[racket] plot pixel position

Aha - clever.  Thanks!

On 04/16/2014 12:09 PM, Neil Toronto wrote:
> On 04/15/2014 12:59 PM, David Vanderson wrote:
>>
>> Is there a way to access area's plot->dc?  For this example I wanted to
>> ask if the mouse was within 2 pixels of any point.
>
> There's unfortunately not. But if your plots don't have axis 
> transforms (i.e. have the identity transform), it's a linear function, 
> so you can apply dc->plot to two points and derive it from the return 
> values.
>
> Neil ⊥
>
>