[plt-scheme] 2htdp/image questions

From: Robby Findler (robby at eecs.northwestern.edu)
Date: Sun Apr 18 12:39:50 EDT 2010

I'm sorry: I've mentioned this before but I can see how you might
thing that I'm contradicting myself now. Those particular functions
are in the plan (if not already there; I forget exactly what  I've
finished). The new library however is much more suited to shape-based
manipulations of images.

And, of course, the old library won't go away so you can feel free to
convert (or not) as your needs and course preparation dictate.

Robby

On Sunday, April 18, 2010, Jordan Johnson <jmj at fellowhuman.com> wrote:
> Why not (since it's already mostly written--right?) have a distinct bitmap image type and bitmap library that provides the color-list and alpha-color-list functionality of the old htdp/image lib?  (i.e., just rename the types of data in the old library to make it obvious that they are distinct from the 2htdp-style images)  My students thought the color-list exercises this year were really neat, so it would be nice to provide a way to continue doing them, tho in the long run I'd think it's best not to have two image libs so similarly named.
>
> Best,
> Jordan
>
> On Apr 18, 2010, at 7:51 AM, Robby Findler <robby at eecs.northwestern.edu> wrote:
>
>
> On Sun, Apr 18, 2010 at 9:27 AM, Stephen Bloch <sbloch at adelphi.edu> wrote:
>
> BTW, if two images both already had cached bitmaps, would it be faster or
> slower to compare the bitmaps than to do the usual tree-traversal equality?
>
>
> Much slower in the common case.
>
>
>  I guess that would depend on the size of the bitmaps, and the complexity of
> the tree....
>
>
> Yes, of course, in general.
>
> But I really believe that if you want to be writing such functions you
> don't want 2htdp/image. You want a completely different
> representation.
>
> Robby
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