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quaternion: use consistent order for naive impl

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This commit is contained in:
Danny Robson 2016-10-17 18:58:45 +11:00
parent df27f5f89e
commit b5b7ae3a9a
1 changed files with 6 additions and 6 deletions
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12
quaternion.cpp
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@ -184,14 +184,14 @@ util::rotate (vector3<T> v, quaternion<4,T> q)
{ {
CHECK (is_normalised (v)); CHECK (is_normalised (v));
#if 1 #if 0
util::vector3<T> u { q.x, q.y, q.z }; // Naive:
return v + 2 * cross (u, cross (u, v) + q.w * v); quaternion<4,T> p { 0, v.x, v.y, v.z };
#else
// Verbosely:
quaternionf p { 0, v.x, v.y, v.z };
auto p_ = q * p * conjugate (q); auto p_ = q * p * conjugate (q);
return { p_.x, p_.y, p_.z }; return { p_.x, p_.y, p_.z };
#else
util::vector3<T> u { q.x, q.y, q.z };
return v + 2 * cross (u, cross (u, v) + q.w * v);
#endif #endif
} }