Thing_ProjectileIntercept

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175:Thing_ProjectileIntercept(tid, type, speed, target, newtid)

tid: Thing ID of the map spot to spawn the projectile at
type: Type of projectile to spawn
speed: Speed of the projectile in units per tic * 8
target: Thing ID of the thing you want the projectile fired at
newtid: TID you want assigned to the spawned projectile (optional)

Spawns a projectile, much like Thing_ProjectileAimed, but tries to intercept the target. Basically, it tries to predict where its target will be based on the target's current speed and direction. If the target changes speed/direction after the projectile is spawned, chances are the projectile will not hit. The main way I use it is making a hassle for the player. By giving a player a TID (see Thing_ChangeTID), you can use this special to send the fireballs their way.

The higher the projectile's speed, the harder it is to dodge it, since there's less of a window of opportunity to change your speed/direction and get out of its way before it hits home.

Usage:

TID is a number that makes a thing unique, the default is zero, and therefore a TID is usually set to something else, like 1. In Doom Builder you have to right click on a thing, select the Effects tab and change the Thing Tag to something besides 0.

The type is actually from the list of Spawn_numbers. You can either use the number or the defined name (T_SOMETHING) for clarity.

Speed is a number between 0-255.

Target same TID idea as mentioned above.

New TID is just a way to make the spawned thing unique if you need to refer to it later. It is just a number.