Although your attached bitmap is in 1-bit format, it has a color palette in the PNG file format, as opposed to being identified as "grayscale" at that level.
I couldn't figure out how to get Preview or GIMP to re-save the PNG as grayscale. Meanwhile, there we bugs in `racket/draw' for monochrome PNG reading and writing; I'll soon push repairs. After the repairs, (define bm (make-object bitmap% 16 16 #t #f)) (define bm2 (read-bitmap "test-icon.png")) (send (send bm make-dc) draw-bitmap bm2 0 0) (send bm save-file "t2.png" 'png) converts "test-icon.png" to a grayscale monochrome "t2.png", and that file works for a cursor. At Thu, 11 Oct 2012 15:18:13 -0600, Kieron Hardy wrote: > Hi all, > > I'm having trouble loading a 16x16 monochrome image such that it can be > used as a cursor%. > > The documentation states that using load-file with a kind of 'bmp always > loads as colour, but it would be nice to have a new kind (perhaps > 'monochrome-bmp) that loads monochrome images to monochrome bitmaps. > > The documentation also states that a monochrome png will load as a > monochrome bitmap%, but it seems to always load as colour (changing the bit > depth from 1 to 32 during the load-file, regardless of the value specified > for kind). Perhaps there's something wrong with my image file (attached) > but gimp and Windows both show a 1-bit colour depth. > > I have a work-around, in that converting the image to xbm seems to work. > But I'm still interested to know what I was doing wrong, anyone have any > ideas? > > Cheers, > > Kieron. > > **** > > #lang racket > > (require racket/gui) > > (define bm (make-object bitmap% 16 16 #t #f)) > (printf " ~a ~a ~a ~a~n" (send bm get-width) (send bm get-height) (send bm > get-depth) (send bm is-color?)) > > (send bm load-file "test-icon.png" 'png #f #t) > ;(send bm load-file "test-icon.xbm" 'xbm #f #t) > (printf " ~a ~a ~a ~a~n" (send bm get-width) (send bm get-height) (send bm > get-depth) (send bm is-color?)) > > (define cursor (make-object cursor% bm bm 0 0)) ____________________ Racket Users list: http://lists.racket-lang.org/users
