Lisp Game Programming <Step12-3>

ここまでのプログラムをまとめると以下
なんとかgameの形になった

　⇒ step12.lisp

;;;; The Common-Shooter

;;; step1 <Game Frame>
;;; step2 <Audio>
;;; step3 <Sprite Sheets> <Character Object> <Draw> <Initialize>
;;; step4 <Scroll> <Scroll Counter>
;;; step5 <Font> <Score Panel>
;;; step6 <Key State>
;;; step7 <Game Field>
;;; step8 <Shot>
;;; step9 <Move Enemy> <Set Enemy> <Remove Dead Eenemy>
;;; step10 <Move Enemy Shot> <Set Enemy Shot> <Remove Dead Enemy Shot>
;;; step11 <Judge Enemy Shot Hit> <Game Over Message> <Explode Ship> <Revive Ship>
;;; step12 <Judge Shot Hit>

;; step2 <Audio>
;; -----------------------------------------------------------------------------------------------
(defparameter *path-shot-sound* "C:\\work\\sound\\tm2_shoot003.wav")
(defparameter *path-shipbom-sound* "C:\\work\\sound\\bom01.wav")
(defparameter *path-enemybom-sound* "C:\\work\\sound\\tm2_bom001.wav")
(defparameter *path-background-music* "C:\\work\\sound\\rbutai_xg.mid")
(defvar *shot-sound*) ; shot sound
(defvar *shipbom-sound*) ; ship bom sound
(defvar *enemybom-sound*) ; enemy bom sound
(defvar *bg-music*) ; background music

(defun Open-sound ()
  "load sound data and set"
(sdl-mixer:open-audio :chunksize 1024 :channels 2)
(sdl-mixer:allocate-channels 16)
(setf *shot-sound* (sdl-mixer:load-sample *path-shot-sound*)
          *shipbom-sound* (sdl-mixer:load-sample *path-shipbom-sound*)
          *enemybom-sound* (sdl-mixer:load-sample *path-enemybom-sound*)
          *bg-music* (sdl-mixer:load-music *path-background-music*)))

(defun Stop-sound ()
  "sound stop"
(when (sdl-mixer:music-playing-p)
    (sdl-mixer:halt-music)) ; BGM stop
(when (sdl-mixer:sample-playing-p nil)
    (sdl-mixer:halt-sample))) ; Shot,Bom sound stop

(defun Close-sound ()
"close sound file"
(sdl-mixer:free *shot-sound*) ; free shot sound
(sdl-mixer:free *shipbom-sound*) ; freeship bom sound
(sdl-mixer:free *enemybom-sound*) ; free enemy bom s ound
(sdl-mixer:free *bg-music*) ; free background music
(sdl-mixer:close-audio))

(defun Play-music (music)
"play music"
(sdl-mixer:play-music music :loop t :position 0)) ; BGM start

(defun Play-sample (sample)
"play sample"
(sdl-mixer:play-sample sample)) ; shot sound

;; step3 <Sprite sheets>
;; -----------------------------------------------------------------------------------------------
(defparameter *path-size32* "C:\\work\\graphics\\size32.bmp") ; set path to size32.bmp
(defparameter *path-size64* "C:\\work\\graphics\\size64.bmp") ; set path to size64.bmp
(defparameter *path-size16* "C:\\work\\graphics\\size16.bmp") ; set path to size16.bmp
(defvar *image0*)
(defvar *image1*)
(defvar *image2*)

(defun Set-imageid ()
"load imagedata and set id"
(setf *image0* (sdl:load-image *path-size32* :color-key(sdl:color :r 0 :g 0 :b 0))
          *image1* (sdl:load-image *path-size64* :color-key(sdl:color :r 0 :g 0 :b 0))
          *image2* (sdl:load-image *path-size16* :color-key(sdl:color :r 0 :g 0 :b 0)))
(let ((temp0 (append (loop for x from 0 to 128 by 32 ; id 0-4 ship,shot,enemy1,enemy2,enemy3
                                     collect (list x 0 32 32))))
         (temp1 (append (loop for x from 0 to 128 by 64 ; id 0-2 mapchip,enemy-explosion,my-explosion
                                     collect (list x 0 64 64))))
         (temp2 (append (loop for x from 0 to 16 by 16 ; id 0-1 pointer,enemy-shot
                                     collect (list x 0 16 16)))))
(setf (sdl:cells *image0*) temp0
(sdl:cells *image1*) temp1
(sdl:cells *image2*) temp2)))

;;step3 <Character object>
;; -----------------------------------------------------------------------------------------------
(defclass object ()
((%imageid :initarg :imageid :initform 0 :accessor imageid) ; 3 imageid available
   (%id :initarg :id :initform 0 :accessor id) ; graphic id in imageid
   (%x :initarg :x :initform 0 :accessor x) ; x (upper left corner)
   (%y :initarg :y :initform 0 :accessor y) ; y (upper left corner)
   (%width :initarg :width :initform 0 :accessor width) ; x (upper left corner)
   (%height :initarg :height :initform 0 :accessor height)) ; y (upper left corner)
(:documentation "The Object Class"))

(defclass entity (object)
((%dx :initarg :dx :initform 0 :accessor dx) ; x direction speed
   (%dy :initarg :dy :initform 0 :accessor dy) ; y direction speed
   (%move-cnt :initarg :move-cnt :initform 0 :accessor move-cnt) ; moving counter(distance)
   (%revival-cnt :initarg :revival-cnt :initform 0 :accessor revival-cnt) ; revival counter(wait)
   (%explode-cnt :initarg :explode-cnt :initform 0 :accessor explode-cnt) ; explosion counter(wait)
   (%state :initarg :state :initform 0 :accessor state)) ; 0:dead 1:alive 2:explosion 3:revival
(:documentation "The Entity Class"))

;; step3 <Draw images>
;; -----------------------------------------------------------------------------------------------
(defun Draw (obj)
  "character draw"
(ecase (imageid obj)
    (0 (sdl:draw-surface-at-* *image0* (x obj) (y obj) :cell (id obj)))
    (1 (sdl:draw-surface-at-* *image1* (x obj) (y obj) :cell (id obj)))
    (2 (sdl:draw-surface-at-* *image2* (x obj) (y obj) :cell (id obj)))))

;; step3 <Initialize>
;; -----------------------------------------------------------------------------------------------
(defun Initialize ()
"graphics initialize"
(setf (sdl:frame-rate) 60) ; frame rate set
(setf *random-state* (make-random-state t)) ; random set
(Set-imageid) ; imageid set
(sdl:show-cursor nil)) ; cursor not show

;; step 4 <Scroll>
;; -----------------------------------------------------------------------------------------------
(defclass timing ()
((%scroll :initarg :scroll :initform 0 :accessor scroll) ; scroll counter
(%interval :initarg :interval :initform 128 :accessor interval)) ; step 9 add sentence
(:documentation "The timing Class"))

(defgeneric Scroll-background (mapchip timing))

(defmethod Scroll-background (mapchip timing)
  "draw background"
(setf (y mapchip) (+ -64 (mod (scroll timing) 64))) ; scroll start from y(-64) to y(0)
(dotimes (i 9)
    (setf (x mapchip) 0)
      (dotimes (j 8)
        (Draw mapchip)
        (incf (x mapchip) 64))
      (incf (y mapchip) 64)))

;; step5 <Font>
;; -----------------------------------------------------------------------------------------------
(defparameter *path-font72* "C:\\WINDOWS\\Fonts\\times.ttf")
(defparameter *path-font16* "C:\\WINDOWS\\Fonts\\msmincho.ttc")
(defparameter *font72* (make-instance 'sdl:ttf-font-definition
                                                              :size 72
                                                              :filename (sdl:create-path *path-font72*)))
(defparameter *font16* (make-instance 'sdl:ttf-font-definition
                                                              :size 16
                                                              :filename (sdl:create-path *path-font16*)))
(defvar *title-font*) ; title font
(defvar *menu-font*) ; menu font

(defun Set-font ()
(setf *title-font* (sdl:initialise-font *font72*)
*menu-font* (sdl:initialise-font *font16*)))

;; step5 <Score panel>
;; -----------------------------------------------------------------------------------------------
(defclass score ()
((%score :initarg :score :initform 0 :accessor score) ; score counter
   (%highscore :initarg :highscore :initform 5000 :accessor highscore) ; highscore
   (%n-ship :initarg :n-ship :initform 3 :accessor n-ship)) ; number of ship
(:documentation "The Score Class"))

(defgeneric Score-panel (score score-ship))

(defmethod Score-panel (score score-ship) ; score panel message
  "draw score and ships of rest"
(sdl:draw-box-* 480 0 160 480 :color (sdl:color :r 64 :g 64 :b 64))
(sdl:draw-string-solid-* (format nil "SCORE:") 496 32 :color sdl:*white* :font *menu-font*)
(sdl:draw-string-solid-* (format nil "HIGH-SCORE:") 496 72 :color sdl:*white* :font *menu-font*)
(sdl:draw-string-solid-* (format nil "~7,'0d" (score score)) 512 52 :color sdl:*white* :font *menu-font*)
(sdl:draw-string-solid-* (format nil "~7,'0d" (highscore score)) 512 92 :color sdl:*white* :font *menu-font*)
(dotimes (i (- (n-ship score) 1))
    (setf (x score-ship) (+ 496 (* 40 i)))
    (Draw score-ship)))

;; step6 <Key State>
;; -----------------------------------------------------------------------------------------------
(defclass keystate ()
((%right :initarg :right :initform nil :accessor right)
   (%left :initarg :left :initform nil :accessor left)
   (%up :initarg :up :initform nil :accessor up)
   (%down :initarg :down :initform nil :accessor down)
   (%z :initarg :z :initform nil :accessor z))
(:documentation "The Keystate Class"))

(defgeneric Update-keystate (key boolean keystate))

(defmethod Update-keystate (key boolean keystate)
(cond ((sdl:key= key :SDL-KEY-RIGHT) (setf (right keystate) boolean))
            ((sdl:key= key :SDL-KEY-LEFT) (setf (left keystate) boolean))
            ((sdl:key= key :SDL-KEY-UP) (setf (up keystate) boolean))
            ((sdl:key= key :SDL-KEY-DOWN) (setf (down keystate) boolean))
            ((sdl:key= key :SDL-KEY-Z) (setf (z keystate) boolean))))

(defgeneric Move-ship (ship keystate))

(defmethod Move-ship (ship keystate)
(when (or (= (state ship) 1)
                  (= (state ship) 3))
    (cond ((right keystate) (incf (x ship) (dx ship)))
              ((left keystate) (decf (x ship) (dx ship)))
              ((up keystate) (decf (y ship) (dy ship)))
              ((down keystate) (incf (y ship) (dy ship))))))

;; step7 <Game Field>
;; -----------------------------------------------------------------------------------------------
(defclass game-field ()
((%field-x :initarg :field-x :initform 0 :reader field-x)
   (%field-y :initarg :field-y :initform 0 :reader field-y)
   (%width :initarg :width :initform 480 :reader width)
   (%height :initarg :height :initform 480 :reader height))
(:documentation "The Game-field Class"))

(defgeneric Fix-ship-position (ship game-field))

(defmethod Fix-ship-position (ship game-field)
"ship always inside game-field"
(when (< (x ship) (field-x game-field)) (setf (x ship) (field-x game-field)))
(when (< (y ship) (field-y game-field)) (setf (y ship) (field-y game-field)))
(when (> (x ship) (- (width game-field) 32)) (setf (x ship) (- (width game-field) 32)))
(when (> (y ship) (- (height game-field) 32)) (setf (y ship) (- (height game-field) 32))))

;; step8 <Shot>
;; -----------------------------------------------------------------------------------------------
(defgeneric Move-shot (shot))

(defmethod Move-shot (shot)
  "shot move"
(when (= (state shot) 1) ; shot is alive
    (decf (y shot) (dy shot))) ; shot 16 dot up
    (when (< (y shot) -32) ; out of screen
      (setf (state shot) 0))) ; shot off

(defgeneric Set-shot (shot ship keystate))

(defmethod Set-shot (shot ship keystate)
(when (and (/= (state ship) 2) ; if ship is not explode
                   (= (state shot) 0) ; and shot is dead
                     (eql (z keystate) t)) ; and set z key
    (setf (y shot) (- (y ship) (height shot))) ; set shot position
    (setf (x shot) (x ship))
    (setf (state shot) 1) ; shot on
    (Play-sample *shot-sound*) ; shot sound
    (setf (z keystate) nil))) ; reset z key

;; step9 <Move Enemy>
;; -----------------------------------------------------------------------------------------------
(defparameter *graphic-height* 480)
(defparameter *graphic-width* 480)

(defclass foe ()
((%enemy-list :initarg :enemy-list :initform nil :accessor enemy-list)
(%enemy-shot-list :initarg :enemy-shot-list :initform nil :accessor enemy-shot-list))
(:documentation "The foe Class"))

(defgeneric Move-enemy (ship foe))

(defmethod Move-enemy (ship foe)
(dolist (enemy (enemy-list foe))
(when (= (state enemy) 1)
    (incf (x enemy) (dx enemy))
    (incf (y enemy) (dy enemy))
    (incf (move-cnt enemy) 1)
    (ecase (id enemy)
      (2 (progn ; enemy type1
        (when (> (y enemy) (- *graphic-height* 32))
          (if (> (x enemy) (x ship))
            (setf (dx enemy) -2)
          (setf (dx enemy) 2))
          (setf (dy enemy) -2))
        (when (or (< (x enemy) -32)
                        (> (x enemy) *graphic-width*))
          (setf (state enemy) 0))))
      (3 (progn ; enemy type2
        (when (or (< (x enemy) -32)
                        (> (x enemy) *graphic-width*))
          (setf (state enemy) 0))))
      (4 (progn ; enemy type3
        (when (and (< (x enemy) -32)
                           (= (dx enemy) -3))
          (setf (state enemy) 0))
(when (and (> (x enemy) *graphic-width*)
                             (= (dx enemy) 3))
(setf (state enemy) 0))))))))

;; Step9 <Set Enemy>
;; -----------------------------------------------------------------------------------------------
(defgeneric Set-enemy (timing foe))

(defmethod Set-enemy (timing foe)
  "enemy appear position set"
(when (= (mod (scroll timing) (interval timing)) 0)
    (let ((enemy (make-instance 'entity :id (+ (random 3) 2) :state 0)))
    (push enemy (enemy-list foe)))
      (dolist (enemy (enemy-list foe))
        (when (= (state enemy) 0)
          (setf (state enemy) 1) ; set enemy state alive
        (ecase (id enemy)
          (2 (progn ; enemy type1 appears from top
            (setf (x enemy) (random 448))
            (setf (y enemy) 0)
            (setf (dx enemy) 0)
            (setf (dy enemy) 2)))
          (3 (progn ; enemy type2 appears from bottom
            (setf (x enemy) (random 448))
            (setf (y enemy) *graphic-height*)
            (if (> (x enemy) (- (/ *graphic-width* 2) 16))
              (setf (dx enemy) -2) ; if enemy type2 appears right half
            (setf (dx enemy) 2)) ; if enemy type3 appears left half
            (setf (dy enemy) -1)))
          (4 (progn ; enemy type3 appears from left or right
            (ecase (random 2)
              (0 (progn ; from left
                (setf (x enemy) -32)
                (setf (dx enemy) 3)))
              (1 (progn ; from right
                (setf (x enemy) *graphic-width*)
                (setf (dx enemy) -3)
                (setf (y enemy) (random (/ *graphic-height* 2)))
                (setf (dy enemy) 1)))))))))))

;; Step9 <Remove Dead Enemy>
;; -----------------------------------------------------------------------------------------------
(defgeneric Remove-dead-enemy (foe))

(defmethod Remove-dead-enemy (foe)
"dead enemy remove from list"
(setf (enemy-list foe)
(delete-if #'(lambda (enemy) (= (state enemy) 0)) (enemy-list foe))))

;; Step10 <Move Enemy Shot>
;; -----------------------------------------------------------------------------------------------
(defgeneric Move-enemy-shot (foe))

(defmethod Move-enemy-shot (foe)
  "enemy shot move"
(dolist (enemy-shot (enemy-shot-list foe))
(when (= (state enemy-shot) 1) ; set enemy-shot state alive
    (incf (x enemy-shot) (dx enemy-shot))
    (incf (y enemy-shot) (dy enemy-shot))
    (when (or (< (x enemy-shot) -16)
                    (> (x enemy-shot) *graphic-width*)
                    (< (y enemy-shot) -16)
                    (> (y enemy-shot) *graphic-height*))
      (setf (state enemy-shot) 0)))))

;; Step10 <Set Enemy Shot>
;; -----------------------------------------------------------------------------------------------
(defgeneric Set-enemy-shot (foe))

(defmethod Set-enemy-shot (foe)
  "enemy shot appear position set and move"
(dolist (enemy (enemy-list foe))
    (when (and (= (state enemy) 1)
                       (> (x enemy) 0)
                       (< (x enemy) (- *graphic-width* 32))
                       (> (y enemy) 0)
                       (< (y enemy) (- *graphic-height* 32))
                       (= (mod (move-cnt enemy) 64) 0))
    (let ((enemy-shot (make-instance 'entity :imageid 2 :id 1 :state 0)))
      (push enemy-shot (enemy-shot-list foe)))
      (dolist (enemy-shot (enemy-shot-list foe))
      (when (= (state enemy-shot) 0)
        (setf (y enemy-shot) (+ (y enemy) 8))
        (setf (x enemy-shot) (+ (x enemy) 8))
        (setf (state enemy-shot) 1)
        (ecase (id enemy)
          (2 (progn
            (setf (dx enemy-shot) 0)
            (setf (dy enemy-shot) 6)))
          (3 (progn
            (setf (dx enemy-shot) 0)
            (setf (dy enemy-shot) -6)))
          (4 (progn
            (if (= (dx enemy) -3)
              (setf (dx enemy-shot) -6)
            (setf (dx enemy-shot) 6))
            (setf (dy enemy-shot) 0)))))))))

;; Step10 <Remove Dead Enemy Shot>
;; -----------------------------------------------------------------------------------------------
(defgeneric Remove-dead-enemy-shot (foe))

(defmethod Remove-dead-enemy-shot (foe)
"dead enemy shot remove from list"
(setf (enemy-shot-list foe)
(delete-if #'(lambda (enemy-shot) (= (state enemy-shot) 0)) (enemy-shot-list foe))))

; Step11 <Judge Enemy Shot Hit>
;; -----------------------------------------------------------------------------------------------
(defgeneric Ship-hit-p (ship foe))

(defmethod Ship-hit-p (ship foe)
(when (= (state ship) 1) ; if ship is alive
(let ((hit 0))
    (dolist (enemy (enemy-list foe))
      (when (and (= (state enemy) 1) ; enemies and ship hit
                         (> (+ (x ship) 16) (x enemy))
                         (< (+ (x ship) 16) (+ (x enemy) 31))
                         (> (+ (y ship) 16) (y enemy))
                         (< (+ (y ship) 16) (+ (y enemy) 31)))
        (setf (state enemy) 0
                hit 1)))
      (dolist (enemy-shot (enemy-shot-list foe))
        (when (and (= (state enemy-shot) 1) ; enemies shot and ship hit
                           (> (+ (x ship) 16) (x enemy-shot))
                           (< (+ (x ship) 16) (+ (x enemy-shot) 15))
                           (> (+ (y ship) 16) (y enemy-shot))
                           (< (+ (y ship) 16) (+ (y enemy-shot) 15)))
        (setf (state enemy-shot) 0
                  hit 1)))
      (when (= hit 1)
        (setf (state ship) 2 ; ship is explode
        (explode-cnt ship) 0))))) ; ship explode count 0

;; Step11 <Explode Ship>
;; -----------------------------------------------------------------------------------------------

(defvar *shipbom-sound-flag* nil)
(defgeneric Explode-counter (ship score))

(defmethod Explode-counter (ship score)
(when (= (state ship) 2) ; ship is explode
(when (eql *shipbom-sound-flag* nil)
(setf *shipbom-sound-flag* t)
(Play-sample *shipbom-sound*)) ; shipbom sound
(incf (explode-cnt ship) 1)
(when (= (explode-cnt ship) 100)
(decf (n-ship score) 1)
(when (> (n-ship score) 0)
(setf (state ship) 3 ; set ship revival
*shipbom-sound-flag* nil
(revival-cnt ship) 0
(x ship) (/ (- *graphic-width* 32) 2)
(y ship) (- *graphic-height* 64))))))

;; Step11 <Revive Ship>
;; -----------------------------------------------------------------------------------------------
(defgeneric Revive-counter (ship))

(defmethod Revive-counter (ship)
(when (= (state ship) 3) ; ship is reviving
(incf (revival-cnt ship) 1)
(when (= (revival-cnt ship) 200)
(setf (state ship) 1))))

;; Step11 <Game Over Message>
;; -----------------------------------------------------------------------------------------------
(defgeneric Game-over-message (score))

(defmethod Game-over-message (score) ; message Draw
  "Draw game over message"
(when (= (n-ship score) 0)
    (stop-sound) ; BGM stop
    (sdl:draw-string-solid-* "GAME OVER" 208 232 :color sdl:*white* :font *menu-font*)
(sdl:update-display)
(sleep 5)
(sdl:push-quit-event)))

;; Step12 <Judge Shot Hit>
;; -----------------------------------------------------------------------------------------------
(defgeneric Enemy-hit-p (shot score foe))

(defmethod Enemy-hit-p (shot score foe)
(when (= (state shot) 1) ; if shot state on
(dolist (enemy (enemy-list foe))
    (when (and (= (state enemy) 1) ; if enemy is alive
                       (> (+ (x shot) 31) (x enemy))
                       (< (x shot) (+ (x enemy) 31))
                       (> (+ (y shot) 31) (y enemy))
                       (< (y shot) (+ (y enemy) 31)))
    (setf (state enemy) 2 ; enemy explosion
      (explode-cnt enemy) 0
      (state shot) 0) ; set shot state off
      (incf (score score) 100)))
      (when (> (score score) (highscore score))
        (setf (highscore score) (score score)))))

;; Step12 <Explode enemy>
;; -----------------------------------------------------------------------------------------------
(defvar *enemybom-sound-flag* nil)
(defgeneric Explode-enemy (foe))

(defmethod Explode-enemy (foe)
"enemy explosion while 16 times loop"
(dolist (enemy (enemy-list foe))
(when (= (state enemy) 2)
(when (eql *enemybom-sound-flag* nil)
(setf *enemybom-sound-flag* t)
(Play-sample *enemybom-sound*)) ; enemybom sound
(incf (explode-cnt enemy) 1)
(when (= (explode-cnt enemy) 16) ; enemy explode count 16
(setf (state enemy) 0
*enemybom-sound-flag* nil)))))

;; Step 4 <Scroll Counter>
;; -----------------------------------------------------------------------------------------------
(defgeneric Scroll-counter (timing))

(defmethod Scroll-counter (timing)
(incf (scroll timing))
(when (= (scroll timing) 3072) ; mapchip 96 pieces move
(when (> (interval timing) 32)
(decf (interval timing) 32))))

;; step1 <Game Frame>
;; -----------------------------------------------------------------------------------------------

(defun Common-shooter ()
  "main routine"
(sdl:with-init (sdl:sdl-init-video sdl:sdl-init-audio) ; use video and audio
(sdl:window 640 480 :position #(192 50) ; size 640*480, position x(192) y(50)
                                    :title-caption "THE SHOOTER"
                                    :icon-caption "THE SHOOTER"
                                    :double-buffer T)
                                  ; :fullscreen T)
  ; step 3
(Initialize) ; graphics initialize
  ; step 5
(Set-font) ; set font
  ; step 2
(Open-sound) ; open audio and load sound data
  ; step 2
(Play-music *bg-music*) ; play music
; step 3 - 9
(let((ship (make-instance 'entity :imageid 0 :id 0 :x 224 :y 416 :width 32 :height 32 :dx 4 :dy 4 :state 1))
        (mapchip (make-instance 'object :imageid 1 :id 0))
        (timing (make-instance 'timing)) ; step4 add sentence
        (score-ship (make-instance 'object :imageid 0 :id 0 :x 496 :y 128)) ;step5 add sentence
        (score (make-instance 'score)) ; step5 add sentence
        (keystate (make-instance 'keystate)) ; step6 add sentence
        (game-field (make-instance 'game-field)) ; step7 add sentence
        (shot (make-instance 'entity :imageid 0 :height 32 :dy 16 :id 1 :state 0)) ; step8 add sentence
        (foe (make-instance 'foe)) ; step9 add sentence
　　 (explosion (make-instance 'object :imageid 1 :id 2)) ; step11 add sentence
　　 (enemy-explosion (make-instance 'object :imageid 1 :id 1))) ; step 12 add sentence

(sdl:update-display)
(sdl:with-events (:poll)
    (:quit-event ()
    ; step 2
    (Stop-sound) ; sample and music stop
    (Close-sound) ; close audio
      t)
    ; step 6
    (:key-down-event (:key key)
      (if (sdl:key= key :SDL-KEY-ESCAPE)
          (sdl:push-quit-event)
      (Update-keystate key t keystate)))
    (:key-up-event (:key key)
      (Update-keystate key nil keystate))

    (:idle ()
      ; Game body
      ; step 6
      (Move-ship ship keystate)
      ; step 7
      (Fix-ship-position ship game-field)
      ; step 8
      (Move-shot shot)
      (Set-shot shot ship keystate)
      ; step 4
      (Scroll-background mapchip timing) ; scroll background
      ; step 3
      (when (= (state ship) 1)
        (Draw ship)) ; draw ship
      ; step 8
      (when (= (state shot) 1)
        (Draw shot)) ; draw shot

      ; step 9
      (Move-enemy ship foe)
      (Set-enemy timing foe)
      (dolist (enemy (enemy-list foe))
        (when (= (state enemy) 1)
          (Draw enemy))) ; draw enemy
      (Remove-dead-enemy foe)
      ; step 10
      (Move-enemy-shot foe)
      (Set-enemy-shot foe)
      (dolist (enemy-shot (enemy-shot-list foe))
      (when (= (state enemy-shot) 1)
        (Draw enemy-shot))) ; draw enemy shot
      (Remove-dead-enemy-shot foe)

      ; step 11
      (Ship-hit-p ship foe)
      (Explode-counter ship score)
      (when (= (state ship) 2)
        (setf (x explosion) (- (x ship) 16)
                (y explosion) (- (y ship) 16))
        (Draw explosion)) ; draw ship explosion
      (Revive-counter ship)
      (when (and (= (state ship) 3)
                         (> 5 (mod (revival-cnt ship) 10)))
        (Draw ship)) ; draw ship revival
      ; step 12
      (Enemy-hit-p shot score foe)
      (Explode-enemy foe)
      (dolist (enemy (enemy-list foe))
      (when (= (state enemy) 2)
        (setf (x enemy-explosion) (- (x enemy) 16)
                (y enemy-explosion) (- (y enemy) 16))
      (Draw enemy-explosion))) ; draw enemy explosion
    ; step 5
      (Score-panel score score-ship) ; draw score panel
      ; step 4
      (Scroll-counter timing)