Wow, that's really fast! Thanks for looking into this. Unfortunately, text-outline seems to garble some glyphs. Am I doing something wrong? As of commit e12bf33..., the attached code produces this ... output, which looks more like an impersonation of my handwriting than a text path:
http://img580.imageshack.us/img580/9038/garbled.jpg This is on Arch Linux, cairo 1.10.2-2, pango 1.29.4-1. Even constructing a path of just a single character (such as "r" or "e" on my system) exhibits this behavior for me. Let me know if there's anything I can do to help. ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; (require slideshow/pict racket/draw) (dc (λ (dc x y) (define r (new region%)) (let ([p (new dc-path%)]) (send p text-outline (make-object font% 35 'default) "Hello world" x y) (send r set-path p)) (send dc set-clipping-region r) (send dc set-brush "black" 'solid) (send dc draw-rectangle 0 0 500 200)) 500 200) 7 hours ago, Matthew Flatt wrote: > I guess I've been waiting for a reason to sort out text paths. The > `dc-path%' class now has a `text-outline' method (as of the latest in > the git repo). > > At Sun, 25 Dec 2011 00:00:44 -0700, Michael W wrote: > > Merry Christmas, Racketeers! > > > > Is there an easy way to draw text to a bitmap% with a gradient? > > > > I briefly looked into adding linear-gradient% and > > radial-gradient% support to slideshow/pict but unfortunately we > > can't draw text using an arbitrary brush% as the draw-text method > > of dc% ignores that. > > > > My current trick is to draw the gradient to one bitmap, draw the > > text to another bitmap, and then draw the first bitmap to a third > > bitmap while copying the mask of the second. Is there a better > > way? > > > > ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; > > #lang racket > > (require slideshow/pict > > racket/draw) > > > > (define (compose-picts base alpha) > > ;; Return a bitmap% with the colors of base but the alpha of alpha. > > (define-values (w h) > > (values (inexact->exact (ceiling (pict-width base))) > > (inexact->exact (ceiling (pict-height base))))) > > (define-values (base-bitmap alpha-bitmap final-bitmap) > > (values (make-bitmap w h) > > (make-bitmap w h) > > (make-bitmap w h))) > > (define-values (base-dc alpha-dc final-dc) > > (apply values (map (λ(bm) (new bitmap-dc% [bitmap bm])) > > (list base-bitmap alpha-bitmap final-bitmap)))) > > (send base-dc set-smoothing 'aligned) > > (draw-pict base base-dc 0 0) > > (send alpha-dc set-smoothing 'aligned) > > (draw-pict alpha alpha-dc 0 0) > > (send final-dc draw-bitmap base-bitmap 0 0 'solid #f alpha-bitmap) > > final-bitmap) > > > > ;; The text to render > > (define my-text > > (scale (text "Hello World") 4)) > > > > ;; The linear-gradient% to render > > (define gradient > > (new linear-gradient% [x0 0] [y0 0] [x1 0] [y1 (pict-height my-text)] > > [stops (list (list 0.0 (make-object color% 0 0 0)) > > (list 1.0 (make-object color% 255 0 0)))])) > > > > ;; A box containing the gradient > > (define gradient-box > > (dc > > (λ(dc w h) > > (send dc set-pen (make-object pen% "white" 1 'transparent)) > > (send dc set-brush (new brush% [gradient gradient])) > > (send dc draw-rectangle > > 0 0 (pict-width my-text) (pict-height my-text))) > > (pict-width my-text) (pict-height my-text))) > > > > ;; The final result: Gradient-filled text! > > (bitmap (compose-picts gradient-box my-text)) > > > > -- > > Heave ho, > > _mike -- For the Future! _mike ____________________ Racket Users list: http://lists.racket-lang.org/users
