This function was added in SA-MP 0.3c and will not work in earlier versions!
(objectid, vehicleid, Float:OffsetX, Float:OffsetY, Float:OffsetZ, Float:RotX, Float:RotY, Float:RotZ)
objectid
The ID of the object to attach to the vehicle. Note that this is an object ID, not a model ID. The object must be CreateObject created first.
vehicleid
The ID of the vehicle to attach the object to.
Float:OffsetX
The X axis offset from the vehicle to attach the object to.
Float:OffsetY
The Y axis offset from the vehicle to attach the object to.
Float:OffsetZ
The Z axis offset from the vehicle to attach the object to.
Float:RotX
The X rotation offset for the object.
Float:RotY
The Y rotation offset for the object.
Float:RotZ
The Z rotation offset for the object.
Note: The object must be created first.
Important Note: When the vehicle is destroyed or respawned, the attached objects won't be destroyed with it; they will remain stationary at the position the vehicle disappeared and be reattached to the next vehicle to claim the vehicle ID that the objects were attached to.
new objectid = CreateObject(...);
new vehicleid = GetPlayerVehicleID(playerid);
AttachObjectToVehicle(objectid, vehicleid, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0);