tgt - target entity (can be either a point or a model entity; if it is
the latter, its midpoint is used)
ht - jump height, measured from the higher one of org and tgt's midpoint
+ pushed_entity - object that is to be pushed
Returns: velocity for the jump
*/
-vector trigger_push_calculatevelocity(vector org, entity tgt, float ht);
+vector trigger_push_calculatevelocity(vector org, entity tgt, float ht, entity pushed_entity);
void trigger_push_touch(entity this, entity toucher);