ui/gfx/point_base.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 #ifndef UI_GFX_POINT_BASE_H_
   6 #define UI_GFX_POINT_BASE_H_
   7
   8 #include <string>
   9
  10 #include "base/compiler_specific.h"
  11 #include "build/build_config.h"
  12 #include "ui/gfx/gfx_export.h"
  13
  14 namespace gfx {
  15
  16 // A point has an x and y coordinate.
  17 template<typename Class, typename Type, typename VectorClass>
  18 class GFX_EXPORT PointBase {
  19  public:
  20   Type x() const { return x_; }
  21   Type y() const { return y_; }
  22
  23   void SetPoint(Type x, Type y) {
  24     x_ = x;
  25     y_ = y;
  26   }
  27
  28   void set_x(Type x) { x_ = x; }
  29   void set_y(Type y) { y_ = y; }
  30
  31   void Offset(Type delta_x, Type delta_y) {
  32     x_ += delta_x;
  33     y_ += delta_y;
  34   }
  35
  36   void operator+=(const VectorClass& vector) {
  37     x_ += vector.x();
  38     y_ += vector.y();
  39   }
  40
  41   void operator-=(const VectorClass& vector) {
  42     x_ -= vector.x();
  43     y_ -= vector.y();
  44   }
  45
  46   void SetToMin(const Class& other) {
  47     x_ = x_ <= other.x_ ? x_ : other.x_;
  48     y_ = y_ <= other.y_ ? y_ : other.y_;
  49   }
  50
  51   void SetToMax(const Class& other) {
  52     x_ = x_ >= other.x_ ? x_ : other.x_;
  53     y_ = y_ >= other.y_ ? y_ : other.y_;
  54   }
  55
  56   bool IsOrigin() const {
  57     return x_ == 0 && y_ == 0;
  58   }
  59
  60   VectorClass OffsetFromOrigin() const {
  61     return VectorClass(x_, y_);
  62   }
  63
  64   // A point is less than another point if its y-value is closer
  65   // to the origin. If the y-values are the same, then point with
  66   // the x-value closer to the origin is considered less than the
  67   // other.
  68   // This comparison is required to use Point in sets, or sorted
  69   // vectors.
  70   bool operator<(const Class& rhs) const {
  71     return (y_ == rhs.y_) ? (x_ < rhs.x_) : (y_ < rhs.y_);
  72   }
  73
  74  protected:
  75   PointBase(Type x, Type y) : x_(x), y_(y) {}
  76   // Destructor is intentionally made non virtual and protected.
  77   // Do not make this public.
  78   ~PointBase() {}
  79
  80  private:
  81   Type x_;
  82   Type y_;
  83 };
  84
  85 }  // namespace gfx
  86
  87 #endif  // UI_GFX_POINT_BASE_H_