Reorganized the functions and added comments.

master
Abhinav Sarkar 2013-10-12 16:12:47 +05:30
parent 5a0079eafd
commit 51832ec215
1 changed files with 93 additions and 61 deletions

View File

@ -1,5 +1,5 @@
(ns frpong.core
(:require [frpong.helpers :as h :refer (mult tap)]
(:require [frpong.helpers :refer (mult tap diff-chan key-chan frame-chan sustain)]
[cljs.core.async :refer [<! >! chan put! close! sliding-buffer]]
[domina :as dom :refer [log]])
(:require-macros [cljs.core.async.macros :as m :refer [go]]
@ -55,11 +55,82 @@
paddle-step 20
max-paddle-y (- height paddle-size)
ef-paddle-width (+ paddle-width padding)
init-paddle-pos (/ (- height paddle-size) 2)
[frames stop-frames] (h/frame-chan)]
[frames stop-frames] (frame-chan)]
(defn ticker [frames game-state ticks]
(let [ticks-in (tick-chan (h/diff-chan frames))]
(defn start-game
"Sets up the game, creates the signals and sets up the components, and starts the game."
[]
(let [pos (chan 1) ;; ball position signal
vel (chan 1) ;; ball velocity signal
pl-pos (chan 1) ;; paddle left position signal
pr-pos (chan 1) ;; paddle right position signal
game-state (chan 1)] ;; game state signal
(layout-game)
(setup-components frames game-state pos vel pl-pos pr-pos)
;; start the game by setting the initial values of the signals
(put! pos init-pos)
(put! vel init-vel)
(put! pl-pos init-paddle-pos)
(put! pr-pos init-paddle-pos)
(put! game-state :moving)))
(defn layout-game
"Lays out the game screen."
[]
(doto (dom/by-id "canvas")
(dom/set-style! "width" (str width "px"))
(dom/set-style! "height" (str height "px")))
(doto (dom/by-id "ball")
(dom/set-attr! "r" ball-radius)
(dom/set-attr! "cx" (first init-pos))
(dom/set-attr! "cy" (second init-pos)))
(doseq [id ["lpaddle" "rpaddle"]]
(doto (dom/by-id id)
(dom/set-attr! "width" paddle-width)
(dom/set-attr! "height" paddle-size)
(dom/set-attr! "y" (/ (- height paddle-size) 2))))
(dom/set-attr! (dom/by-id "lpaddle") "x" 0)
(dom/set-attr! (dom/by-id "rpaddle") "x" (- width paddle-width)))
(defn setup-components
"Multiplexes the signals and sets up the components by connecting them using the signals
tapped from the multiplexers.
The signals are taken as parameters."
[frames game-state pos vel pl-pos pr-pos]
(let [ticks (chan) ;; tick signal
ticks-m (mult ticks) ;; mutliplexers for all signals
pos-m (mult pos)
vel-m (mult vel)
pl-pos-m (mult pl-pos)
pr-pos-m (mult pr-pos)
game-state-m (mult game-state)
;; paddle position signals are not at the same rate as the rest so they need to be
;; sustained at the ticks rate
pl-pos-sust (sustain (tap pl-pos-m) (tap ticks-m (chan (sliding-buffer 1000))))
pr-pos-sust (sustain (tap pr-pos-m) (tap ticks-m (chan (sliding-buffer 1000))))]
;; set up the components
(ticker frames (tap game-state-m) ticks)
(ball-positioner (tap ticks-m) (tap vel-m) (tap pos-m) pos)
(paddle-positioner {83 :down 87 :up} (tap pl-pos-m) pl-pos)
(paddle-positioner {38 :up 40 :down} (tap pr-pos-m) pr-pos)
(collision-detector (tap ticks-m) (tap pos-m) (tap vel-m)
pl-pos-sust pr-pos-sust game-state vel)
(renderer (tap ticks-m) (tap game-state-m) (tap pos-m) (tap pl-pos-m) (tap pr-pos-m))))
(defn ticker
"Ticker component.
Converts `frames` signal to ticks and outputs them to the `ticks` signal
as long as the `game-state` signal is not :gameover. Once the `game-state` signal is
:gameover, stops the `frames` signal hence stopping the entire game."
[frames game-state ticks]
(let [ticks-in (tick-chan (diff-chan frames))]
(go (loop []
(let [gs (<! game-state)]
(do (>! ticks (<! ticks-in))
@ -67,14 +138,18 @@
(stop-frames)
(recur))))))))
(defn ball-positioner [ticks vel pos-in pos-out]
(defn ball-positioner
"Ball Positioner component.
Calculates the next ball position using the current ball position (from the `pos-in` signal)
and the current tick (from the `ticks` signal) and outputs it to the `pos-out` signal."
[ticks vel pos-in pos-out]
(go-loop
(let [tick (<! ticks)
pos-next (next-pos (<! pos-in) (<! vel) tick)]
(>! pos-out pos-next))))
(defn paddle-positioner [keycodes pos-in pos-out]
(let [keys (h/key-chan keycodes)]
(let [keys (key-chan keycodes)]
(go-loop
(let [pos (<! pos-in)]
(>! pos-out
@ -83,6 +158,12 @@
:down (min (+ pos paddle-step) max-paddle-y)))))))
(defn collision-detector [ticks pos vel-in pl-pos pr-pos game-state vel-out]
"Collision Detector component.
Detects the collision of the ball with the walls and the paddles and accordingly calculates
and outputs the next ball velocity and next game state to the `vel-out` and `game-state`
signals respectively.
Reads the current tick, ball position, ball velocity and left and right paddle positions from
the `ticks`, `pos`, `vel-in`, `pl-pos` and `pr-pos` signals respectively."
(defn in-y-range? [y paddle-y]
(and (> y (+ paddle-y padding)) (< y (- (+ paddle-y paddle-size) padding))))
@ -129,7 +210,11 @@
(collision? x-state y-state) :collision
:else :moving)))))
(defn renderer [ticks game-state pos pl-pos pr-pos]
(defn renderer
"Renderer component.
Renders the ball and paddle positions on the browser. Also shows the game state and stats.
Reads the current values from the signals supplied as parameters."
[ticks game-state pos pl-pos pr-pos]
(let [ball-el (dom/by-id "ball")
state-el (dom/by-id "state")
lpaddle-el (dom/by-id "lpaddle")
@ -149,58 +234,5 @@
(go-loop
(dom/set-attr! rpaddle-el "y" (<! pr-pos)))))
(defn setup-components [frames game-state pos vel pl-pos pr-pos]
(let [ticks (chan)
ticks-m (mult ticks)
pos-m (mult pos)
vel-m (mult vel)
pl-pos-m (mult pl-pos)
pr-pos-m (mult pr-pos)
game-state-m (mult game-state)]
(ticker frames (tap game-state-m) ticks)
(ball-positioner (tap ticks-m) (tap vel-m) (tap pos-m) pos)
(paddle-positioner {83 :down 87 :up} (tap pl-pos-m) pl-pos)
(paddle-positioner {38 :up 40 :down} (tap pr-pos-m) pr-pos)
(collision-detector (tap ticks-m) (tap pos-m) (tap vel-m)
(h/sustain (tap pl-pos-m) (tap ticks-m (chan (sliding-buffer 1000))))
(h/sustain (tap pr-pos-m) (tap ticks-m (chan (sliding-buffer 1000))))
game-state vel)
(renderer (tap ticks-m) (tap game-state-m) (tap pos-m) (tap pl-pos-m) (tap pr-pos-m))))
(defn layout-game []
(doto (dom/by-id "canvas")
(dom/set-style! "width" (str width "px"))
(dom/set-style! "height" (str height "px")))
(doto (dom/by-id "ball")
(dom/set-attr! "r" ball-radius)
(dom/set-attr! "cx" (first init-pos))
(dom/set-attr! "cy" (second init-pos)))
(doseq [id ["lpaddle" "rpaddle"]]
(doto (dom/by-id id)
(dom/set-attr! "width" paddle-width)
(dom/set-attr! "height" paddle-size)
(dom/set-attr! "y" (/ (- height paddle-size) 2))))
(dom/set-attr! (dom/by-id "lpaddle") "x" 0)
(dom/set-attr! (dom/by-id "rpaddle") "x" (- width paddle-width)))
(defn start-game []
(let [init-paddle-pos (/ (- height paddle-size) 2) ;; initial paddle position
pos (chan 1) ;; ball position signal
vel (chan 1) ;; ball velocity signal
pl-pos (chan 1) ;; paddle left position signal
pr-pos (chan 1) ;; paddle right position signal
game-state (chan 1)] ;; game state signal
(layout-game)
(setup-components frames game-state pos vel pl-pos pr-pos)
;; start the game by setting the initial values of the signals
(put! pos init-pos)
(put! vel init-vel)
(put! pl-pos init-paddle-pos)
(put! pr-pos init-paddle-pos)
(put! game-state :moving)))
;; Everything is ready now. Start the game!
(start-game)))