--- /dev/null
+/* -*- C++ -*- ------------------------------------------------------------
+
+Copyright (c) 2007 Jesse Anders and Demian Nave http://cmldev.net/
+
+The Configurable Math Library (CML) is distributed under the terms of the
+Boost Software License, v1.0 (see cml/LICENSE for details).
+
+ *-----------------------------------------------------------------------*/
+/** @file
+ * @brief
+ *
+ * Defines promotions for matrices used in matrix/matrix or matrix/scalar
+ * expressions.
+ *
+ * @sa UnaryMat4_TOp
+ * @sa BinaryMat4_TOp
+ */
+
+#ifndef matrix_promotions_h
+#define matrix_promotions_h
+
+#include <cml/core/cml_meta.h>
+#include <cml/et/scalar_promotions.h>
+#include <cml/et/array_promotions.h>
+#include <cml/fixed.h>
+#include <cml/dynamic.h>
+
+/* This is used below to create a more meaningful compile-time error when
+ * either argument to OuterPromote has the wrong orientation.
+ */
+struct outer_promote_expects_properly_oriented_args_error;
+
+namespace cml {
+namespace et {
+
+/* Default matrix type promotion template. */
+template<typename LeftT, typename RightT> struct MatrixPromote;
+
+/** Type promotion for two matrix types.
+ *
+ * @note This always uses the basis orientation of the left-hand matrix.
+ * @bug This always uses the basis orientation of the left-hand matrix,
+ * which is not always correct.
+ */
+template<typename E1, class AT1, typename L1, typename BO1,
+ typename E2, class AT2, typename L2, typename BO2>
+struct MatrixPromote< cml::matrix<E1,AT1,BO1,L1>, cml::matrix<E2,AT2,BO2,L2> >
+{
+ /* Promote the arrays: */
+ typedef typename ArrayPromote<
+ typename cml::matrix<E1,AT1,BO1,L1>::array_type,
+ typename cml::matrix<E2,AT2,BO2,L2>::array_type
+ >::type promoted_array;
+
+ /* The deduced matrix result type: */
+ typedef cml::matrix<
+ typename promoted_array::value_type,
+ typename promoted_array::generator_type,
+ BO1,
+ typename promoted_array::layout
+ > type;
+
+ /* The deduced temporary type: */
+ typedef typename type::temporary_type temporary_type;
+};
+
+/**
+ * NOTE: MatrixPromote* are somewhat ad hoc, and were added to
+ * simplify the code for matrix slerp/squad/etc.
+ */
+
+/** Type promotion for two matrix types. */
+template < class Mat1_T, class Mat2_T >
+struct MatrixPromote2
+{
+ typedef typename MatrixPromote<
+ typename Mat1_T::temporary_type, typename Mat2_T::temporary_type
+ >::temporary_type temporary_type;
+ typedef typename temporary_type::value_type value_type;
+};
+
+/** Type promotion for three matrix types. */
+template < class Mat1_T, class Mat2_T, class Mat3_T >
+struct MatrixPromote3
+{
+ typedef typename MatrixPromote<
+ typename Mat1_T::temporary_type,
+ typename MatrixPromote<
+ typename Mat2_T::temporary_type, typename Mat3_T::temporary_type
+ >::temporary_type
+ >::temporary_type temporary_type;
+ typedef typename temporary_type::value_type value_type;
+};
+
+/** Type promotion for four matrix types. */
+template < class Mat1_T, class Mat2_T, class Mat3_T, class Mat4_T >
+struct MatrixPromote4
+{
+ typedef typename MatrixPromote<
+ typename Mat1_T::temporary_type,
+ typename MatrixPromote<
+ typename Mat2_T::temporary_type,
+ typename MatrixPromote<
+ typename Mat3_T::temporary_type,
+ typename Mat4_T::temporary_type
+ >::temporary_type
+ >::temporary_type
+ >::temporary_type temporary_type;
+ typedef typename temporary_type::value_type value_type;
+};
+
+/** Type promotion for a matrix and a scalar. */
+template<typename E, class AT, typename BO, typename L, typename S>
+struct MatrixPromote<cml::matrix<E,AT,BO,L>, S>
+{
+ /* The deduced matrix result type (the array type is the same): */
+ typedef cml::matrix<typename ScalarPromote<E,S>::type, AT, BO, L> type;
+
+ /* The deduced temporary type: */
+ typedef typename type::temporary_type temporary_type;
+};
+
+/** Type promotion for a scalar and a matrix. */
+template<typename S, typename E, class AT, typename BO, typename L>
+struct MatrixPromote<S, cml::matrix<E,AT,BO,L> >
+{
+ /* The deduced matrix result type (the array type is the same): */
+ typedef cml::matrix<typename ScalarPromote<S,E>::type, AT, BO, L> type;
+
+ /* The deduced temporary type: */
+ typedef typename type::temporary_type temporary_type;
+};
+
+/** Type promotion for outer product. */
+template<typename E1, class AT1, typename E2, class AT2>
+struct MatrixPromote< cml::vector<E1,AT1>, cml::vector<E2,AT2> >
+{
+ typedef cml::vector<E1,AT1> left_type;
+ typedef cml::vector<E2,AT2> right_type;
+ typedef CML_DEFAULT_BASIS_ORIENTATION basis_orient;
+
+ /* Get matrix size: */
+ enum {
+ array_rows = left_type::array_size,
+ array_cols = right_type::array_size
+ };
+
+ /* Deduce the corresponding matrix types for the vectors: */
+ typedef CML_DEFAULT_ARRAY_LAYOUT layout;
+ typedef typename select_if<
+ array_rows == -1, dynamic<>, fixed<array_rows,1>
+ >::result left_storage;
+ typedef cml::matrix<E1,left_storage,basis_orient,layout> left_matrix;
+
+ typedef typename select_if<
+ array_cols == -1, dynamic<>, fixed<1,array_cols>
+ >::result right_storage;
+ typedef cml::matrix<E2,right_storage,basis_orient,layout> right_matrix;
+
+ /* Finally, promote the matrix types to get the result: */
+ typedef typename et::MatrixPromote<left_matrix,right_matrix>::type type;
+ typedef typename type::temporary_type temporary_type;
+};
+
+} // namespace et
+} // namespace cml
+
+#endif
+
+// -------------------------------------------------------------------------
+// vim:ft=cpp