[racket] 2htdp/image: Silent cropping?

From: Jordan Johnson (jmj at fellowhuman.com)
Date: Sat Jan 24 13:56:45 EST 2015

I'd be fine with that solution.

Best,
Jordan

> On Jan 24, 2015, at 7:10 AM, Matthias Felleisen <matthias at ccs.neu.edu> wrote:
> 
> 
> I prefer leaving it alone but documenting the limitation -- Matthias
> 
> 
> 
> 
> 
>> On Jan 23, 2015, at 9:30 PM, Robby Findler wrote:
>> 
>> Maybe the right thing to do is leave the arbitrary limit in there, but
>> make it based on the area, not based independently on the width and
>> height. Then your example would work, but (ellipse 5050 5050)
>> wouldn't.
>> 
>> Robby
>> 
>> 
>> On Fri, Jan 23, 2015 at 8:22 PM, Robby Findler
>> <robby at eecs.northwestern.edu> wrote:
>>> Yes, 2htdp/image truncates the images to 5000x5000 when building a bitmap.
>>> 
>>> I did that in response to this PR:
>>> 
>>> http://bugs.racket-lang.org/query/?debug=&database=default&cmd=view+audit-trail&cmd=view&pr=12277
>>> 
>>> but I'm not sure what's the right answer here. I'm hesitant to add
>>> errors but maybe that's the best thing.
>>> 
>>> Robby
>>> 
>>> 
>>>> On Fri, Jan 23, 2015 at 7:52 PM, Jordan Johnson <jmj at fellowhuman.com> wrote:
>>>> Hi all,
>>>> 
>>>> A student of mine noticed yesterday that part of an image was getting
>>>> truncated. Some further experimentation in BSL yielded this example:
>>>> 
>>>> (ellipse 5050 100 'solid 'blue) ; => image with 50 pixels missing at right
>>>> end
>>>> (ellipse 100 5050 'solid 'blue) ; => image with 50 pixels missing at bottom
>>>> 
>>>> For both images, the image-{width,height} functions produce 100 and 5050;
>>>> the library simply doesn't draw the entire ellipse, although click-and-drag
>>>> highlighting does show the image as having 50 extra blank pixels at the end.
>>>> 
>>>> I can't find documentation of the size limits. Is this intended behavior? If
>>>> so, an error might be more student-friendly.
>>>> 
>>>> Cheers,
>>>> Jordan
>>>> 
>>>> 
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> 


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