1.3.2.4 Tactics🔗

The direction change chance is the chance of making a random direction change when a bot is wandering around the world. This is set to a 20% chance.

(define direction-change-chance (make-parameter 0.2))

The choice structure is used to return information about what a strategy has chosen for the next action.

(struct choice (type parameter direction))

When a strategy chooses to move a bot, the choice parameter is the destination.

(test-case:

"choose move"

(let ([choice (choose-move direction-west direction-east

(step #f request-move #f #t (bot #f (location 2 1) #f #f)))])

(check-equal? (choice-type choice) request-move)

(check-equal? (choice-parameter choice) (location 1 1))

(check-equal? (choice-direction choice) direction-west)))

(define (move-failed? step)

(and (equal? (step-request-type step) request-move)

(not (step-success? step))))

(define (choose-move chosen-direction current-direction step)

(let ([direction

(if (move-failed? step)

(change-direction (step-bot step) current-direction)

chosen-direction)])

(choice request-move

(direction (step-location step))

direction)))

When a strategy chooses to take a block, the choice parameter is block id. The next move direction is the direction to the block.

(test-case:

"choose take"

(let ([choice (choose-take

(bot (entity 101 type-bot) (location 1 1) #f #f)

(occupant (entity 102 type-block) (location 1 2)))])

(check-equal? (choice-type choice) request-take)

(check-equal? (choice-parameter choice) 102)

(check-equal? (choice-direction choice) direction-north)))

(define (choose-take bot block)

(let ([take-direction (direction-from (bot-location bot) (occupant-location block))])

(choice request-take (occupant-id block) take-direction)))

When a strategy chooses to transfer a block to a base, the choice parameter is the base id. The next move direction is away from the base.

(test-case:

"choose transfer"

(let* ([base (occupant (entity 102 type-base) (location 1 2))]

[choice (choose-transfer

(bot (entity 101 type-bot) (location 1 1) #f (list base))

base)])

(check-equal? (choice-type choice) request-transfer)

(check-equal? (choice-parameter choice) 102)

(check-equal? (choice-direction choice) direction-south)))

(define (choose-transfer bot base)

(choice request-transfer (occupant-id base)

(direction-from (occupant-location base) (bot-location bot))))