extend method
Extend this AABB so that it covers the given AABB too.
Implementation
void extend(AABB aabb) {
lowerBound.x = math.min(lowerBound.x, aabb.lowerBound.x);
upperBound.x = math.max(upperBound.x, aabb.upperBound.x);
lowerBound.y = math.min(lowerBound.y, aabb.lowerBound.y);
upperBound.y = math.max(upperBound.y, aabb.upperBound.y);
lowerBound.z = math.min(lowerBound.z, aabb.lowerBound.z);
upperBound.z = math.max(upperBound.z, aabb.upperBound.z);
}