. Depend on that to use this in your unit test.
 278 // This should not be used in production code - call ToString() instead.
 279 void PrintTo(const Rect& rect, ::std::ostream* os);
 280
 281 }  // namespace gfx
 282
 283 #endif  // UI_GFX_GEOMETRY_RECT_H_