Usually you adjust the drawing context's scale. Something like (untested):
(define bm (read-bitmap ...)) (define dc (send image-box get-dc)) (define t (send dc get-transformation)) ; save old scale (send dc scale (/ (send image-box get-width) (send bm get-width)) (/ (send image-box get-height) (send bm get-height))) (send dc draw-bitmap bm 0 0) (send dc set-transformation t) ; restore old scale If you want to create a new bitmap with the exact size you want, then you create a new bitmap and use the same strategy: (define new-bm (make-bitmap w h)) (define dc (send new-bm get-dc)) ; same as above Does that help? Dave On Sat, Aug 11, 2018 at 9:48 PM, <silverfire...@gmail.com> wrote: > (define image-box > (new canvas% [parent frame] > [min-width 300] > [min-height 300])) > > I'm still trying to figure out how the racket/gui library works but I'm > having some difficulty understanding how to have an image fill a canvas. > > I'd like for instance to have a canvas in my gui that is 300x300 and have > any image I load resized to fit those dimensions. > > (send (send image-box get-dc) > draw-bitmap > (read-bitmap (string->path (send list-box get-string > select))) > 0 0)))))) > > Here I have some quickly thrown together code for selecting a list of > pathnames to images from a list-box. The images are all different sizes and > usually end up exceeding the canvas size. > > I've looked around the documentation, especially in the racket/draw module > but I can't find anything beyond a "scale" which doesn't really seem all > that helpful. If anyone knows how to change images to certain sizes that'd > be helpful. I tried looking at racket/pict too but that doesn't seem to > have anyway to absolutely set a image's dimensions. > > Thanks! > > -- > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
