//
// SPDX-License-Identifier: BSD-3-Clause
// Copyright Contributors to the OpenEXR Project.
//
//
// Algorithms applied to or in conjunction with points (Imath::Vec2
// and Imath::Vec3).
//
// The assumption made is that these functions are called much
// less often than the basic point functions or these functions
// require more support classes.
//
#ifndef INCLUDED_IMATHVECALGO_H
#define INCLUDED_IMATHVECALGO_H
#include "ImathNamespace.h"
#include "ImathVec.h"
IMATH_INTERNAL_NAMESPACE_HEADER_ENTER
/// @cond Doxygen_Suppress
//
// Note: doxygen doesn't understand these templates, so omit these
// functions from the docs.
//
/// Find the projection of vector `t` onto vector `s` (`Vec2`, `Vec3`, `Vec4`)
///
/// Only defined for floating-point types, e.g. `V2f`, `V3d`, etc.
template <class Vec,
IMATH_ENABLE_IF(!std::is_integral<typename Vec::BaseType>::value)>
IMATH_CONSTEXPR14 inline Vec
project (const Vec& s, const Vec& t) IMATH_NOEXCEPT
{
Vec sNormalized = s.normalized();
return sNormalized * (sNormalized ^ t);
}
/// Find a vector that is perpendicular to `s` and
/// in the same plane as `s` and `t` (`Vec2`, `Vec3`, `Vec4`)
///
/// Only defined for floating-point types, e.g. `V2f`, `V3d`, etc.
template <class Vec,
IMATH_ENABLE_IF(!std::is_integral<typename Vec::BaseType>::value)>
constexpr inline Vec
orthogonal (const Vec& s, const Vec& t) IMATH_NOEXCEPT
{
return t - project (s, t);
}
/// Find the direction of a ray `s` after reflection
/// off a plane with normal `t` (`Vec2`, `Vec3`, `Vec4`)
///
/// Only defined for floating-point types, e.g. `V2f`, `V3d`, etc.
template <class Vec,
IMATH_ENABLE_IF(!std::is_integral<typename Vec::BaseType>::value)>
constexpr inline Vec
reflect (const Vec& s, const Vec& t) IMATH_NOEXCEPT
{
return s - typename Vec::BaseType (2) * (s - project (t, s));
}
/// @endcond
/// Find the vertex of triangle `(v0, v1, v2)` that is closest to point `p`
/// (`Vec2`, `Vec3`, `Vec4`)
template <class Vec>
IMATH_CONSTEXPR14 Vec
closestVertex (const Vec& v0, const Vec& v1, const Vec& v2, const Vec& p) IMATH_NOEXCEPT
{
Vec nearest = v0;
typename Vec::BaseType neardot = (v0 - p).length2();
typename Vec::BaseType tmp = (v1 - p).length2();
if (tmp < neardot)
{
neardot = tmp;
nearest = v1;
}
tmp = (v2 - p).length2();
if (tmp < neardot)
{
neardot = tmp;
nearest = v2;
}
return nearest;
}
IMATH_INTERNAL_NAMESPACE_HEADER_EXIT
#endif // INCLUDED_IMATHVECALGO_H
Mini Shell