Fix numerous doxygen shortcomings, and workaround some clang -Wdocumentation warnings

Eigen/src/Geometry/Hyperplane.h

@@ -22,8 +22,8 @@ namespace Eigen {
   * A hyperplane is an affine subspace of dimension n-1 in a space of dimension n.
   * For example, a hyperplane in a plane is a line; a hyperplane in 3-space is a plane.
   *
-  * \param _Scalar the scalar type, i.e., the type of the coefficients
-  * \param _AmbientDim the dimension of the ambient space, can be a compile time value or Dynamic.
+  * \tparam _Scalar the scalar type, i.e., the type of the coefficients
+  * \tparam _AmbientDim the dimension of the ambient space, can be a compile time value or Dynamic.
   *             Notice that the dimension of the hyperplane is _AmbientDim-1.
   *
   * This class represents an hyperplane as the zero set of the implicit equation

Eigen/src/Geometry/ParametrizedLine.h

@@ -23,8 +23,8 @@ namespace Eigen {
   * direction vector \f$ \mathbf{d} \f$ such that the line corresponds to
   * the set \f$ l(t) = \mathbf{o} + t \mathbf{d} \f$, \f$ t \in \mathbf{R} \f$.
   *
-  * \param _Scalar the scalar type, i.e., the type of the coefficients
-  * \param _AmbientDim the dimension of the ambient space, can be a compile time value or Dynamic.
+  * \tparam _Scalar the scalar type, i.e., the type of the coefficients
+  * \tparam _AmbientDim the dimension of the ambient space, can be a compile time value or Dynamic.
   */
 template <typename _Scalar, int _AmbientDim, int _Options>
 class ParametrizedLine

Eigen/src/Geometry/Rotation2D.h

@@ -18,7 +18,7 @@ namespace Eigen {
   *
   * \brief Represents a rotation/orientation in a 2 dimensional space.
   *
-  * \param _Scalar the scalar type, i.e., the type of the coefficients
+  * \tparam _Scalar the scalar type, i.e., the type of the coefficients
   *
   * This class is equivalent to a single scalar representing a counter clock wise rotation
   * as a single angle in radian. It provides some additional features such as the automatic

Eigen/src/Geometry/RotationBase.h

@@ -22,8 +22,8 @@ struct rotation_base_generic_product_selector;
   *
   * \brief Common base class for compact rotation representations
   *
-  * \param Derived is the derived type, i.e., a rotation type
-  * \param _Dim the dimension of the space
+  * \tparam Derived is the derived type, i.e., a rotation type
+  * \tparam _Dim the dimension of the space
   */
 template<typename Derived, int _Dim>
 class RotationBase
@@ -164,8 +164,8 @@ namespace internal {
   *
   * Helper function to return an arbitrary rotation object to a rotation matrix.
   *
-  * \param Scalar the numeric type of the matrix coefficients
-  * \param Dim the dimension of the current space
+  * \tparam Scalar the numeric type of the matrix coefficients
+  * \tparam Dim the dimension of the current space
   *
   * It returns a Dim x Dim fixed size matrix.
   *

Eigen/src/Geometry/Scaling.h

@@ -18,7 +18,7 @@ namespace Eigen {
   *
   * \brief Represents a generic uniform scaling transformation
   *
-  * \param _Scalar the scalar type, i.e., the type of the coefficients.
+  * \tparam _Scalar the scalar type, i.e., the type of the coefficients.
   *
   * This class represent a uniform scaling transformation. It is the return
   * type of Scaling(Scalar), and most of the time this is the only way it

Eigen/src/Geometry/Translation.h

@@ -18,8 +18,8 @@ namespace Eigen {
   *
   * \brief Represents a translation transformation
   *
-  * \param _Scalar the scalar type, i.e., the type of the coefficients.
-  * \param _Dim the  dimension of the space, can be a compile time value or Dynamic
+  * \tparam _Scalar the scalar type, i.e., the type of the coefficients.
+  * \tparam _Dim the  dimension of the space, can be a compile time value or Dynamic
   *
   * \note This class is not aimed to be used to store a translation transformation,
   * but rather to make easier the constructions and updates of Transform objects.