glm::dmat4 i_mat((*i)->CollisionTransform());
for (auto j = (i + 1); j != end; ++j) {
glm::dvec3 diff((*i)->GetSituation().Position() - (*j)->GetSituation().Position());
double max_dist = ((*i)->Size() + (*j)->Size()) * 1.74;
if (glm::length2(diff) > max_dist * max_dist) continue;
glm::dmat4 i_mat((*i)->CollisionTransform());
for (auto j = (i + 1); j != end; ++j) {
glm::dvec3 diff((*i)->GetSituation().Position() - (*j)->GetSituation().Position());
double max_dist = ((*i)->Size() + (*j)->Size()) * 1.74;
if (glm::length2(diff) > max_dist * max_dist) continue;