[plt-scheme] 2htdp/image Images in Slideshow

This appears to be a bug in the handling of 'smoothed drawing mode.
Below is an example program that illustrates the bug.

#lang racket/gui

(define (draw c dc)
  (send dc set-origin 159.0 -1.0)
  (let ([new-region (new region% [dc dc])]
        [path (new dc-path%)])
    (send path move-to 0 0)
    (send path line-to 100 0)
    (send path line-to 100 100)
    (send path line-to 0 100)
    (send new-region set-path path 462 334)
    (send dc set-clipping-region new-region)
    (send dc draw-rectangle 462 334 100 100)
    (let* ([path (new dc-path%)]
           [ew 20]
           [eh 20]
           [θ 0]
           [color "red"]
           [mode 'solid])
      (send path ellipse 0 0 20 20)
      (send dc set-smoothing 'smoothed) ;;; remove this line and it draws
      (send dc draw-path path 512 384))))

(define f2 (new frame% [label ""]))
(define c2 (new canvas%
                [parent f2]
                [min-width 1000]
                [min-height 500]
                [paint-callback draw]))
(send f2 show #t)


On Fri, May 28, 2010 at 3:21 PM, Nadeem Abdul Hamid <nadeem at acm.org> wrote:
> This image->pict function doesn't seem to work with place-image when embedded in a slide. When I use it in the interactions pane, it does produce the expected pict, but when it renders the slide below, all I get is an empty scene....
>
>
> #lang slideshow
>
> (require (prefix-in im: 2htdp/image))
> (require mrlib/image-core)
>
> (define (image->pict img)
>  (dc (λ (dc dx dy) (render-image img dc dx dy))
>     (im:image-width img)
>     (im:image-height img)))
>
> (slide
>  (image->pict (im:place-image
>               (im:circle 10 "solid" "red") 50 50
>               (im:empty-scene 100 100))))
>
>
>
>
>
>
> On May 25, 2010, at 4:59 PM, Robby Findler wrote:
>
>> You can do this:
>>
>> #lang scheme
>> (require slideshow slideshow/code)
>>
>> (require (prefix-in im: 2htdp/image)
>>         mrlib/image-core)
>>
>> (define (image->pict img)
>>  (dc (λ (dc dx dy) (render-image img dc dx dy))
>>      (im:image-width img)
>>      (im:image-height img)))
>>
>> (slide
>> (hbl-append (code (rectangle 15 25 "solid" "blue"))
>>             (t "=>")
>>             (image->pict (im:rectangle 15 25 "solid" "blue"))))
>>
>> I see that render-image isn't documented, tho. Apologies for that.
>>
>> Robby
>>
>> On Tue, May 25, 2010 at 2:45 PM, Nadeem Abdul Hamid <nadeem at acm.org> wrote:
>>>
>>> How can one embed images generated using 2htdp/image into a slideshow? Is there an easy tweak to make something like this work:
>>>
>>> (require (prefix-in im: 2htdp/image))
>>> (slide
>>>  (hbl-append (code (rectangle 15 25 "solid" "blue")) (t "=>")  (im:rectangle 15 25 "solid" "blue"))
>>>  )
>>>
>>> --- nadeem
>>>
>>>
>>> _________________________________________________
>>>  For list-related administrative tasks:
>>>  http://list.cs.brown.edu/mailman/listinfo/plt-scheme
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>
>