Fast access to information on a Unity GameObject without having to call GetComponent.

FastLookup.cs

using UnityEngine;

public class FastLookup : MonoBehaviour
{
	[SerializeField]
	public static int LookupListSize = 1597;//547; //!< Size of static data arrays. Prime numbers are best, in theory.
	
	public const uint FlagAllocated = 1 << 0; //!< This index has been reserved for use.
	
	public uint Idx; //!< Per-instance index into the static data arrays.
	
	//! Convert an instance id to a FastLookup Index.
	//!
	//! @param instanceId    Unity Object instance id, obtained via Object.GetInstanceID()
	//!
	//! @return A unique index into the FastLookup static data arrays.
	public static uint InstanceIdToIndex(int instanceId)
	{
		return (uint)instanceId % (uint)Flags.Length;
	}
	
#region Data Arrays
	public static uint[] Flags;
	public static Vector3[] LastPosition;
	public static Vector3[] Position;
#endregion
	
#region MonoBehavior Stuff
	void OnEnable()
	{
		if(Flags == null)
		{
			Flags = new uint[LookupListSize];
			LastPosition = new Vector3[LookupListSize];
			Position = new Vector3[LookupListSize];
		}

		Idx = InstanceIdToIndex(gameObject.GetInstanceID());

		// If we're debugging, put in some extra checks
#if UNITY_EDITOR
		if((Flags[Idx] & FlagAllocated) == FlagAllocated)
		{
			Debug.Log("InstanceId collision detected! Consider increasing lookup list size.");
			Debug.Break();
		}
#endif

		Flags[Idx] = FlagAllocated;
	}
	
	void OnDisable() 
	{
		Flags[Idx] = 0;
	}
#endregion
}