ui/gfx/geometry/vector2d_f.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 float vector class.  This class is used to indicate a
   6 // distance in two dimensions between two points. Subtracting two points should
   7 // produce a vector, and adding a vector to a point produces the point at the
   8 // vector's distance from the original point.
   9
  10 #ifndef UI_GFX_GEOMETRY_VECTOR2D_F_H_
  11 #define UI_GFX_GEOMETRY_VECTOR2D_F_H_
  12
  13 #include <iosfwd>
  14 #include <string>
  15
  16 #include "ui/gfx/gfx_export.h"
  17
  18 namespace gfx {
  19
  20 class GFX_EXPORT Vector2dF {
  21  public:
  22   Vector2dF() : x_(0), y_(0) {}
  23   Vector2dF(float x, float y) : x_(x), y_(y) {}
  24
  25   float x() const { return x_; }
  26   void set_x(float x) { x_ = x; }
  27
  28   float y() const { return y_; }
  29   void set_y(float y) { y_ = y; }
  30
  31   // True if both components of the vector are 0.
  32   bool IsZero() const;
  33
  34   // Add the components of the |other| vector to the current vector.
  35   void Add(const Vector2dF& other);
  36   // Subtract the components of the |other| vector from the current vector.
  37   void Subtract(const Vector2dF& other);
  38
  39   void operator+=(const Vector2dF& other) { Add(other); }
  40   void operator-=(const Vector2dF& other) { Subtract(other); }
  41
  42   void SetToMin(const Vector2dF& other) {
  43     x_ = x_ <= other.x_ ? x_ : other.x_;
  44     y_ = y_ <= other.y_ ? y_ : other.y_;
  45   }
  46
  47   void SetToMax(const Vector2dF& other) {
  48     x_ = x_ >= other.x_ ? x_ : other.x_;
  49     y_ = y_ >= other.y_ ? y_ : other.y_;
  50   }
  51
  52   // Gives the square of the diagonal length of the vector.
  53   double LengthSquared() const;
  54   // Gives the diagonal length of the vector.
  55   float Length() const;
  56
  57   // Scale the x and y components of the vector by |scale|.
  58   void Scale(float scale) { Scale(scale, scale); }
  59   // Scale the x and y components of the vector by |x_scale| and |y_scale|
  60   // respectively.
  61   void Scale(float x_scale, float y_scale);
  62
  63   std::string ToString() const;
  64
  65  private:
  66   float x_;
  67   float y_;
  68 };
  69
  70 inline bool operator==(const Vector2dF& lhs, const Vector2dF& rhs) {
  71   return lhs.x() == rhs.x() && lhs.y() == rhs.y();
  72 }
  73
  74 inline bool operator!=(const Vector2dF& lhs, const Vector2dF& rhs) {
  75   return !(lhs == rhs);
  76 }
  77
  78 inline Vector2dF operator-(const Vector2dF& v) {
  79   return Vector2dF(-v.x(), -v.y());
  80 }
  81
  82 inline Vector2dF operator+(const Vector2dF& lhs, const Vector2dF& rhs) {
  83   Vector2dF result = lhs;
  84   result.Add(rhs);
  85   return result;
  86 }
  87
  88 inline Vector2dF operator-(const Vector2dF& lhs, const Vector2dF& rhs) {
  89   Vector2dF result = lhs;
  90   result.Add(-rhs);
  91   return result;
  92 }
  93
  94 // Return the cross product of two vectors.
  95 GFX_EXPORT double CrossProduct(const Vector2dF& lhs, const Vector2dF& rhs);
  96
  97 // Return the dot product of two vectors.
  98 GFX_EXPORT double DotProduct(const Vector2dF& lhs, const Vector2dF& rhs);
  99
 100 // Return a vector that is |v| scaled by the given scale factors along each
 101 // axis.
 102 GFX_EXPORT Vector2dF ScaleVector2d(const Vector2dF& v,
 103                                    float x_scale,
 104                                    float y_scale);
 105
 106 // Return a vector that is |v| scaled by the given scale factor.
 107 inline Vector2dF ScaleVector2d(const Vector2dF& v, float scale) {
 108   return ScaleVector2d(v, scale, scale);
 109 }
 110
 111 // This is declared here for use in gtest-based unit tests but is defined in
 112 // the gfx_test_support target. Depend on that to use this in your unit test.
 113 // This should not be used in production code - call ToString() instead.
 114 void PrintTo(const Vector2dF& vector, ::std::ostream* os);
 115
 116 }  // namespace gfx
 117
 118 #endif // UI_GFX_GEOMETRY_VECTOR2D_F_H_