michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim:set ts=2 sw=2 sts=2 et cindent: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef ThreeDPoint_h_
michael@0: #define ThreeDPoint_h_
michael@0: 
michael@0: #include <cmath>
michael@0: #include <algorithm>
michael@0: 
michael@0: namespace mozilla {
michael@0: 
michael@0: namespace dom {
michael@0: 
michael@0: struct ThreeDPoint {
michael@0:   ThreeDPoint()
michael@0:     : x(0.)
michael@0:     , y(0.)
michael@0:     , z(0.)
michael@0:   {
michael@0:   }
michael@0:   ThreeDPoint(double aX, double aY, double aZ)
michael@0:     : x(aX)
michael@0:     , y(aY)
michael@0:     , z(aZ)
michael@0:   {
michael@0:   }
michael@0: 
michael@0:   double Magnitude() const
michael@0:   {
michael@0:     return sqrt(x * x + y * y + z * z);
michael@0:   }
michael@0: 
michael@0:   void Normalize()
michael@0:   {
michael@0:     // Normalize with the maximum norm first to avoid overflow and underflow.
michael@0:     double invMax = 1 / MaxNorm();
michael@0:     x *= invMax;
michael@0:     y *= invMax;
michael@0:     z *= invMax;
michael@0: 
michael@0:     double invDistance = 1 / Magnitude();
michael@0:     x *= invDistance;
michael@0:     y *= invDistance;
michael@0:     z *= invDistance;
michael@0:   }
michael@0: 
michael@0:   ThreeDPoint CrossProduct(const ThreeDPoint& rhs) const
michael@0:   {
michael@0:     return ThreeDPoint(y * rhs.z - z * rhs.y,
michael@0:                        z * rhs.x - x * rhs.z,
michael@0:                        x * rhs.y - y * rhs.x);
michael@0:   }
michael@0: 
michael@0:   double DotProduct(const ThreeDPoint& rhs)
michael@0:   {
michael@0:     return x * rhs.x + y * rhs.y + z * rhs.z;
michael@0:   }
michael@0: 
michael@0:   bool IsZero() const
michael@0:   {
michael@0:     return x == 0 && y == 0 && z == 0;
michael@0:   }
michael@0: 
michael@0:   // For comparing two vectors of close to unit magnitude.
michael@0:   bool FuzzyEqual(const ThreeDPoint& other);
michael@0: 
michael@0:   double x, y, z;
michael@0: 
michael@0: private:
michael@0:   double MaxNorm() const
michael@0:   {
michael@0:     return std::max(fabs(x), std::max(fabs(y), fabs(z)));
michael@0:   }
michael@0: };
michael@0: 
michael@0: ThreeDPoint operator-(const ThreeDPoint& lhs, const ThreeDPoint& rhs);
michael@0: ThreeDPoint operator*(const ThreeDPoint& lhs, const ThreeDPoint& rhs);
michael@0: ThreeDPoint operator*(const ThreeDPoint& lhs, const double rhs);
michael@0: bool operator==(const ThreeDPoint& lhs, const ThreeDPoint& rhs);
michael@0: 
michael@0: }
michael@0: }
michael@0: 
michael@0: #endif
michael@0: