ui: Add the gfx::Vector3dF class.

ui/gfx/vector3d_f.h

Index: ui/gfx/vector3d_f.h
diff --git a/ui/gfx/vector3d_f.h b/ui/gfx/vector3d_f.h
new file mode 100644
index 0000000000000000000000000000000000000000..a2845f89267880e28b4634df450471e30c520402
--- /dev/null
+++ b/ui/gfx/vector3d_f.h
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+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Defines a simple float vector class.  This class is used to indicate a
+// distance in two dimensions between two points. Subtracting two points should
+// produce a vector, and adding a vector to a point produces the point at the
+// vector's distance from the original point.
+
+#ifndef UI_GFX_VECTOR3D_F_H_
+#define UI_GFX_VECTOR3D_F_H_
+
+#include <string>
+
+#include "ui/base/ui_export.h"
+#include "ui/gfx/vector2d_f.h"
+
+namespace gfx {
+
+class UI_EXPORT Vector3dF {
+ public:
+  Vector3dF();
+  Vector3dF(float x, float y, float z);
+
+  explicit Vector3dF(const Vector2dF& other);
+
+  float x() const { return x_; }
+  void set_x(float x) { x_ = x; }
+
+  float y() const { return y_; }
+  void set_y(float y) { y_ = y; }
+
+  float z() const { return z_; }
+  void set_z(float z) { z_ = z; }
+
+  // True if all components of the vector are 0.
+  bool IsZero() const;
+
+  // Add the components of the |other| vector to the current vector.
+  void Add(const Vector3dF& other);
+  // Subtract the components of the |other| vector from the current vector.
+  void Subtract(const Vector3dF& other);
+
+  void operator+=(const Vector3dF& other) { Add(other); }
+  void operator-=(const Vector3dF& other) { Subtract(other); }
+
+  // Gives the square of the diagonal length of the vector.
+  double LengthSquared() const;
+  // Gives the diagonal length of the vector.
+  float Length() const;
+
+  // Scale all components of the vector by |scale|.
+  void Scale(float scale) { Scale(scale, scale, scale); }
+  // Scale the each component of the vector by the given scale factors.
+  void Scale(float x_scale, float y_scale, float z_scale);
+
+  // Take the cross product of this vector with |other| and become the result.
+  void Cross(const Vector3dF& other);
+
+  std::string ToString() const;
+
+ private:
+  float x_;
+  float y_;
+  float z_;
+};
+
+inline bool operator==(const Vector3dF& lhs, const Vector3dF& rhs) {
+  return lhs.x() == rhs.x() && lhs.y() == rhs.y() && lhs.z() == rhs.z();
+}
+
+inline Vector3dF operator-(const Vector3dF& v) {
+  return Vector3dF(-v.x(), -v.y(), -v.z());
+}
+
+inline Vector3dF operator+(const Vector3dF& lhs, const Vector3dF& rhs) {
+  Vector3dF result = lhs;
+  result.Add(rhs);
+  return result;
+}
+
+inline Vector3dF operator-(const Vector3dF& lhs, const Vector3dF& rhs) {
+  Vector3dF result = lhs;
+  result.Add(-rhs);
+  return result;
+}
+
+// Return the cross product of two vectors.
+inline Vector3dF CrossProduct(const Vector3dF& lhs, const Vector3dF& rhs) {
+  Vector3dF result = lhs;
+  result.Cross(rhs);
+  return result;
+}
+
+// Return the dot product of two vectors.
+UI_EXPORT float DotProduct(const Vector3dF& lhs, const Vector3dF& rhs);

[Peter Kasting, 2012/11/01 00:24:58]

Should we add this for 2D vectors too?

[danakj, 2012/11/01 00:39:53]

We could, but without any call sites?

[Peter Kasting, 2012/11/01 01:33:28]

Just didn't know if you'd need it.  If not don't worry about it.

[danakj, 2012/11/01 01:36:23]

Ya, only code doing dot products for cc/ at the moment is doing it with 3d
points. :)

+
+
+}  // namespace gfx
+
+#endif // UI_GFX_VECTOR3D_F_H_