racket/collects/2htdp/private/image-more.rkt

1531 lines
60 KiB
Racket

#lang racket/base
(require mrlib/image-core
"img-err.rkt"
racket/match
racket/contract
racket/class
(except-in racket/draw
make-pen make-color)
;(only-in racket/gui/base frame% canvas% slider% horizontal-panel% button%)
htdp/error
racket/math
(for-syntax racket/base
racket/list)
lang/posn
net/url)
;; for testing
; (require racket/gui/base)
#;
(define (show-image arg [extra-space 0])
(letrec ([g (to-img arg)]
[f (new frame% [label ""])]
[c (new canvas%
[parent f]
[min-width (+ extra-space (image-width g))]
[min-height (+ extra-space (image-height g))]
[paint-callback
(λ (c dc)
(send dc set-smoothing 'aligned)
(let-values ([(w h) (send c get-client-size)])
(let ([scale (send sl get-value)])
(send dc set-scale scale scale)
(render-image
g
dc
(inexact->exact (floor (- (/ w 2 scale) (/ (get-right g) 2))))
(inexact->exact (floor (- (/ h 2 scale) (/ (get-bottom g) 2))))))))])]
[min-scale 1]
[max-scale 10]
[sl (new slider%
[label "Scale factor"]
[parent f]
[min-value min-scale]
[max-value max-scale]
[callback (λ ignore (send c refresh))])]
[bp (new horizontal-panel%
[parent f]
[alignment '(center center)]
[stretchable-height #f])]
[scale-adjust
(λ (f)
(send sl set-value
(max min-scale (min max-scale (f (send sl get-value)))))
(send c refresh))])
(send (new button%
[label ""]
[callback (λ x (scale-adjust sub1))]
[parent bp]) min-width 100)
(send (new button%
[label "2"]
[callback (λ x (scale-adjust add1))]
[parent bp]) min-width 100)
(send f show #t)))
;; the obfuscation in the width and height defaults is so that error checking happens in the right order
(define/chk (save-image image
filename
[width (if (image? image) (image-width image) 0)]
[height (if (image? image) (image-height image) 0)])
(let* ([bm (make-bitmap (inexact->exact (ceiling width))
(inexact->exact (ceiling height)))]
[bdc (make-object bitmap-dc% bm)])
(send bdc set-smoothing 'aligned)
(send bdc erase)
(render-image image bdc 0 0)
(send bdc set-bitmap #f)
(send bm save-file filename 'png)))
(define/chk (save-svg-image image
filename
[width (if (image? image) (image-width image) 0)]
[height (if (image? image) (image-height image) 0)])
(call-with-output-file filename
(λ (port)
(define sdc (new svg-dc% [width width] [height height] [output port]))
(send sdc start-doc "")
(send sdc start-page)
(send sdc set-smoothing 'aligned)
(render-image image sdc 0 0)
(send sdc end-page)
(send sdc end-doc))
#:exists 'truncate))
(define (get-right img) (bb-right (send img get-bb)))
(define (get-bottom img) (bb-bottom (send img get-bb)))
(define (get-baseline img) (bb-baseline (send img get-bb)))
;
;
;
; ;;
; ;;
; ;;
; ;;;; ;;; ;;;;;; ;; ; ;; ;;;;; ;;; ;
; ;; ;; ;; ;;;; ;; ;;;; ;; ; ;; ;; ;;
; ;;; ;; ;;;; ;;;;;; ;; ;; ;;;; ;;;;
; ;;; ;; ;;;; ;; ;; ;; ;; ;; ;;;
; ;; ;; ;;; ;;; ; ;; ;; ;; ;; ;;;
; ;;;; ;; ;;;; ;; ;; ;;;;;;; ;;
; ;;
; ;
; ;;
;; scale : number image -> image
(define/chk (scale factor image)
(scale-internal factor factor image))
(define/chk (scale/xy x-factor y-factor image)
(scale-internal x-factor y-factor image))
(define (scale-internal x-factor y-factor image)
(let ([ph (send image get-pinhole)])
(make-image (make-scale x-factor y-factor (image-shape image))
(make-bb (* x-factor (get-right image))
(* y-factor (get-bottom image))
(* y-factor (get-baseline image)))
#f
(and ph
(make-point (* x-factor (point-x ph))
(* y-factor (point-y ph)))))))
;; overlay : image image image ... -> image
;; places images on top of each other with their upper left corners aligned.
;; last one goes on the bottom
(define/chk (overlay image image2 . image3)
(overlay/internal 'middle 'middle image (cons image2 image3)))
;; underlay : image image image ... -> image
(define/chk (underlay image image2 . image3)
(let ([imgs (reverse (list* image image2 image3))])
(overlay/internal 'middle 'middle (car imgs) (cdr imgs))))
;; overlay/align : string string image image image ... -> image
;; the first string has to be one of "center" "middle" "left" or "right" (or symbols)
;; the second string has to be one of "center" "middle" "top" "bottom" or "baseline" (or symbols)
;; behaves like overlay, but lines up the images in the various places.
;; overlay without string arguments is the same as passing "left" and "top"
;; for the two string arguments. Passing, eg, "center" "center" lines the
;; images up at their centers.
(define/chk (overlay/align x-place y-place image image2 . image3)
(when (or (eq? x-place 'pinhole) (eq? y-place 'pinhole))
(check-dependencies 'overlay/align
(and (send image get-pinhole)
(send image2 get-pinhole)
(andmap (λ (x) (send x get-pinhole))
image3))
"when x-place or y-place is ~e or ~e, then all of the arguments must have pinholes"
'pinhole "pinhole"))
(overlay/internal x-place y-place image (cons image2 image3)))
(define/chk (underlay/align x-place y-place image image2 . image3)
(when (or (eq? x-place 'pinhole) (eq? y-place 'pinhole))
(check-dependencies 'underlay/align
(and (send image get-pinhole)
(send image2 get-pinhole)
(andmap (λ (x) (send x get-pinhole))
image3))
"when x-place or y-place is ~e or ~e, then all of the arguments must have pinholes"
'pinhole "pinhole"))
(let ([imgs (reverse (list* image image2 image3))])
(overlay/internal x-place y-place (car imgs) (cdr imgs))))
(define/chk (overlay/pinhole image1 image2 . image3)
(overlay/internal 'pinhole 'pinhole
(maybe-center-pinhole image1)
(map maybe-center-pinhole (cons image2 image3))))
(define/chk (underlay/pinhole image1 image2 . image3)
(let ([imgs (map maybe-center-pinhole (reverse (list* image1 image2 image3)))])
(overlay/internal 'pinhole 'pinhole
(car imgs)
(cdr imgs))))
(define (maybe-center-pinhole img)
(if (send img get-pinhole)
img
(center-pinhole img)))
(define (overlay/internal x-place y-place fst rst)
(let loop ([fst fst]
[rst rst])
(cond
[(null? rst) fst]
[else
(let* ([fst-x-spot (find-x-spot x-place fst)]
[fst-y-spot (find-y-spot y-place fst)]
[snd-x-spot (find-x-spot x-place (car rst))]
[snd-y-spot (find-y-spot y-place (car rst))]
[dx (- fst-x-spot snd-x-spot)]
[dy (- fst-y-spot snd-y-spot)])
(loop (overlay/δ fst
(if (< dx 0) (- dx) 0)
(if (< dy 0) (- dy) 0)
(car rst)
(if (< dx 0) 0 dx)
(if (< dy 0) 0 dy)
#t)
(cdr rst)))])))
(define (find-x-spot x-place image)
(case x-place
[(left) 0]
[(middle) (/ (get-right image) 2)]
[(right) (get-right image)]
[(pinhole) (point-x (send image get-pinhole))]
[else (error 'find-x-spot "~s" x-place)]))
(define (find-y-spot y-place image)
(case y-place
[(top) 0]
[(middle) (/ (get-bottom image) 2)]
[(bottom) (get-bottom image)]
[(baseline) (get-baseline image)]
[(pinhole) (point-y (send image get-pinhole))]
[else (error 'find-y-spot "~s" y-place)]))
;; overlay/xy : image number number image -> image
;; places images on top of each other with their upper-left corners offset by the two numbers
(define/chk (overlay/xy image dx dy image2)
(overlay/δ image
(if (< dx 0) (- dx) 0)
(if (< dy 0) (- dy) 0)
image2
(if (< dx 0) 0 dx)
(if (< dy 0) 0 dy)
#t))
(define/chk (underlay/xy image dx dy image2)
(overlay/δ image2
(if (< dx 0) 0 dx)
(if (< dy 0) 0 dy)
image
(if (< dx 0) (- dx) 0)
(if (< dy 0) (- dy) 0)
#f))
(define (overlay/δ image1 dx1 dy1 image2 dx2 dy2 first-pinhole?)
(make-image (make-overlay (make-translate dx1 dy1 (image-shape image1))
(make-translate dx2 dy2 (image-shape image2)))
(make-bb (max (+ (get-right image1) dx1)
(+ (get-right image2) dx2))
(max (+ (get-bottom image1) dy1)
(+ (get-bottom image2) dy2))
(max (+ (get-baseline image1) dy1)
(+ (get-baseline image2) dy2)))
#f
(if first-pinhole?
(let ([ph (send image1 get-pinhole)])
(and ph
(make-point (+ (point-x ph) dx1)
(+ (point-y ph) dy1))))
(let ([ph (send image2 get-pinhole)])
(and ph
(make-point (+ (point-x ph) dx2)
(+ (point-y ph) dy2)))))))
;; beside : image image image ... -> image
;; places images in a single horizontal row, top aligned
(define/chk (beside image1 image2 . image3)
(beside/internal 'middle image1 (cons image2 image3)))
;; beside/align : string image image image ... -> image
;; places images in a horizontal row where the vertical alignment is
;; covered by the string argument
(define/chk (beside/align y-place image1 image2 . image3)
(when (eq? y-place 'pinhole)
(check-dependencies 'beside/align
(and (send image1 get-pinhole)
(send image2 get-pinhole)
(andmap (λ (x) (send x get-pinhole))
image3))
"when y-place is ~e or ~e, then all of the arguments must have pinholes"
'pinhole "pinhole"))
(beside/internal y-place image1 (cons image2 image3)))
(define (beside/internal y-place fst rst)
(let loop ([fst fst]
[rst rst])
(cond
[(null? rst) fst]
[else
(let* ([snd (car rst)]
[fst-y-spot (find-y-spot y-place fst)]
[snd-y-spot (find-y-spot y-place (car rst))]
[dy (- fst-y-spot snd-y-spot)])
(loop (overlay/δ fst
0
(if (< dy 0) (- dy) 0)
(car rst)
(get-right fst)
(if (< dy 0) 0 dy)
#t)
(cdr rst)))])))
;; above : image image image ... -> image
;; places images in a single vertical row, left aligned
(define/chk (above image1 image2 . image3)
(above/internal 'middle image1 (cons image2 image3)))
;; beside/align : string image image image ... -> image
;; places images in a horizontal row where the vertical alignment is
;; covered by the string argument
(define/chk (above/align x-place image1 image2 . image3)
(when (eq? x-place 'pinhole)
(check-dependencies 'above/align
(and (send image1 get-pinhole)
(send image2 get-pinhole)
(andmap (λ (x) (send x get-pinhole))
image3))
"when x-place is ~e or ~e, then all of the arguments must have pinholes"
'pinhole "pinhole"))
(above/internal x-place image1 (cons image2 image3)))
(define (above/internal x-place fst rst)
(let loop ([fst fst]
[rst rst])
(cond
[(null? rst) fst]
[else
(let* ([snd (car rst)]
[fst-x-spot (find-x-spot x-place fst)]
[snd-x-spot (find-x-spot x-place (car rst))]
[dx (- fst-x-spot snd-x-spot)])
(loop (overlay/δ fst
(if (< dx 0) (- dx) 0)
0
(car rst)
(if (< dx 0) 0 dx)
(get-bottom fst)
#t)
(cdr rst)))])))
(define/chk (overlay/offset image1 dx dy image2)
(overlay/offset/internal 'middle 'middle image1 dx dy image2))
(define/chk (overlay/align/offset x-place y-place image1 dx dy image2)
(overlay/offset/internal x-place y-place image1 dx dy image2))
(define/chk (underlay/offset image1 dx dy image2)
(overlay/offset/internal 'middle 'middle image2 (- dx) (- dy) image1))
(define/chk (underlay/align/offset x-place y-place image1 dx dy image2)
(overlay/offset/internal x-place y-place image2 (- dx) (- dy) image1))
(define (overlay/offset/internal x-place y-place fst orig-dx orig-dy snd)
(let* ([fst-x-spot (find-x-spot x-place fst)]
[fst-y-spot (find-y-spot y-place fst)]
[snd-x-spot (find-x-spot x-place snd)]
[snd-y-spot (find-y-spot y-place snd)]
[dx (+ (- fst-x-spot snd-x-spot) orig-dx)]
[dy (+ (- fst-y-spot snd-y-spot) orig-dy)])
(overlay/δ fst
(if (< dx 0) (- dx) 0)
(if (< dy 0) (- dy) 0)
snd
(if (< dx 0) 0 dx)
(if (< dy 0) 0 dy)
#t)))
;
;
;
; ;;;; ;; ;
; ;;;; ;; ;;
; ;;;;; ;;;; ;;;;;;; ;;;; ;;;;;;; ;;;; ;;; ;;;;;;; ;;;;; ;;;; ;;; ;;; ;;;;;
; ;;;;;; ;;;;;; ;;;;;;;;;;;;; ;;;;;;;; ;;;; ;;;;;;;;; ;;;;;;;; ;;;;;; ;;;;;; ;;;;;;; ;;;;;;
; ;;;;;;; ;;;;;;;; ;;;; ;;; ;;;; ;;;;;;;;; ;;;; ;;;; ;;;; ;;;; ;;;; ;;;;;;;; ;;;; ;; ;;;;
; ;;;; ;;;; ;;; ;;;; ;;; ;;;; ;;;; ;;;; ;;;; ;;;; ;;;; ;;;;;;; ;;;; ;;;; ;;; ;;;; ;;;;
; ;;;;;;; ;;;;;;;; ;;;; ;;; ;;;; ;;;;;;;;; ;;;; ;;;; ;;;; ;; ;;;; ;;;;; ;;;;;;;; ;;;; ;;;;
; ;;;;;; ;;;;;; ;;;; ;;; ;;;; ;;;;;;;; ;;;; ;;;; ;;;; ;;;;;;;; ;;;;; ;;;;;; ;;;; ;;;;;;
; ;;;;; ;;;; ;;;; ;;; ;;;; ;;;;;;; ;;;; ;;;; ;;;; ;; ;;;; ;;;; ;;;; ;;;; ;;;;;
;
;
;
;; crop : number number number number image -> image
;; crops an image to be w x h from (x,y)
(define/chk (crop x1 y1 width height image)
(crop/internal x1 y1 width height image))
(define (crop/internal x1 y1 width height image)
(let ([points (rectangle-points width height)]
[ph (send image get-pinhole)])
(make-image (make-crop points
(make-translate (- x1) (- y1) (image-shape image)))
(make-bb width
height
(min height (get-baseline image)))
#f
(and ph
(make-point (- (point-x ph) x1)
(- (point-y ph) y1))))))
;; place-image : image x y scene -> scene
(define/chk (place-image image1 x1 y1 image2)
(place-image/internal image1 x1 y1 image2 'middle 'middle))
(define/chk (place-image/align image1 x1 y1 x-place y-place image2)
(when (or (eq? x-place 'pinhole) (eq? y-place 'pinhole))
(check-dependencies 'place-image/align
(send image1 get-pinhole)
"when x-place or y-place is ~e or ~e, the the first image argument must have a pinhole"
'pinhole "pinhole"))
(place-image/internal image1 x1 y1 image2 x-place y-place))
(define (place-image/internal image orig-dx orig-dy scene x-place y-place)
(let ([dx (- orig-dx (find-x-spot x-place image))]
[dy (- orig-dy (find-y-spot y-place image))])
(crop/internal
(if (< dx 0) (- dx) 0)
(if (< dy 0) (- dy) 0)
(get-right scene)
(get-bottom scene)
(overlay/δ image
(if (< dx 0) 0 dx)
(if (< dy 0) 0 dy)
scene
(if (< dx 0) (- dx) 0)
(if (< dy 0) (- dy) 0)
#f))))
(define/chk (scene+line image x1 y1 x2 y2 color)
(let* ([dx (abs (min 0 x1 x2))]
[dy (abs (min 0 y1 y2))])
(make-image (make-overlay
(make-crop (rectangle-points (get-right image) (get-bottom image))
(make-line-segment (make-point x1 y1) (make-point x2 y2) color))
(image-shape image))
(image-bb image)
#f
(send image get-pinhole))))
(define/chk (scene+curve image x1 y1 angle1 pull1 x2 y2 angle2 pull2 color)
(let* ([dx (abs (min 0 x1 x2))]
[dy (abs (min 0 y1 y2))])
(make-image (make-overlay
(make-crop (rectangle-points (get-right image) (get-bottom image))
(make-curve-segment (make-point x1 y1) angle1 pull1
(make-point x2 y2) angle2 pull2
color))
(image-shape image))
(image-bb image)
#f
(send image get-pinhole))))
;; frame : image -> image
;; draws a black frame around a image where the bounding box is
;; (useful for debugging images)
(define/chk (frame image)
(make-image (make-overlay (image-shape
(crop 0 0
(get-right image)
(get-bottom image)
(rectangle (get-right image)
(get-bottom image)
'outline
(pen "black" 2 'solid 'round 'round))))
(image-shape image))
(make-bb (get-right image)
(get-bottom image)
(get-baseline image))
#f
(send image get-pinhole)))
;; scale : I number -> I
;; scales the I by the given factor
;; rotate : number I -> I
;; rotates the I around the top-left corner by the given angle (in degrees)
(define/chk (rotate angle image)
(let* ([rotated-shape (rotate-normalized-shape
angle
(send image get-normalized-shape))]
[ltrb (normalized-shape-bb rotated-shape)]
[ph (send image get-pinhole)])
(make-image (make-translate (- (ltrb-left ltrb)) (- (ltrb-top ltrb)) rotated-shape)
(make-bb (- (ltrb-right ltrb) (ltrb-left ltrb))
(- (ltrb-bottom ltrb) (ltrb-top ltrb))
(- (ltrb-bottom ltrb) (ltrb-top ltrb)))
#f
(and ph
(let ([rp (rotate-point ph angle)])
(make-point (- (point-x rp) (ltrb-left ltrb))
(- (point-y rp) (ltrb-top ltrb))))))))
(define/contract (rotate-normalized-shape angle shape)
(-> number? normalized-shape? normalized-shape?)
(cond
[(overlay? shape)
(let ([top-shape (rotate-normalized-shape angle (overlay-top shape))]
[bottom-shape (rotate-cn-or-simple-shape angle (overlay-bottom shape))])
(make-overlay top-shape bottom-shape))]
[else
(rotate-cn-or-simple-shape angle shape)]))
(define/contract (rotate-cn-or-simple-shape angle shape)
(-> number? cn-or-simple-shape? cn-or-simple-shape?)
(cond
[(crop? shape)
(make-crop (rotate-points (crop-points shape) angle)
(rotate-normalized-shape angle (crop-shape shape)))]
[else
(rotate-simple angle shape)]))
;; rotate-simple : angle simple-shape -> simple-shape
(define/contract (rotate-simple θ simple-shape)
(-> number? simple-shape? simple-shape?)
(cond
[(line-segment? simple-shape)
(make-line-segment (rotate-point (line-segment-start simple-shape)
θ)
(rotate-point (line-segment-end simple-shape)
θ)
(line-segment-color simple-shape))]
[(curve-segment? simple-shape)
(make-curve-segment (rotate-point (curve-segment-start simple-shape)
θ)
(bring-between (+ (curve-segment-s-angle simple-shape) θ) 360)
(curve-segment-s-pull simple-shape)
(rotate-point (curve-segment-end simple-shape)
θ)
(bring-between (+ (curve-segment-e-angle simple-shape) θ) 360)
(curve-segment-e-pull simple-shape)
(curve-segment-color simple-shape))]
[(polygon? simple-shape)
(make-polygon (rotate-points (polygon-points simple-shape) θ)
(polygon-mode simple-shape)
(polygon-color simple-shape))]
[else
(let* ([unrotated (translate-shape simple-shape)]
[rotated (rotate-atomic θ unrotated)])
(let-values ([(dx dy)
(c->xy (* (degrees->complex θ)
(xy->c (translate-dx simple-shape)
(translate-dy simple-shape))))])
(make-translate dx dy rotated)))]))
(struct ltrb (left top right bottom) #:transparent)
(define (union-ltrb ltrb1 ltrb2)
(ltrb (min (ltrb-left ltrb1) (ltrb-left ltrb2))
(min (ltrb-top ltrb1) (ltrb-top ltrb2))
(max (ltrb-right ltrb1) (ltrb-right ltrb2))
(max (ltrb-bottom ltrb1) (ltrb-bottom ltrb2))))
;; only intersection if they already overlap.
(define (intersect-ltrb ltrb1 ltrb2)
(ltrb (max (ltrb-left ltrb1) (ltrb-left ltrb2))
(max (ltrb-top ltrb1) (ltrb-top ltrb2))
(min (ltrb-right ltrb1) (ltrb-right ltrb2))
(min (ltrb-bottom ltrb1) (ltrb-bottom ltrb2))))
(define/contract (normalized-shape-bb shape)
(-> normalized-shape? ltrb?)
(cond
[(overlay? shape)
(let ([top-ltrb (normalized-shape-bb (overlay-top shape))]
[bottom-ltrb (cn-or-simple-shape-bb (overlay-bottom shape))])
(union-ltrb top-ltrb bottom-ltrb))]
[else
(cn-or-simple-shape-bb shape)]))
(define/contract (cn-or-simple-shape-bb shape)
(-> cn-or-simple-shape? ltrb?)
(cond
[(crop? shape)
(let ([ltrb (normalized-shape-bb (crop-shape shape))]
[crop-ltrb (points->ltrb (crop-points shape))])
(intersect-ltrb crop-ltrb ltrb))]
[else
(simple-bb shape)]))
;; simple-bb : simple-shape -> ltrb
;; returns the bounding box of 'shape'
;; (only called for rotated shapes, so bottom=baseline)
(define/contract (simple-bb simple-shape)
(-> simple-shape? ltrb?)
(cond
[(line-segment? simple-shape)
(let ([x1 (point-x (line-segment-start simple-shape))]
[y1 (point-y (line-segment-start simple-shape))]
[x2 (point-x (line-segment-end simple-shape))]
[y2 (point-y (line-segment-end simple-shape))])
(ltrb (min x1 x2)
(min y1 y2)
(+ (max x1 x2) 1)
(+ (max y1 y2) 1)))]
[(curve-segment? simple-shape)
(let ([x1 (point-x (curve-segment-start simple-shape))]
[y1 (point-y (curve-segment-start simple-shape))]
[x2 (point-x (curve-segment-end simple-shape))]
[y2 (point-y (curve-segment-end simple-shape))])
(ltrb (min x1 x2)
(min y1 y2)
(+ (max x1 x2) 1)
(+ (max y1 y2) 1)))]
[(polygon? simple-shape)
(points->ltrb (polygon-points simple-shape))]
[else
(let ([dx (translate-dx simple-shape)]
[dy (translate-dy simple-shape)])
(let-values ([(l t r b) (np-atomic-bb (translate-shape simple-shape))])
(ltrb (+ l dx)
(+ t dy)
(+ r dx)
(+ b dy))))]))
(define (points->ltrb points)
(let-values ([(left top right bottom) (points->ltrb-values points)])
(ltrb left top right bottom)))
(define/contract (np-atomic-bb atomic-shape)
(-> np-atomic-shape? (values number? number? number? number?))
(cond
[(ellipse? atomic-shape)
(let ([θ (ellipse-angle atomic-shape)])
(let-values ([(w h) (ellipse-rotated-size (ellipse-width atomic-shape)
(ellipse-height atomic-shape)
(degrees->radians θ))])
(values (- (/ w 2))
(- (/ h 2))
(/ w 2)
(/ h 2))))]
[(text? atomic-shape)
(let-values ([(w h a d) (send text-sizing-bm get-text-extent
(text-string atomic-shape)
(text->font atomic-shape))])
(rotated-rectangular-bounding-box w h (text-angle atomic-shape)))]
[(flip? atomic-shape)
(let* ([bitmap (flip-shape atomic-shape)]
[bb (ibitmap-raw-bitmap bitmap)])
(let-values ([(l t r b)
(rotated-rectangular-bounding-box (* (send bb get-width) (ibitmap-x-scale bitmap))
(* (send bb get-height) (ibitmap-y-scale bitmap))
(ibitmap-angle bitmap))])
(values l t r b)))]
[else
(eprintf "using bad bounding box for ~s\n" atomic-shape)
(values 0 0 100 100)]))
(define (rotated-rectangular-bounding-box w h θ)
(let*-values ([(ax ay) (rotate-xy (- (/ w 2)) (- (/ h 2)) θ)]
[(bx by) (rotate-xy (- (/ w 2)) (/ h 2) θ)]
[(cx cy) (rotate-xy (/ w 2) (- (/ h 2)) θ)]
[(dx dy) (rotate-xy (/ w 2) (/ h 2) θ)])
(values (min ax bx cx dx)
(min ay by cy dy)
(max ax bx cx dx)
(max ay by cy dy))))
(define (rotate-points in-points θ)
(let* ([cs (map point->c in-points)]
[vectors (points->vectors cs)]
[rotated-vectors (map (λ (c) (rotate-c c θ)) vectors)]
[points (vectors->points rotated-vectors)])
points))
(define (points->vectors orig-points)
(let loop ([points (cons 0 orig-points)])
(cond
[(null? (cdr points)) '()]
[else
(cons (- (cadr points) (car points))
(loop (cdr points)))])))
(define (vectors->points vecs)
(let loop ([vecs vecs]
[p 0])
(cond
[(null? vecs) '()]
[else
(let ([next-p (+ (car vecs) p)])
(cons (c->point next-p)
(loop (cdr vecs)
next-p)))])))
(define (center-point np-atomic-shape)
(let-values ([(l t r b) (np-atomic-bb np-atomic-shape)])
(xy->c (/ (- r l) 2)
(/ (- b t) 2))))
;; rotate-atomic : angle np-atomic-shape -> np-atomic-shape
(define (rotate-atomic θ atomic-shape)
(-> number? np-atomic-shape? np-atomic-shape?)
(cond
[(ellipse? atomic-shape)
(cond
[(= (ellipse-width atomic-shape)
(ellipse-height atomic-shape))
atomic-shape]
[else
(let ([new-angle (bring-between (+ θ (ellipse-angle atomic-shape)) 180)])
(cond
[(< new-angle 90)
(make-ellipse (ellipse-width atomic-shape)
(ellipse-height atomic-shape)
new-angle
(ellipse-mode atomic-shape)
(ellipse-color atomic-shape))]
[else
(make-ellipse (ellipse-height atomic-shape)
(ellipse-width atomic-shape)
(- new-angle 90)
(ellipse-mode atomic-shape)
(ellipse-color atomic-shape))]))])]
[(text? atomic-shape)
(make-text (text-string atomic-shape)
(bring-between (+ θ (text-angle atomic-shape)) 360)
(text-y-scale atomic-shape)
(text-color atomic-shape)
(text-size atomic-shape)
(text-face atomic-shape)
(text-family atomic-shape)
(text-style atomic-shape)
(text-weight atomic-shape)
(text-underline atomic-shape))]
[(flip? atomic-shape)
(let ([bitmap (flip-shape atomic-shape)]
[flipped? (flip-flipped? atomic-shape)])
(make-flip flipped?
(make-ibitmap (ibitmap-raw-bitmap bitmap)
(bring-between (if flipped?
(+ (ibitmap-angle bitmap) θ)
(- (ibitmap-angle bitmap) θ))
360)
(ibitmap-x-scale bitmap)
(ibitmap-y-scale bitmap)
(make-hash))))]))
;; rotate-point : point angle -> point
(define (rotate-point p θ)
(let-values ([(x y) (rotate-xy (point-x p) (point-y p) θ)])
(make-point x y)))
(define (rotate-c c θ)
(* (degrees->complex θ) c))
(define (degrees->complex θ)
(unless (and (<= 0 θ)
(< θ 360))
(error 'degrees->complex "~s" θ))
(case (and (integer? θ) (modulo θ 360))
[(0) 1+0i]
[(90) 0+1i]
[(180) -1+0i]
[(270) 0-1i]
[else (make-polar 1 (degrees->radians θ))]))
;; rotate-xy : x,y angle -> x,y
(define (rotate-xy x y θ)
(c->xy (rotate-c (xy->c x y) θ)))
(define (xy->c x y) (make-rectangular x (- y)))
(define (c->xy c)
(values (real-part c)
(- (imag-part c))))
(define (point->c p) (xy->c (point-x p) (point-y p)))
(define (c->point c)
(let-values ([(x y) (c->xy c)])
(make-point x y)))
;; bring-between : rational integer -> rational
;; returns a number that is much like the modulo of 'x' and 'upper-bound',
;; since modulo only works on integers
(define (bring-between x upper-bound)
(let* ([x-floor (floor x)]
[fraction (- x x-floor)])
(+ (modulo x-floor upper-bound)
fraction)))
(define/chk (flip-horizontal image)
(rotate 90 (flip-vertical (rotate -90 image))))
(define/chk (flip-vertical image)
(let* ([flipped-shape (flip-normalized-shape
(send image get-normalized-shape))]
[ltrb (normalized-shape-bb flipped-shape)]
[ph (send image get-pinhole)])
(make-image (make-translate (- (ltrb-left ltrb)) (- (ltrb-top ltrb)) flipped-shape)
(make-bb (- (ltrb-right ltrb) (ltrb-left ltrb))
(- (ltrb-bottom ltrb) (ltrb-top ltrb))
(- (ltrb-bottom ltrb) (ltrb-top ltrb)))
#f
(and ph
(make-point (+ (point-x ph) (- (ltrb-left ltrb)))
(+ (- (point-y ph)) (- (ltrb-top ltrb))))))))
(define/contract (flip-normalized-shape shape)
(-> normalized-shape? normalized-shape?)
(cond
[(overlay? shape)
(let ([top-shape (flip-normalized-shape (overlay-top shape))]
[bottom-shape (flip-cn-or-simple-shape (overlay-bottom shape))])
(make-overlay top-shape bottom-shape))]
[else
(flip-cn-or-simple-shape shape)]))
(define/contract (flip-cn-or-simple-shape shape)
(-> cn-or-simple-shape? cn-or-simple-shape?)
(cond
[(crop? shape)
(make-crop (flip-points (crop-points shape))
(flip-normalized-shape (crop-shape shape)))]
[else
(flip-simple shape)]))
(define/contract (flip-simple simple-shape)
(-> simple-shape? simple-shape?)
(cond
[(line-segment? simple-shape)
(make-line-segment (flip-point (line-segment-start simple-shape))
(flip-point (line-segment-end simple-shape))
(line-segment-color simple-shape))]
[(curve-segment? simple-shape)
(make-curve-segment (flip-point (curve-segment-start simple-shape))
(bring-between (- (curve-segment-s-angle simple-shape)) 360)
(curve-segment-s-pull simple-shape)
(flip-point (curve-segment-end simple-shape))
(bring-between (- (curve-segment-e-angle simple-shape)) 360)
(curve-segment-e-pull simple-shape)
(curve-segment-color simple-shape))]
[(polygon? simple-shape)
(make-polygon (flip-points (polygon-points simple-shape))
(polygon-mode simple-shape)
(polygon-color simple-shape))]
[else
(make-translate (translate-dx simple-shape)
(- (translate-dy simple-shape))
(flip-atomic (translate-shape simple-shape)))]))
(define/contract (flip-atomic atomic-shape)
(-> np-atomic-shape? np-atomic-shape?)
(cond
[(ellipse? atomic-shape)
(cond
[(= (ellipse-width atomic-shape)
(ellipse-height atomic-shape))
atomic-shape]
[else
(let ([new-angle (bring-between (- 180 (ellipse-angle atomic-shape)) 180)])
(cond
[(< new-angle 90)
(make-ellipse (ellipse-width atomic-shape)
(ellipse-height atomic-shape)
new-angle
(ellipse-mode atomic-shape)
(ellipse-color atomic-shape))]
[else
(make-ellipse (ellipse-height atomic-shape)
(ellipse-width atomic-shape)
(- new-angle 90)
(ellipse-mode atomic-shape)
(ellipse-color atomic-shape))]))])]
[(text? atomic-shape)
(error 'flip "cannot flip shapes that contain text")]
[(flip? atomic-shape)
(make-flip (not (flip-flipped? atomic-shape))
(flip-shape atomic-shape))]))
(define (flip-point point) (make-point (point-x point) (- (point-y point))))
(define (flip-points points) (map flip-point points))
;
;
;
; ;;;; ;; ;;
; ;;;; ;; ;;
; ;;;;;;; ;;;;;;; ;;;;; ;;;;; ;;;;;;; ;;;; ;;;;;;; ;;;;;;; ;;; ;;;;;
; ;;;;;;;; ;;;;;;;; ;;;;;; ;;;; ;;;;;; ;;;; ;;;;;;;;;;;;; ;;;;;;;; ;;;;;;;; ;;;;; ;;;;;;
; ;;;;;;;;; ;;;; ;;;; ;;;; ;;;;;;; ;;;; ;;;; ;;; ;;;; ;;;; ;;; ;;;; ;;;; ;; ;;;;
; ;;;; ;;;; ;;;;;;; ;;;; ;;;; ;;;; ;;;; ;;;; ;;; ;;;; ;;;;;;; ;;;;;;;; ;;;;;;; ;;;;
; ;;;;;;;;; ;; ;;;; ;;;; ;;;; ;;;;;;; ;;;; ;;;; ;;; ;;;; ;; ;;;; ;;;;;;; ;;;;; ;;;;
; ;;;;;;;; ;;;;;;;; ;;;;;; ;;;; ;;;;;; ;;;; ;;;; ;;; ;;;; ;;;;;;;; ; ;;;; ;;;;;; ;;;;;;
; ;;;;;;; ;; ;;;; ;;;;; ;;;; ;;;;; ;;;; ;;;; ;;; ;;;; ;; ;;;; ;;;;;;;; ;;;; ;;;;;
; ;;;;;;;;
; ;;;;;;
;
(define/chk (polygon posns mode color)
(check-mode/color-combination 'polygon 3 mode color)
(make-a-polygon (map (λ (p) (make-point (posn-x p) (posn-y p))) posns)
mode
color))
(define/chk (rectangle width height mode color)
(check-mode/color-combination 'rectangle 4 mode color)
(make-a-polygon (rectangle-points width height) mode color))
(define/chk (square side-length mode color)
(check-mode/color-combination 'square 3 mode color)
(make-a-polygon (rectangle-points side-length side-length) mode color))
(define/chk (empty-scene width height [color 'white])
(crop 0 0 width height
(overlay (rectangle width height 'outline (pen "black" 2 'solid 'round 'round))
(rectangle width height 'solid color))))
(define/chk (rhombus side-length angle mode color)
(check-mode/color-combination 'rhombus 3 mode color)
(let* ([left-corner (make-polar side-length (+ (* pi 1/2) (/ (degrees->radians angle) 2)))]
[right-corner (make-polar side-length (- (* pi 1/2) (/ (degrees->radians angle) 2)))]
[bottom-corner (+ left-corner right-corner)])
(make-a-polygon (list (make-point 0 0)
(make-point (real-part right-corner) (imag-part right-corner))
(make-point (real-part bottom-corner) (imag-part bottom-corner))
(make-point (real-part left-corner) (imag-part left-corner)))
mode
color)))
(define (rectangle-points width height [dx 0] [dy 0])
(list (make-point dx dy)
(make-point (+ dx width) dy)
(make-point (+ dx width) (+ height dy))
(make-point dx (+ dy height))))
(define/chk (line x1 y1 color)
(let-values ([(shape w h) (line-shape x1 y1 color)])
(make-image shape
(make-bb w h h)
#f)))
(define (line-shape x1 y1 color)
(let ([dx (- (min x1 0))]
[dy (- (min y1 0))]
[w (+ (abs x1) 1)]
[h (+ (abs y1) 1)])
(values (make-translate
dx dy
(make-line-segment (make-point 0 0)
(make-point x1 y1)
color))
w h)))
(define/chk (add-line image x1 y1 x2 y2 color)
(let* ([dx (abs (min 0 x1 x2))]
[dy (abs (min 0 y1 y2))]
[bottom (max (+ y1 dy)
(+ y2 dy)
(+ dy (get-bottom image)))]
[right (max (+ x1 dx)
(+ x2 dx)
(+ dx (get-right image)))]
[baseline (+ dy (get-baseline image))])
(make-image (make-translate
dx dy
(make-overlay
(make-line-segment (make-point x1 y1) (make-point x2 y2) color)
(image-shape image)))
(make-bb right bottom baseline)
#f
(send image get-pinhole))))
(define/chk (add-curve image x1 y1 angle1 pull1 x2 y2 angle2 pull2 color)
(let* ([dx (abs (min 0 x1 x2))]
[dy (abs (min 0 y1 y2))]
[bottom (max (+ y1 dy)
(+ y2 dy)
(+ dy (get-bottom image)))]
[right (max (+ x1 dx)
(+ x2 dx)
(+ dx (get-right image)))]
[baseline (+ dy (get-baseline image))])
(make-image (make-translate
dx dy
(make-overlay
(make-curve-segment (make-point x1 y1) angle1 pull1
(make-point x2 y2) angle2 pull2
color)
(image-shape image)))
(make-bb right bottom baseline)
#f
(send image get-pinhole))))
;; this is just so that 'text' objects can be sized.
(define text-sizing-bm (make-object bitmap-dc% (make-object bitmap% 1 1)))
(define/chk (text string font-size color)
(mk-text string font-size color #f 'swiss 'normal 'normal #f))
(define/chk (text/font string font-size color face family style weight underline)
(mk-text string font-size color face family style weight underline))
(define (mk-text str font-size color face family style weight underline)
(cond
[(<= (string-length str) 1)
(mk-single-text str font-size color face family style weight underline)]
[else
(let ([letters (string->list str)])
(beside/internal
'baseline
(mk-single-text (string (car letters)) font-size color face family style weight underline)
(map (λ (letter)
(mk-single-text (string letter) font-size color face family style weight underline))
(cdr letters))))]))
(define (mk-single-text letter font-size color face family style weight underline)
(let ([text (make-text letter 0 1 color font-size face family style weight underline)])
(let-values ([(w h d a) (send text-sizing-bm get-text-extent letter (text->font text))])
(make-image (make-translate (/ w 2) (/ h 2) text)
(make-bb w h (- h d))
#f))))
(define/chk (isosceles-triangle side-length angle mode color)
(check-mode/color-combination 'isosceles-triangle 4 mode color)
(let ([left-corner (make-polar side-length (+ (* pi 1/2) (/ (degrees->radians angle) 2)))]
[right-corner (make-polar side-length (- (* pi 1/2) (/ (degrees->radians angle) 2)))])
(make-a-polygon (list (make-point 0 0)
(make-point (real-part right-corner) (imag-part right-corner))
(make-point (real-part left-corner) (imag-part left-corner)))
mode
color)))
(define/chk (right-triangle side-length1 side-length2 mode color)
(check-mode/color-combination 'right-triangle 4 mode color)
(make-a-polygon (list (make-point 0 (- side-length2))
(make-point 0 0)
(make-point side-length1 0))
mode
color))
(define/chk (triangle side-length mode color)
(check-mode/color-combination 'triangle 3 mode color)
(make-polygon/star side-length 3 mode color values))
; excess : R+ R+ -> R
; compute the Euclidean excess
; Note: If the excess is 0, then C is 90 deg.
; If the excess is negative, then C is obtuse.
; If the excess is positive, then C is acuse.
(define (excess a b c)
(+ (sqr a) (sqr b) (- (sqr c))))
; polar->posn : R+ R -> (posn R R)
; return a position with x and y coordinates
(define (polar->posn radius angle)
(make-posn (* radius (cos angle))
(* radius (sin angle))))
; cos-rel : R R R -> R+
; return c^2 = a^2 + b^2 - 2ab cos(C)
(define (cos-rel a b C)
(+ (sqr a) (sqr b) (* -2 a b (cos C))))
; sin-rel : R R R -> R
; return the side b
(define (sin-rel A a B)
(/ (* a (sin B)) (sin A)))
; last-angle : R R -> R
; return pi-(A+B)
(define (last-angle A B)
(- pi A B))
(define (radians degree)
(* (/ degree 180.0) pi))
(define (triangle/sss side-a side-b side-c mode color)
(define (triangle-vertices/sss a b c)
(let ([A (acos (/ (excess b c a) (* 2 b c)))])
(list (make-posn 0 0)
(make-posn c 0)
(polar->posn b A))))
(check-dependencies 'triangle/sss
(and (>= (+ side-a side-b) side-c)
(>= (+ side-a side-c) side-b)
(>= (+ side-b side-c) side-a))
"the given side lengths will not form a triangle ~a, ~a, and, ~a."
side-a side-b side-c)
(polygon (triangle-vertices/sss side-a side-b side-c) mode color))
(define/chk (triangle/ass angle-a side-b side-c mode color)
(define (triangle-vertices/ass A b c)
(list (make-posn 0 0) (make-posn c 0) (polar->posn b A)))
(polygon (triangle-vertices/ass (radians angle-a) side-b side-c) mode color))
(define/chk (triangle/sas side-a angle-b side-c mode color)
(define (triangle-vertices/sas a B c)
(let ([b^2 (cos-rel a c B)])
(check-dependencies 'triangle/sas
"the given side, angle, and, side will not form a triangle ~a, ~a, and, ~a."
side-a angle-b side-c)
(let* ([b (sqrt b^2)]
[A (acos (/ (excess b c a) (* 2 b c)))])
(list (make-posn 0 0) (make-posn c 0) (polar->posn b A)))))
(polygon (triangle-vertices/sas side-a (radians angle-b) side-c) mode color))
(define/chk (triangle/ssa side-a side-b angle-c mode color)
(define (triangle-vertices/ssa a b C)
(let ([c^2 (cos-rel a b C)])
(check-dependencies 'triangle/ssa
(positive? c^2)
"the given side, side, and, angle will not form a triangle ~a, ~a, and, ~a."
side-a side-b angle-c)
(let*([c (sqrt c^2)]
[A (acos (/ (excess b c a) (* 2 b c)))])
(list (make-posn 0 0)
(make-posn c 0)
(polar->posn b A)))))
(polygon (triangle-vertices/ssa side-a side-b (radians angle-c)) mode color))
(define/chk (triangle/aas angle-a angle-b side-c mode color)
(define (triangle-vertices/aas A B c)
(let* ([C (last-angle A B)]
[b (sin-rel C c B)])
(list (make-posn 0 0) (make-posn c 0) (polar->posn b A))))
(polygon (triangle-vertices/aas (radians angle-a) (radians angle-b) side-c) mode color))
(define/chk (triangle/asa angle-a side-b angle-c mode color)
(define (triangle-vertices/asa A b C)
(let* ([B (last-angle A C)]
[c (sin-rel B b C)])
(list (make-posn 0 0) (make-posn c 0) (polar->posn b A))))
(polygon (triangle-vertices/asa (radians angle-a) side-b (radians angle-c)) mode color))
(define/chk (triangle/saa side-a angle-b angle-c mode color)
(define (triangle-vertices/saa a B C)
(let* ([A (last-angle B C)]
[b (sin-rel A a B)]
[c (sin-rel A a C)])
(list (make-posn 0 0)
(make-posn c 0)
(polar->posn b A))))
(polygon (triangle-vertices/saa side-a (radians angle-b) (radians angle-c)) mode color))
(define/chk (regular-polygon side-length side-count mode color)
(check-mode/color-combination 'regular-polygon 4 mode color)
(make-polygon/star side-length side-count mode color values))
(define/chk (star-polygon side-length side-count step-count mode color)
(check-mode/color-combination 'star-polygon 5 mode color)
(check-arg 'star-polygon
(step-count . < . side-count)
(format "number that is smaller than the side-count (~a)" side-count)
3
step-count)
(check-arg 'star-polygon
(= 1 (gcd side-count step-count))
(format "number that is relatively prime to the side-count (~a)" side-count)
3
step-count)
(make-polygon/star side-length side-count mode color (λ (l) (swizzle l step-count))))
(define/chk (star side-length mode color)
(check-mode/color-combination 'star 3 mode color)
(make-polygon/star side-length 5 mode color (λ (l) (swizzle l 2))))
(define (make-polygon/star side-length side-count mode color adjust)
(make-a-polygon (adjust (regular-polygon-points side-length side-count))
mode color))
(define/chk (radial-star point-count radius1 radius2 mode color)
(make-a-polygon (star-points radius1 radius2 point-count) mode color))
(define (star-points in-small-rad in-large-rad points)
(let* ([small-rad (- in-small-rad 1)]
[large-rad (- in-large-rad 1)]
[roff (floor (/ large-rad 2))])
(let loop ([i points])
(cond
[(zero? i) '()]
[else
(let* ([this-p (- i 1)]
[theta1 (* 2 pi (/ this-p points))]
[theta2 (* 2 pi (/ (- this-p 1/2) points))])
(let-values ([(x1 y1) (find-xy small-rad theta1)]
[(x2 y2) (find-xy large-rad theta2)])
(let ([p1 (make-point (+ large-rad x1)
(+ large-rad y1))]
[p2 (make-point (+ large-rad x2)
(+ large-rad y2))])
(list* p1 p2 (loop (- i 1))))))]))))
(define (find-xy radius theta)
(values (* radius (cos theta))
(* radius (sin theta))))
(define (make-a-polygon points mode color)
(let* ([poly (make-polygon points mode color)]
[ltrb (simple-bb poly)]
[l (ltrb-left ltrb)]
[t (ltrb-top ltrb)]
[r (ltrb-right ltrb)]
[b (ltrb-bottom ltrb)])
(make-image (make-translate (- l) (- t) poly)
(make-bb (- r l) (- b t) (- b t))
#f)))
(define (gcd a b)
(cond
[(zero? b) a]
[else (gcd b (modulo a b))]))
;; swizzle : (listof X)[odd-length] -> (listof X)
;; returns a list with the same elements,
;; but reordered according to the step. Eg, if the step
;; is 2, we get the even elements and then the odd ones.
(define (swizzle l step)
(let ([v (list->vector l)])
(let loop ([i 0])
(cond
[(= i (vector-length v)) '()]
[else
(cons (vector-ref v (modulo (* i step) (vector-length v)))
(loop (+ i 1)))]))))
;; regular-polygon-points : number number -> (listof point)
(define (regular-polygon-points side-length side-count)
(let loop ([p (make-rectangular 0 0)]
[i 0])
(cond
[(= i side-count) '()]
[else (cons (make-point (real-part p) (imag-part p))
(loop (+ p (make-polar side-length
(* -1 (* 2 pi) (/ i side-count))))
(+ i 1)))])))
(define/chk (ellipse width height mode color)
(check-mode/color-combination 'ellipse 4 mode color)
(make-image (make-translate (/ width 2) (/ height 2)
(make-ellipse width height
0
mode
color))
(make-bb width height height)
#f))
(define/chk (circle radius mode color)
(check-mode/color-combination 'circle 3 mode color)
(let ([w/h (* 2 radius)])
(make-image (make-translate radius radius (make-ellipse w/h w/h 0 mode color))
(make-bb w/h w/h w/h)
#f)))
(define empty-image (rectangle 0 0 'solid 'black))
(define/chk (image-width image) (bb-select/round/exact bb-right image))
(define/chk (image-height image) (bb-select/round/exact bb-bottom image))
(define/chk (image-baseline image) (bb-select/round/exact bb-baseline image))
(define (bb-select/round/exact select image) (inexact->exact (round (select (send image get-bb)))))
(define-syntax (bitmap stx)
(syntax-case stx ()
[(_ arg)
(let* ([arg (syntax->datum #'arg)]
[path/lst
(cond
[(and (pair? arg)
(eq? (car arg) 'planet))
(raise-syntax-error 'bitmap "planet paths not yet supported" stx)]
[(symbol? arg)
(let ([pieces (regexp-split #rx"/" (symbol->string arg))])
(cond
[(null? pieces)
(raise-syntax-error 'bitmap "expected a path with a / in it" stx)]
[else
(define fn (last pieces))
(define colls (reverse (cdr (reverse pieces))))
(define candidate
(apply collection-file-path fn colls
#:fail
(λ (msg) (raise-syntax-error 'bitmap msg stx))))
(unless (file-exists? candidate)
(raise-syntax-error 'bitmap
(format "could not find ~s, expected it to be in ~a"
arg candidate)
stx))
(cons fn colls)]))]
[(string? arg)
(path->complete-path
arg
(or (current-load-relative-directory)
(current-directory)))]
[else (raise-syntax-error
'bitmap
"expected the argument to specify a local path (via a string) or a module path (e.g. `icons/b-run.png')"
stx)])])
#`(bitmap/proc '#,path/lst))]))
(define (bitmap/proc arg)
(define pth (if (path? arg)
arg
(apply collection-file-path arg
#:fail
(λ (msg) (error 'bitmap msg)))))
(when (and (path? pth)
(not (file-exists? pth)))
(error 'bitmap "could not find the file ~a" (path->string pth)))
;; the rotate does a coercion to a 2htdp/image image
(rotate 0 (make-object image-snip% (make-object bitmap% pth 'unknown/alpha))))
(define/chk (bitmap/url string)
;; the rotate does a coercion to a 2htdp/image image
(rotate
0
(call/input-url (string->url string)
get-pure-port
(λ (port)
(make-object bitmap% port 'unknown #f #t)))))
(define/chk (bitmap/file filename)
(unless (file-exists? filename)
(error 'bitmap/file
"could not find the file ~a"
filename))
(rotate
0
(read-bitmap filename)))
(define/chk (image->color-list image)
(let* ([w (image-width image)]
[h (image-height image)]
[bm (make-bitmap w h)]
[bdc (make-object bitmap-dc% bm)]
[c (make-object color%)]
[bytes (make-bytes (* w h 4))])
(send bdc erase)
(render-image image bdc 0 0)
(send bdc get-argb-pixels 0 0 w h bytes)
(for/list ([i (in-range 0 (* w h 4) 4)])
(color (bytes-ref bytes (+ i 1))
(bytes-ref bytes (+ i 2))
(bytes-ref bytes (+ i 3))
(bytes-ref bytes i)))))
(define/chk (color-list->bitmap color-list width height)
(check-dependencies 'color-list->bitmap
(= (* width height) (length color-list))
"the length of the color list to match the product of the width and the height, but the list has ~a elements and the width and height are ~a and ~a respectively"
(length color-list) width height)
(let* ([bmp (make-bitmap width height)]
[bytes (make-bytes (* width height 4) 0)]
[o (make-object color%)])
(for ([c (in-list color-list)]
[i (in-naturals)])
(define j (* i 4))
(cond
[(color? c)
(bytes-set! bytes j (color-alpha c))
(bytes-set! bytes (+ j 1) (color-red c))
(bytes-set! bytes (+ j 2) (color-green c))
(bytes-set! bytes (+ j 3) (color-blue c))]
[else
(let* ([str (if (string? c) c (symbol->string c))]
[clr (or (send the-color-database find-color str)
(send the-color-database find-color "black"))])
(bytes-set! bytes j 255) ;; this should probably (send clr alpha) when that's possible
(bytes-set! bytes (+ j 1) (send clr red))
(bytes-set! bytes (+ j 2) (send clr green))
(bytes-set! bytes (+ j 3) (send clr blue)))]))
(send bmp set-argb-pixels 0 0 width height bytes)
(bitmap->image bmp)))
(define build-color/make-color
(let ([orig-make-color make-color])
(define/chk make-color
(case-lambda
[(int0-255-1 int0-255-2 int0-255-3)
(orig-make-color int0-255-1 int0-255-2 int0-255-3)]
[(int0-255-1 int0-255-2 int0-255-3 int0-255-4)
(orig-make-color int0-255-1 int0-255-2 int0-255-3 int0-255-4)]))
make-color))
(define/chk (pinhole-x image) (let ([ph (send image get-pinhole)]) (and ph (point-x ph))))
(define/chk (pinhole-y image) (let ([ph (send image get-pinhole)]) (and ph (point-y ph))))
(define/chk (put-pinhole x1 y1 image) (make-image (image-shape image) (image-bb image) (image-normalized? image) (make-point x1 y1)))
(define/chk (center-pinhole image)
(let ([bb (send image get-bb)])
(make-image (image-shape image)
(image-bb image)
(image-normalized? image)
(make-point (/ (bb-right bb) 2)
(/ (bb-baseline bb) 2)))))
(define/chk (clear-pinhole image) (make-image (image-shape image) (image-bb image) (image-normalized? image) #f))
(define build-color/color
(let ([orig-make-color make-color])
(define/chk color
(case-lambda
[(int0-255-1 int0-255-2 int0-255-3)
(orig-make-color int0-255-1 int0-255-2 int0-255-3)]
[(int0-255-1 int0-255-2 int0-255-3 int0-255-4)
(orig-make-color int0-255-1 int0-255-2 int0-255-3 int0-255-4)]))
color))
(define build-pen/make-pen
(let ([orig-make-pen make-pen])
(define/chk (make-pen color int-0-255 pen-style pen-cap pen-join)
(orig-make-pen color int-0-255 pen-style pen-cap pen-join))
make-pen))
(define build-pen/pen
(let ([orig-make-pen make-pen])
(define/chk (pen color int-0-255 pen-style pen-cap pen-join)
(orig-make-pen color int-0-255 pen-style pen-cap pen-join))
pen))
(define/chk freeze
(case-lambda
[(image) (freeze/internal 0 0 (image-width image) (image-height image) image)]
[(width height image) (freeze/internal 0 0 width height image)]
[(x y width height image) (freeze/internal x y width height image)]))
(define (freeze/internal x y w h image)
(define bm (make-bitmap w h))
(define bdc (make-object bitmap-dc% bm))
(render-image image bdc (- x) (- y))
(send bdc set-bitmap #f)
(to-img bm))
(provide overlay
overlay/align
overlay/offset
overlay/align/offset
overlay/xy
underlay
underlay/align
underlay/align/offset
underlay/offset
underlay/xy
beside
beside/align
above
above/align
rotate
crop
flip-vertical
flip-horizontal
frame
place-image
place-image/align
save-image
save-svg-image
bring-between
scale
scale/xy
image-width
image-height
image-baseline
circle
ellipse
rectangle
empty-scene
square
rhombus
empty-image
polygon
regular-polygon
triangle
triangle/sss
triangle/ssa
triangle/sas
triangle/ass
triangle/aas
triangle/asa
triangle/saa
isosceles-triangle
right-triangle
star
star-polygon
radial-star
line
add-line
add-curve
scene+line
scene+curve
text
text/font
image->color-list
color-list->bitmap
bitmap
bitmap/url
bitmap/file
swizzle
rotate-xy
put-pinhole
pinhole-x
pinhole-y
clear-pinhole
center-pinhole
overlay/pinhole
underlay/pinhole
build-color/make-color
build-color/color
build-pen/make-pen
build-pen/pen
freeze
render-image)
(provide/contract
[np-atomic-bb (-> np-atomic-shape? (values real? real? real? real?))]
[center-point (-> np-atomic-shape? number?)])