* fix Quaternion::setFromTwoVectors (thanks to "benv" from the forum)

* extend PartialRedux::cross() to any matrix sizes with automatic
  vectorization when possible
* unit tests: add "geo_" prefix to all unit tests related to the
  geometry module and start splitting the big "geometry.cpp" tests to
  multiple smaller ones (also include new tests)

2 files changed, 47 insertions, 2 deletions

diff --git a/Eigen/src/Geometry/OrthoMethods.h b/Eigen/src/Geometry/OrthoMethods.h
index 047152d0b..e22df114a 100644
--- a/Eigen/src/Geometry/OrthoMethods.h
+++ b/Eigen/src/Geometry/OrthoMethods.h
@@ -1,7 +1,7 @@
 // This file is part of Eigen, a lightweight C++ template library
 // for linear algebra. Eigen itself is part of the KDE project.
 //
-// Copyright (C) 2008 Gael Guennebaud <g.gael@free.fr>
+// Copyright (C) 2008-2009 Gael Guennebaud <g.gael@free.fr>
 // Copyright (C) 2006-2008 Benoit Jacob <jacob.benoit.1@gmail.com>
 //
 // Eigen is free software; you can redistribute it and/or
@@ -50,6 +50,42 @@ MatrixBase<Derived>::cross(const MatrixBase<OtherDerived>& other) const
   );
 }
 
+/** \returns a matrix expression of the cross product of each column or row
+  * of the referenced expression with the \a other vector.
+  *
+  * The referenced matrix must have one dimension equal to 3.
+  * The result matrix has the same dimensions than the referenced one.
+  *
+  * \geometry_module
+  *
+  * \sa MatrixBase::cross() */
+template<typename ExpressionType, int Direction>
+template<typename OtherDerived>
+const typename PartialRedux<ExpressionType,Direction>::CrossReturnType
+PartialRedux<ExpressionType,Direction>::cross(const MatrixBase<OtherDerived>& other) const
+{
+  EIGEN_STATIC_ASSERT_VECTOR_SPECIFIC_SIZE(OtherDerived,3)
+  EIGEN_STATIC_ASSERT((ei_is_same_type<Scalar, typename OtherDerived::Scalar>::ret),
+    YOU_MIXED_DIFFERENT_NUMERIC_TYPES__YOU_NEED_TO_USE_THE_CAST_METHOD_OF_MATRIXBASE_TO_CAST_NUMERIC_TYPES_EXPLICITLY)
+
+  CrossReturnType res(_expression().rows(),_expression().cols());
+  if(Direction==Vertical)
+  {
+    ei_assert(CrossReturnType::RowsAtCompileTime==3 && "the matrix must have exactly 3 rows");
+    res.row(0) = _expression().row(1) * other.coeff(2) - _expression().row(2) * other.coeff(1);
+    res.row(1) = _expression().row(2) * other.coeff(0) - _expression().row(0) * other.coeff(2);
+    res.row(2) = _expression().row(0) * other.coeff(1) - _expression().row(1) * other.coeff(0);
+  }
+  else
+  {
+    ei_assert(CrossReturnType::ColsAtCompileTime==3 && "the matrix must have exactly 3 columns");
+    res.col(0) = _expression().col(1) * other.coeff(2) - _expression().col(2) * other.coeff(1);
+    res.col(1) = _expression().col(2) * other.coeff(0) - _expression().col(0) * other.coeff(2);
+    res.col(2) = _expression().col(0) * other.coeff(1) - _expression().col(1) * other.coeff(0);
+  }
+  return res;
+}
+
 template<typename Derived, int Size = Derived::SizeAtCompileTime>
 struct ei_unitOrthogonal_selector
 {
diff --git a/Eigen/src/Geometry/Quaternion.h b/Eigen/src/Geometry/Quaternion.h
index e72ce814f..0305fe176 100644
--- a/Eigen/src/Geometry/Quaternion.h
+++ b/Eigen/src/Geometry/Quaternion.h
@@ -345,7 +345,6 @@ inline Quaternion<Scalar>& Quaternion<Scalar>::setFromTwoVectors(const MatrixBas
 {
   Vector3 v0 = a.normalized();
   Vector3 v1 = b.normalized();
-  Vector3 axis = v0.cross(v1);
   Scalar c = v0.dot(v1);
 
   // if dot == 1, vectors are the same
@@ -353,7 +352,17 @@ inline Quaternion<Scalar>& Quaternion<Scalar>::setFromTwoVectors(const MatrixBas
   {
     // set to identity
     this->w() = 1; this->vec().setZero();
+    return *this;
   }
+  // if dot == -1, vectors are opposites
+  if (ei_isApprox(c,Scalar(-1)))
+  {
+    this->vec() = v0.unitOrthogonal();
+    this->w() = 0;
+    return *this;
+  }
+
+  Vector3 axis = v0.cross(v1);
   Scalar s = ei_sqrt((Scalar(1)+c)*Scalar(2));
   Scalar invs = Scalar(1)/s;
   this->vec() = axis * invs;