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matrix: fix transposed matrix in look_at

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This commit is contained in:
Danny Robson 2016-10-17 16:51:26 +11:00
parent 9cff1e9c85
commit 607aaceb29
1 changed files with 18 additions and 12 deletions
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30
matrix.cpp
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@ -282,26 +282,32 @@ matrix<S,T>::perspective (T fov, T aspect, range<T> Z)
//----------------------------------------------------------------------------- //-----------------------------------------------------------------------------
// Emulates gluLookAt // Emulates gluLookAt
//
// Translates the viewpoint to the origin, then rotates the world to point
// along eye to centre (negative-Z).
// Implemented for right handed world coordinates.
//
// Assumes 'up' is normalised.
template <size_t S, typename T> template <size_t S, typename T>
matrix4<T> matrix4<T>
matrix<S,T>::look_at (util::point<3,T> eye, matrix<S,T>::look_at (const util::point<3,T> eye,
util::point<3,T> target, const util::point<3,T> centre,
util::vector<3,T> up) const util::vector<3,T> up)
{ {
CHECK (is_normalised (up)); CHECK (is_normalised (up));
auto forward = normalised (eye.to (target)); const auto f = normalised (centre - eye);
auto side = normalised (cross (forward, up)); const auto s = normalised (cross (f, up));
up = cross (side, forward); const auto u = cross (s, f);
auto rot = util::matrix4<T> {{ const util::matrix4<T> rot {{
{ side[0], up[0], -forward[0], 0 }, { s.x, s.y, s.z, 0 },
{ side[1], up[1], -forward[1], 0 }, { u.x, u.y, u.z, 0 },
{ side[2], up[2], -forward[2], 0 }, {-f.x,-f.y,-f.z, 0 },
{ 0, 0, 0, 1 } { 0, 0, 0, 1 },
}}; }};
return rot * util::matrix4<T>::translation (-eye.template as<vector> ()); return rot * util::matrix4<T>::translation (0-eye);
} }