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, <[email protected]> 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 [email protected]. > 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 [email protected]. For more options, visit https://groups.google.com/d/optout.
