Any way to detect if object is near another object?
You can check the distance from one node to another, but if you want to do it often (each frame) and/or on many objects then put a collision sphere on each object and let the collision detection system do that for you.
I guess one lightweight way to do that is to compare the squared distance.
radius = 2.0 radiusSq = radius * radius isNear = (obj.getPos() - target.getPos()).lengthSquared() <= radiusSq
Or even, if you do not want to take the Z into account:
radius = 2.0 radiusSq = radius * radius isNear = (obj.getXy() - target.getXy()).lengthSquared() <= radiusSq