From 2600ba173168b6e9b32c713f2c217d322aab043e Mon Sep 17 00:00:00 2001
From: Gael Guennebaud <g.gael@free.fr>
Date: Sat, 10 Dec 2011 12:17:42 +0100
Subject: [PATCH] feature 297: s/intersectionPoint/pointAt, fix documentation,
 add a unit test

---
 Eigen/src/Geometry/ParametrizedLine.h | 18 +++++++-----------
 test/geo_parametrizedline.cpp         | 11 +++++++++++
 2 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/Eigen/src/Geometry/ParametrizedLine.h b/Eigen/src/Geometry/ParametrizedLine.h
index 4e4d52f9b..ddf6e7b8c 100644
--- a/Eigen/src/Geometry/ParametrizedLine.h
+++ b/Eigen/src/Geometry/ParametrizedLine.h
@@ -106,22 +106,17 @@ public:
   VectorType projection(const VectorType& p) const
   { return origin() + direction().dot(p-origin()) * direction(); }
 
-  /** \returns the point at parameter t along the line */
-  VectorType intersectionPoint( Scalar t ) const;
+  VectorType pointAt( Scalar t ) const;
   
-  /** \returns parameter t of the intersection of the line with hyperplane */
   template <int OtherOptions>
   Scalar intersectionParameter(const Hyperplane<_Scalar, _AmbientDim, OtherOptions>& hyperplane) const;
  
-  /** \returns parameter t of the intersection of the line with hyperplane. (maintained for API compatablity) */
   template <int OtherOptions>
   Scalar intersection(const Hyperplane<_Scalar, _AmbientDim, OtherOptions>& hyperplane) const;
   
-  /** \returns the intersection point of the line with hyperplane */
   template <int OtherOptions>
   VectorType intersectionPoint(const Hyperplane<_Scalar, _AmbientDim, OtherOptions>& hyperplane) const;
 
-
   /** \returns \c *this with scalar type casted to \a NewScalarType
     *
     * Note that if \a NewScalarType is equal to the current scalar type of \c *this
@@ -168,16 +163,16 @@ inline ParametrizedLine<_Scalar, _AmbientDim,_Options>::ParametrizedLine(const H
   origin() = -hyperplane.normal()*hyperplane.offset();
 }
 
-/** \returns the point at t along this line
+/** \returns the point at \a t along this line
   */
 template <typename _Scalar, int _AmbientDim, int _Options>
 inline typename ParametrizedLine<_Scalar, _AmbientDim,_Options>::VectorType
-ParametrizedLine<_Scalar, _AmbientDim,_Options>::intersectionPoint( _Scalar t ) const
+ParametrizedLine<_Scalar, _AmbientDim,_Options>::pointAt( _Scalar t ) const
 {
   return origin() + (direction()*t); 
 }
 
-/** \returns the parameter value of the intersection between \c *this and the given hyperplane
+/** \returns the parameter value of the intersection between \c *this and the given \a hyperplane
   */
 template <typename _Scalar, int _AmbientDim, int _Options>
 template <int OtherOptions>
@@ -188,7 +183,8 @@ inline _Scalar ParametrizedLine<_Scalar, _AmbientDim,_Options>::intersectionPara
 }
 
 
-/** \returns the parameter value of the intersection between \c *this and the given hyperplane
+/** \deprecated use intersectionParameter()
+  * \returns the parameter value of the intersection between \c *this and the given \a hyperplane
   */
 template <typename _Scalar, int _AmbientDim, int _Options>
 template <int OtherOptions>
@@ -204,7 +200,7 @@ template <int OtherOptions>
 inline typename ParametrizedLine<_Scalar, _AmbientDim,_Options>::VectorType
 ParametrizedLine<_Scalar, _AmbientDim,_Options>::intersectionPoint(const Hyperplane<_Scalar, _AmbientDim, OtherOptions>& hyperplane) const
 {
-  return intersectionPoint(intersectionParameter(hyperplane)); 
+  return pointAt(intersectionParameter(hyperplane));
 }
 
 #endif // EIGEN_PARAMETRIZEDLINE_H
diff --git a/test/geo_parametrizedline.cpp b/test/geo_parametrizedline.cpp
index 13f98fdd6..a289e70de 100644
--- a/test/geo_parametrizedline.cpp
+++ b/test/geo_parametrizedline.cpp
@@ -40,6 +40,7 @@ template<typename LineType> void parametrizedline(const LineType& _line)
   typedef Matrix<Scalar, LineType::AmbientDimAtCompileTime, 1> VectorType;
   typedef Matrix<Scalar, LineType::AmbientDimAtCompileTime,
                          LineType::AmbientDimAtCompileTime> MatrixType;
+  typedef Hyperplane<Scalar,LineType::AmbientDimAtCompileTime> HyperplaneType;
 
   VectorType p0 = VectorType::Random(dim);
   VectorType p1 = VectorType::Random(dim);
@@ -64,6 +65,16 @@ template<typename LineType> void parametrizedline(const LineType& _line)
   VERIFY_IS_APPROX(hp1f.template cast<Scalar>(),l0);
   ParametrizedLine<Scalar,Dim> hp1d = l0.template cast<Scalar>();
   VERIFY_IS_APPROX(hp1d.template cast<Scalar>(),l0);
+
+  // intersections
+  VectorType p2 = VectorType::Random(dim);
+  VectorType n2 = VectorType::Random(dim).normalized();
+  HyperplaneType hp(p2,n2);
+  Scalar t = l0.intersectionParameter(hp);
+  VectorType pi = l0.pointAt(t);
+  VERIFY_IS_MUCH_SMALLER_THAN(hp.signedDistance(pi), RealScalar(1));
+  VERIFY_IS_MUCH_SMALLER_THAN(l0.distance(pi), RealScalar(1));
+  VERIFY_IS_APPROX(l0.intersectionPoint(hp), pi);
 }
 
 template<typename Scalar> void parametrizedline_alignment()