Thing_Projectile

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134:Thing_Projectile (tid, type, angle, speed, vspeed)

Spawns a projectile. Note that this special requires the actor being spawned to have a SpawnID. To spawn an actor without one, use the SpawnProjectile function instead.

tid: Thing ID of the map spot to spawn the projectile at 
type: Type of projectile to spawn, from the list of Spawn numbers.
angle: Byte angle of the projectile 
speed: Horizontal speed of the projectile in units per tic * 8
vspeed: Vertical speed of the projectile in units per tic * 8 (up is positive)