if the truck moved, false if it arrived
Override, should return true if the object does belong to the given faction
Draws the object
Draws the truck
Override, do anything before saving. Return DESTROY_OBJECT to destroy the object
Returns the world space position of this projectile
Computes the effective speed of the truck in world pixels / logic frame
Returns if the truck has arrived
Returns if the truck can get delivered
Override, should return false if this object is no longer important for the game, e.g. because it now only displays cosmetic effects or so
Tries to merge with the other truck
Advances the truck by the given amount. Amount is world space pixels here