racket/collects/htdch/draw/support.scm
Matthias Felleisen 53b0ed4401 conversion to 4.0 module style
svn: r9482
2008-04-25 22:59:11 +00:00

220 lines
8.7 KiB
Scheme

#lang scheme/gui
(require htdp/draw
lang/posn
mzlib/class
mzlib/unit
profj/libs/java/lang/String
profj/libs/java/lang/Throwable
profj/libs/java/lang/RuntimeException)
(provide world-native@ world-native^ canvas-native@ canvas-native^ support^)
(define-signature world-native^
(endOfTime-java.lang.String-native
endOfWorld-java.lang.String-native
bigBangO-double-native))
(define-signature canvas-native^
(xshow-native
xclose-native
stop-native
copy-native
drawCircle-geometry.Posn-int-colors.IColor-native
drawDisk-geometry.Posn-int-colors.IColor-native
drawRect-geometry.Posn-int-int-colors.IColor-native
drawLine-geometry.Posn-geometry.Posn-colors.IColor-native
drawString-geometry.Posn-java.lang.String-native
))
(define-signature support^ (void-or-true imperative))
;Raises an error if string is null
;check-string: string string string -> boolean
(define (check-string value method argument)
(when (null? value)
(raise-error (format "Method ~a expects a non-null String for ~a argument, given null" method argument)))
#t)
;raises a Java exception with the specified error message
;raise-error: String -> void
(define (raise-error message)
(raise
(create-java-exception RuntimeException message
(lambda (exn str)
(send exn RuntimeException-constructor-java.lang.String str))
(current-continuation-marks))))
(define-unit canvas-native@
(import support^)
(export canvas-native^)
(define-syntax (wrap-start-check stx)
(syntax-case stx ()
[(_ body ...)
#'(with-handlers
((exn:fail?
(lambda (e)
(raise-error
(format
(string-append
"The method show() must be called on the canvas"
"before using any drawing methods [~s]")
(exn-message e))))))
(begin (begin body ...) void-or-true))]))
(define Posn-x-get (dynamic-require 'htdch/geometry/Posn 'Posn-x-get))
(define Posn-y-get (dynamic-require 'htdch/geometry/Posn 'Posn-y-get))
(define (build-posn posnO) (make-posn (Posn-x-get posnO) (Posn-y-get posnO)))
(define (color->symbol colorO) (string->symbol (to-lower-case (send colorO my-name))))
;Raises an error if value less than or equal to 0
;check-arg: num string string -> boolean
(define (check-arg value method argument)
(or (> value 0)
(raise-error
(format "Method ~a expects an int >= 0 for ~a argument, given ~a" method argument value))))
(define (to-lower-case s)
(letrec ((lower
(lambda (s)
(cond
((null? s) s)
(else (cons (char-downcase (car s))
(lower (cdr s))))))))
(list->string (lower (string->list s)))))
(define (xshow-native this accs gets privates)
;; Kathy: it looks like I am working around a bug here.
;; I really wanted to write ([hash-table-get privates 'width] this)
;; but that didn't work at all. 'width is not a key for privates,
;; even though it is a private field. Then I wanted to write
;; ([hash-table-get privates 'width] this), just like in World-native-methods.
;; That failed, too, with an arity error.
(define x (with-method ([g (this Canvas-width-get)]) (g '___)))
(define y (with-method ([g (this Canvas-height-get)]) (g '___)))
(start-and-export x y privates)
void-or-true)
(define (xclose-native this accs gets privates)
(wrap-start-check ([hash-ref privates '%stop]))
void-or-true)
(define (stop-native this accs gets privates)
(wrap-start-check ([hash-ref privates '%end-of-time])))
;; (copy) restores the viewport and the pixmap so that
;; (end-draw-sequence) can copy the pixmap into the viewport.
;; It also clears the pixmap from anything that was on there.
;; design rationale: the closure is created during the initializtion
;; of the world (big-bang) and thus encapsulates access to the actual
;; values of pixmap and viewport. big-bang exists once and for
;; all and thus can't encapsulate the values.
;; Alternative: expose these values as a "token", which big-bang must
;; install. I couldn't figure out how to do this at the time.
(define (copy-native this accs gets privates)
(wrap-start-check ([hash-ref privates 'copy])))
(define (drawCircle-geometry.Posn-int-colors.IColor-native this accs gets privates posn r c)
(wrap-start-check
(check-arg r "drawCircle(Posn, int, IColor)" "second")
([hash-ref privates '%draw-circle] (build-posn posn) r (color->symbol c))))
(define (drawDisk-geometry.Posn-int-colors.IColor-native this accs gets privates posn r c)
(wrap-start-check
(check-arg r "drawDisk(Posn, int, IColor)" "second")
([hash-ref privates '%draw-solid-disk] (build-posn posn) r (color->symbol c))))
(define (drawRect-geometry.Posn-int-int-colors.IColor-native this accs gets privates posn w h c)
(wrap-start-check
(check-arg w "drawRect(Posn, int, int, IColor)" "second")
(check-arg h "drawRect(Posn, int, int, IColor)" "third")
([hash-ref privates '%draw-solid-rect] (build-posn posn) w h (color->symbol c))))
(define (drawLine-geometry.Posn-geometry.Posn-colors.IColor-native this accs gets privates p0 p1 c)
(wrap-start-check
([hash-ref privates '%draw-solid-line] (build-posn p0) (build-posn p1) (color->symbol c))))
(define (drawString-geometry.Posn-java.lang.String-native this accs gets privates p s)
(define _ (check-string s "drawString(Posn, String)" "second"))
(define s* (send s get-mzscheme-string))
(wrap-start-check
([hash-ref privates '%draw-string] (build-posn p) s*)))
#;
(define (clearCircle-geometry.Posn-int-colors.IColor-native this accs gets privates p r c)
(wrap-start-check
(check-arg r "clearCircle(Posn, int, IColor)" "second")
([hash-table-get privates '%clear-circle] (build-posn p) r (color->symbol c))))
#;
(define (clearDisk-geometry.Posn-int-colors.IColor-native this accs gets privates p r c)
(wrap-start-check
(check-arg r "clearDisk(Posn, int, IColor)" "second")
([hash-table-get privates '%clear-solid-disk] (build-posn p) r (color->symbol c))))
#;
(define (clearRect-geometry.Posn-int-int-colors.IColor-native this accs gets privates p w h c)
(wrap-start-check
(check-arg w "clearRect(Posn, int, int, IColor)" "second")
(check-arg h "clearRect(Posn, int, int, IColor)" "third")
([hash-table-get privates '%clear-solid-rect] (build-posn p) w h (color->symbol c))))
#;
(define (clearLine-geometry.Posn-geometry.Posn-colors.IColor-native this accs gets privates p0 p1 c)
(wrap-start-check
([hash-table-get privates '%clear-solid-line] (build-posn p0) (build-posn p1) (color->symbol c))))
)
(define-unit world-native@
(import support^)
(export world-native^)
(define (bigBangO-double-native this accs gets privates i)
(define theCanvas ((hash-ref accs 'theCanvas) this))
(define setCanvas (hash-ref gets 'theCanvas))
(define width (with-method ([g (theCanvas Canvas-width-get)]) (g '___)))
(define height (with-method ([g (theCanvas Canvas-height-get)]) (g '___)))
;; call only *after* start
(define (on-event world0 th)
(begin-draw-sequence)
(send theCanvas copy)
(let ([world (imperative (th) world0)])
(unless (eq? world0 world)
(setCanvas world theCanvas))
(send world draw)
(end-draw-sequence)
world))
(send theCanvas show)
(big-bang i this)
(on-tick-event
(lambda (world)
(on-event world (lambda () (send world onTick)))))
(on-key-event
(lambda (ke world)
(define ke* (make-java-string (if (char? ke) (string ke) (symbol->string ke))))
(on-event world (lambda () (send world onKeyEvent-java.lang.String ke*)))))
void-or-true)
(define (endOfTime-java.lang.String-native this accs gets privates s)
(define _ (check-string s "endOfTime(String)" "first"))
(define t (send s get-mzscheme-string))
(define theCanvas ((hash-ref accs 'theCanvas) this))
(parameterize ([current-eventspace (make-eventspace)])
(message-box "end of world" (send s get-mzscheme-string)))
(unless (null? theCanvas)
(send theCanvas stop))
#t)
(define (endOfWorld-java.lang.String-native this accs gets privates s)
(define theCanvas ((hash-ref accs 'theCanvas) this))
(define _ (check-string s "endOfWorld(String)" "first"))
(parameterize ([current-eventspace (make-eventspace)])
(message-box "end of world" (send s get-mzscheme-string)))
(unless (null? theCanvas)
(send theCanvas stop))
this))