Use SkMatrix44 for the underlying implementation of ui::Transform

ui/gfx/point3.h

+// Copyright (c) 2011 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.
+
+#ifndef UI_GFX_POINT3_H_
+#define UI_GFX_POINT3_H_
+#pragma once
+
+#include <cmath>
+
+#include "ui/gfx/point.h"
+
+namespace gfx {
+
+// A point has an x, y and z coordinate.
+class Point3f {
+ public:
+  Point3f() : x_(0), y_(0), z_(0) {}
+
+  Point3f(float x, float y, float z) : x_(x), y_(y), z_(z) {}
+
+  Point3f(const Point& point) : x_(point.x()), y_(point.y()), z_(0) {}
+
+  ~Point3f() {}
+
+  float x() const { return x_; }
+  float y() const { return y_; }
+  float z() const { return z_; }
+
+  void set_x(float x) { x_ = x; }
+  void set_y(float y) { y_ = y; }
+  void set_z(float z) { z_ = z; }
+
+  void SetPoint(float x, float y, float z) {
+    x_ = x;
+    y_ = y;
+    z_ = z;
+  }
+
+  // Returns the squared euclidean distance between two points.
+  float SquaredDistanceTo(const Point3f& other) const {
+    float dx = x_ - other.x_;
+    float dy = y_ - other.y_;
+    float dz = z_ - other.z_;
+    return dx * dx + dy * dy + dz * dz;
+  }
+
+  Point AsPoint() const {
+    return Point(static_cast<int>(std::floor(x_)),
+                 static_cast<int>(std::floor(y_)));
+  }
+
+ private:
+  float x_;
+  float y_;
+  float z_;
+
+  // copy/assign are allowed.
+};
+
+}  // namespace gfx
+
+#endif  // UI_GFX_POINT3_H_