namespace glm { template GLM_FUNC_QUALIFIER qua rotate(qua const& q, T const& angle, vec<3, T, Q> const& v) { vec<3, T, Q> Tmp = v; // Axis of rotation must be normalised T len = glm::length(Tmp); if(abs(len - static_cast(1)) > static_cast(0.001)) { T oneOverLen = static_cast(1) / len; Tmp.x *= oneOverLen; Tmp.y *= oneOverLen; Tmp.z *= oneOverLen; } T const AngleRad(angle); T const Sin = sin(AngleRad * static_cast(0.5)); return q * qua(cos(AngleRad * static_cast(0.5)), Tmp.x * Sin, Tmp.y * Sin, Tmp.z * Sin); } }//namespace glm