Added typedefs and forward declaration for Math::Frustum.

src/Magnum/Magnum.h

@@ -353,6 +353,9 @@ typedef Math::Range2D<Int> Range2Di;
 /** @brief Signed integer 3D range */
 typedef Math::Range3D<Int> Range3Di;
 
+/** @brief Float frustum */
+typedef Math::Frustum<Float> Frustum;
+
 /*@}*/
 
 /** @{ @name Double-precision types
@@ -465,6 +468,9 @@ typedef Math::Range2D<Double> Range2Dd;
 /** @brief Double 3D range */
 typedef Math::Range3D<Double> Range3Dd;
 
+/** @brief Double frustum */
+typedef Math::Frustum<Double> Frustumd;
+
 /*@}*/
 
 #ifdef MAGNUM_BUILD_DEPRECATED

src/Magnum/Math/Frustum.h

@@ -44,6 +44,7 @@ namespace Magnum { namespace Math {
 
 Stores camera frustum planes in order left (index `0`), right (index `1`),
 bottom (index `2`), top (index `3`), near (index `4`) and far (index `5`).
+@see @ref Magnum::Frustum, @ref Magnum::Frustumd
 */
 template<class T> class Frustum {
     public:

src/Magnum/Math/Math.h

@@ -54,6 +54,8 @@ template<class> class Dual;
 template<class> class DualComplex;
 template<class> class DualQuaternion;
 
+template<class> class Frustum;
+
 template<std::size_t, class> class Matrix;
 template<class T> using Matrix2x2 = Matrix<2, T>;
 template<class T> using Matrix3x3 = Matrix<3, T>;