///////////////////////////////////////////////////////////////////////////////////
/// OpenGL Mathematics (glm.g-truc.net)
///
/// Copyright (c) 2005 - 2012 G-Truc Creation (www.g-truc.net)
/// Permission is hereby granted, free of charge, to any person obtaining a copy
/// of this software and associated documentation files (the "Software"), to deal
/// in the Software without restriction, including without limitation the rights
/// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
/// copies of the Software, and to permit persons to whom the Software is
/// furnished to do so, subject to the following conditions:
///
/// The above copyright notice and this permission notice shall be included in
/// all copies or substantial portions of the Software.
///
/// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
/// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
/// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
/// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
/// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
/// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
/// THE SOFTWARE.
///
/// @ref core
/// @file glm/core/func_geometric.hpp
/// @date 2008-08-03 / 2011-06-14
/// @author Christophe Riccio
///
/// @see <a href="http://www.opengl.org/registry/doc/GLSLangSpec.4.20.8.pdf">GLSL 4.20.8 specification, section 8.5 Geometric Functions</a>
///
/// @defgroup core_func_geometric Geometric functions
/// @ingroup core
///
/// These operate on vectors as vectors, not component-wise.
///////////////////////////////////////////////////////////////////////////////////

#ifndef glm_core_func_geometric
#define glm_core_func_geometric GLM_VERSION

namespace glm {
/// @addtogroup core_func_geometric
/// @{

/// Returns the length of x, i.e., sqrt(x * x).
///
/// @tparam genType Floating-point vector types.
///
/// @see <a href="http://www.opengl.org/sdk/docs/manglsl/xhtml/length.xml">GLSL length man page</a>
/// @see <a href="http://www.opengl.org/registry/doc/GLSLangSpec.4.20.8.pdf">GLSL 4.20.8 specification, section 8.5 Geometric Functions</a>
template<typename genType>
typename genType::value_type length(
  genType const & x);

/// Returns the distance betwwen p0 and p1, i.e., length(p0 - p1).
///
/// @tparam genType Floating-point vector types.
///
/// @see <a href="http://www.opengl.org/sdk/docs/manglsl/xhtml/distance.xml">GLSL distance man page</a>
/// @see <a href="http://www.opengl.org/registry/doc/GLSLangSpec.4.20.8.pdf">GLSL 4.20.8 specification, section 8.5 Geometric Functions</a>
template<typename genType>
typename genType::value_type distance(
  genType const & p0,
  genType const & p1);

/// Returns the dot product of x and y, i.e., result = x * y.
///
/// @tparam genType Floating-point vector types.
///
/// @see <a href="http://www.opengl.org/sdk/docs/manglsl/xhtml/dot.xml">GLSL dot man page</a>
/// @see <a href="http://www.opengl.org/registry/doc/GLSLangSpec.4.20.8.pdf">GLSL 4.20.8 specification, section 8.5 Geometric Functions</a>
template<typename genType>
typename genType::value_type dot(
  genType const & x,
  genType const & y);

/// Returns the cross product of x and y.
///
/// @tparam valType Floating-point scalar types.
///
/// @see <a href="http://www.opengl.org/sdk/docs/manglsl/xhtml/cross.xml">GLSL cross man page</a>
/// @see <a href="http://www.opengl.org/registry/doc/GLSLangSpec.4.20.8.pdf">GLSL 4.20.8 specification, section 8.5 Geometric Functions</a>
template<typename valType>
detail::tvec3<valType> cross(
  detail::tvec3<valType> const & x,
  detail::tvec3<valType> const & y);

/// Returns a vector in the same direction as x but with length of 1.
///
/// @see <a href="http://www.opengl.org/sdk/docs/manglsl/xhtml/normalize.xml">GLSL normalize man page</a>
/// @see <a href="http://www.opengl.org/registry/doc/GLSLangSpec.4.20.8.pdf">GLSL 4.20.8 specification, section 8.5 Geometric Functions</a>
template<typename genType>
genType normalize(
  genType const & x);

/// If dot(Nref, I) < 0.0, return N, otherwise, return -N.
///
/// @tparam genType Floating-point vector types.
///
/// @see <a href="http://www.opengl.org/sdk/docs/manglsl/xhtml/faceforward.xml">GLSL faceforward man page</a>
/// @see <a href="http://www.opengl.org/registry/doc/GLSLangSpec.4.20.8.pdf">GLSL 4.20.8 specification, section 8.5 Geometric Functions</a>
template<typename genType>
genType faceforward(
  genType const & N,
  genType const & I,
  genType const & Nref);

/// For the incident vector I and surface orientation N,
/// returns the reflection direction : result = I - 2.0 * dot(N, I) * N.
///
/// @tparam genType Floating-point vector types.
///
/// @see <a href="http://www.opengl.org/sdk/docs/manglsl/xhtml/reflect.xml">GLSL reflect man page</a>
/// @see <a href="http://www.opengl.org/registry/doc/GLSLangSpec.4.20.8.pdf">GLSL 4.20.8 specification, section 8.5 Geometric Functions</a>
template<typename genType>
genType reflect(
  genType const & I,
  genType const & N);

/// For the incident vector I and surface normal N,
/// and the ratio of indices of refraction eta,
/// return the refraction vector.
///
/// @tparam genType Floating-point vector types.
///
/// @see <a href="http://www.opengl.org/sdk/docs/manglsl/xhtml/refract.xml">GLSL refract man page</a>
/// @see <a href="http://www.opengl.org/registry/doc/GLSLangSpec.4.20.8.pdf">GLSL 4.20.8 specification, section 8.5 Geometric Functions</a>
template<typename genType>
genType refract(
  genType const & I,
  genType const & N,
  typename genType::value_type const & eta);

/// @}
} //namespace glm

#include "func_geometric.inl"

#endif //glm_core_func_geometric
