suzanne.soy/racket
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

dc<%>: fix baseline for slow-path non-combined text drawing

Browse Source 
For example, fix baseline when drawing "a\u2144" with the
default fonr under Windows, where #\u2144 is subtituted from
another font.
This commit is contained in:
Matthew Flatt 2013-02-04 18:58:00 -07:00
parent 442f6eaaae
commit c17c7cd1b0
1 changed files with 62 additions and 46 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

108
collects/racket/draw/private/dc.rkt
View File

@ -1501,52 +1501,68 @@
(free log-clusters)
#t)))))
;; We use the slower, per-layout way:
(for/fold ([w 0.0][h 0.0][d 0.0][a 0.0])
([ch (in-string s)])
(let ([layout (vector-ref (hash-ref layouts (char->integer ch)) 0)])
(let-values ([(lw lh ld la flh)
(let ([v (and cache (hash-ref cache (char->integer ch) #f))])
(if v
;; Used cached size:
(values (vector-ref v 0)
(vector-ref v 1)
(vector-ref v 2)
(vector-ref v 3)
(vector-ref v 6))
;; Query and record size:
(let ([logical (make-PangoRectangle 0 0 0 0)])
(pango_layout_get_extents layout #f logical)
(let ([baseline (pango_layout_get_baseline layout)]
[orig-h (PangoRectangle-height logical)])
(let ([lw (force-hinting
(/ (PangoRectangle-width logical)
(exact->inexact PANGO_SCALE)))]
[flh (/ orig-h (exact->inexact PANGO_SCALE))]
[ld (exact->inexact (/ (- orig-h baseline) (exact->inexact PANGO_SCALE)))]
[la 0.0])
(let ([lh (ceiling flh)])
(when cache
(hash-set! cache (char->integer ch)
(vector lw lh ld la
;; baseline in Pango units; for fast path
baseline
;; rounded width in Pango units; for fast path
(inexact->exact
(floor (* lw (->fl PANGO_SCALE))))
;; unrounded height, for slow-path alignment
flh)))
(values lw lh ld la flh)))))))])
(when draw-mode
(cairo_move_to cr
(text-align-x/delta (+ x w) 0)
(let ([bl (- flh ld)])
(text-align-y/delta (+ y bl) 0)))
;; Here's the draw command, which uses most of the time in this mode:
(let ([line (pango_layout_get_line_readonly layout 0)])
(if (eq? draw-mode 'draw)
(pango_cairo_show_layout_line cr line)
(pango_cairo_layout_line_path cr line))))
(values (if blank? 0.0 (+ w lw)) (max h lh) (max d ld) (max a la))))))
(let* ([query-and-cache
(lambda (ch layout)
(let ([logical (make-PangoRectangle 0 0 0 0)])
(pango_layout_get_extents layout #f logical)
(let ([baseline (pango_layout_get_baseline layout)]
[orig-h (PangoRectangle-height logical)])
(let ([lw (force-hinting
(/ (PangoRectangle-width logical)
(exact->inexact PANGO_SCALE)))]
[flh (/ orig-h (exact->inexact PANGO_SCALE))]
[ld (exact->inexact (/ (- orig-h baseline) (exact->inexact PANGO_SCALE)))]
[la 0.0])
(let ([lh (ceiling flh)])
(when cache
(hash-set! cache (char->integer ch)
(vector lw lh ld la
;; baseline in Pango units; for fast path
baseline
;; rounded width in Pango units; for fast path
(inexact->exact
(floor (* lw (->fl PANGO_SCALE))))
;; unrounded height, for slow-path alignment
flh)))
(values lw lh ld la flh))))))]
[bl
(if draw-mode
;; For drawing, need to compute baseline first:
(for/fold ([h 0.0]) ([ch (in-string s)])
(let ([layout (vector-ref (hash-ref layouts (char->integer ch)) 0)])
(max (let ([v (and cache (hash-ref cache (char->integer ch) #f))])
(if v
;; Used cached size:
(- (vector-ref v 6) (vector-ref v 2))
;; Query and record size:
(let-values ([(lw lh ld la flh) (query-and-cache ch layout)])
(- flh ld))))
h)))
0.0)])
(for/fold ([w 0.0] [h 0.0] [d 0.0] [a 0.0])
([ch (in-string s)])
(let ([layout (vector-ref (hash-ref layouts (char->integer ch)) 0)])
(let-values ([(lw lh ld la flh)
(let ([v (and cache (hash-ref cache (char->integer ch) #f))])
(if v
;; Used cached size:
(values (vector-ref v 0)
(vector-ref v 1)
(vector-ref v 2)
(vector-ref v 3)
(vector-ref v 6))
;; Query and record size:
(query-and-cache ch layout)))])
(when draw-mode
(cairo_move_to cr
(text-align-x/delta (+ x w) 0)
(text-align-y/delta (+ y bl) 0))
;; Here's the draw command, which uses most of the time in this mode:
(let ([line (pango_layout_get_line_readonly layout 0)])
(if (eq? draw-mode 'draw)
(pango_cairo_show_layout_line cr line)
(pango_cairo_layout_line_path cr line))))
(values (if blank? 0.0 (+ w lw)) (max h lh) (max d ld) (max a la)))))))
(when rotate? (cairo_restore cr))))))))
(define/private (extract-only-run layout vec)