Oh, now that I re-read that code I see a bug: it needs to set the pen back. So the last line of the procedure passed to dc should be:
(send dc set-pen pen) Robby On Sat, May 26, 2012 at 11:03 AM, Jens Axel Søgaard <[email protected]> wrote: > 2012/5/26 Robby Findler <[email protected]>: >> Oh, in that case, you could do this: >> >> (hc-append (blank 1 0) (hline (- w 1) 1)) > > Thanks! > >> If you don't want the rounded edges, you'd have to do something like this: >> >> (define (fraction p q) >> (define w (max (pict-width p) (pict-width q))) >> (vc-append p (vc-append (blank 0 2) (butt-hline w)) q)) >> >> (require racket/gui/base) >> (define (butt-hline w) >> (dc >> (λ (dc dx dy) >> (define pen (send dc get-pen)) >> (send dc set-pen (send the-pen-list find-or-create-pen >> (send pen get-color) >> (send pen get-width) >> 'solid >> 'butt)) >> (send dc draw-line dx dy (+ dx w) dy)) >> w 1)) > > I think I can use this technique to make roots. > And to make a proper "vector arrow". > > Thanks, > Jens Axel ____________________ Racket Users list: http://lists.racket-lang.org/users
