UniqueTID

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(New from 2.7.1)

int UniqueTID ([int tid[, int limit]])

Usage

Returns a new TID that is not currently used by any actors.

Parameters

  • tid: Starting value from which to check. It has two modes of operation:
  1. If tid is non-zero, then it checks TIDs one-by-one starting at the given tid until it finds a free one.
  2. If tid is zero, then it returns a completely random TID.
  • limit: Specifies the number of attempts to make to find a free TID. If limit is non-zero, then it will only check that many times for a free TID, so it might not find a free one. If no free TID is found, 0 is returned. If limit is zero, then the search is effectively unlimited.

Return value

0 if no free TID is found, a positive value corresponding to an unused TID otherwise.

Examples

This example is part of the code that can be used to see through the "eyes" of a missile(akin to Unreal Tournament's Redeemer) It is called in the Spawn state of the missile.

script "CameraRocket" (void)
{
     int MissileID = UniqueTID(); // Get a random TID, it is sure that it will not use an already used one.
     Thing_ChangeTID(0, MissileID); // Set that TID to the fired missile
     SetActivatorToTarget(MissileID); // Use the target to select the player who fired this missile
     ChangeCamera(MissileID, 0, 0); // Set the camera for the player
     SetPlayerProperty(0, ON, PROP_Frozen); // Don't let the player move
     Thing_ChangeTID(MissileID, 0); // Remove the TID from the missile, as it is no longer needed.
}

Note that the above function does not include turning of the missile based on the view angle or unfreezing the player when it explodes.