Bumper Two Player

First, a confession: we don’t actually make the boats bump each other. We needed to finish the discussion in one day, so we did not add any physics that wasn’t present in the one-player version.

One Player Review

The one player code does the following:

• Bounce off walls
• Clicking sets velocity to be toward click at 5 units/tick
• w / s keys make the radius increase / decrease by 5 units.
• j / k keys make the speed decrease / increase by 10%.
• c gives a new random color

Requiring bumper-boats-single.rkt gives the following functions:

• WIDTH, HEIGHT of the screen
• tick-h
• mouse-h
• key-h
• draw-1-fancy: Boat -> Image: Render one boat, ready to place.
• Boat: the boat structure

(define-struct boat ([id : Integer] [name : String]
                     [pos : Posn]  [vel : Posn]
                     [color : Color]
                     [radius : Positive-Integer])

Two Player Conversion

The Game structure was a number to keep track of whose turn it is and two Boat structures, one for each player. Require the one player file so the old functions are available.

(require "bumper-boats.single.rkt")

• Draw-Handler: Place the results from draw-1-fancy of each player’s boat.
• Key-Handler: Determine whose turn it is, and replace that boat with the results of running the one-player key handler on that boat. Update whose turn it is.
• Tick-Handler: Update both boats simultaneously.
• Mouse-Handler: Like the key handler.