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bz_getPlayerVelocity
bool bz_getPlayerVelocity (int playerID, float vel [3])
Minimum API Version: 2.99.x or later 
Fills the float array "vel" with the current velocity of the player.
Parameters: 
playerID  -  Player to lookup. 
vel [3]  -  Velocity (x, y, z) 
Returns: 
Whether the player exists.