glm/glm/gtx/vector_angle.inl
John McFarlane 506a487d24 parameterize number of dimensions of vector in tvec<D, T, P>
- specializes for 1, 2, 3 and 4-dimensional vector types
  which are then aliased as tvec1, tvec2, tvec3 and tvec4
- requires C++11 aliases; breaks compatability with C++03
- tested on:
  - clang-3.5.2, clang-3.8.0
  - gcc 4.8.5, gcc 5.4.1, gcc 6.2.0

TODO:
- still uses template template parameters - most can probably be removed
- some definitions might now be de-duplicated
2016-12-28 17:07:12 -08:00

59 lines
1.5 KiB
C++

/// @ref gtx_vector_angle
/// @file glm/gtx/vector_angle.inl
namespace glm
{
template <typename genType>
GLM_FUNC_QUALIFIER genType angle
(
genType const & x,
genType const & y
)
{
GLM_STATIC_ASSERT(std::numeric_limits<genType>::is_iec559, "'angle' only accept floating-point inputs");
return acos(clamp(dot(x, y), genType(-1), genType(1)));
}
template <int D, typename T, precision P, template <int, typename, precision> class vecType>
GLM_FUNC_QUALIFIER T angle
(
vecType<D, T, P> const & x,
vecType<D, T, P> const & y
)
{
GLM_STATIC_ASSERT(std::numeric_limits<T>::is_iec559, "'angle' only accept floating-point inputs");
return acos(clamp(dot(x, y), T(-1), T(1)));
}
//! \todo epsilon is hard coded to 0.01
template <typename T, precision P>
GLM_FUNC_QUALIFIER T orientedAngle
(
tvec2<T, P> const & x,
tvec2<T, P> const & y
)
{
GLM_STATIC_ASSERT(std::numeric_limits<T>::is_iec559, "'orientedAngle' only accept floating-point inputs");
T const Angle(acos(clamp(dot(x, y), T(-1), T(1))));
if(all(epsilonEqual(y, glm::rotate(x, Angle), T(0.0001))))
return Angle;
else
return -Angle;
}
template <typename T, precision P>
GLM_FUNC_QUALIFIER T orientedAngle
(
tvec3<T, P> const & x,
tvec3<T, P> const & y,
tvec3<T, P> const & ref
)
{
GLM_STATIC_ASSERT(std::numeric_limits<T>::is_iec559, "'orientedAngle' only accept floating-point inputs");
T const Angle(acos(clamp(dot(x, y), T(-1), T(1))));
return mix(Angle, -Angle, dot(ref, cross(x, y)) < T(0));
}
}//namespace glm