Called to determine if a player should be able to pick up an entity with the Physics Gun. See GM:OnPhysgunPickup for a hook which is called when a player has successfully picked up an entity. See GM:GravGunPickupAllowed for the Gravity Gun pickup variant. See GM:AllowPlayerPickup for the +USE...
Sets the entity's move type. This should be called before initializing the physics object on the entity, unless it will override SetMoveType such as Entity:PhysicsInitBox. Despite existing on client, it doesn't actually do anything on client.
Gets all entities within the specified sphere. This internally uses a Spatial Partition to avoid looping through all entities. Clientside entities will not be returned by this function. This function internally calls ents. FindInBox with some radius checks.
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если начнёшь писать свой, с этими материалами станет проще