methodize afm-font

main
Matthew Butterick 6 years ago
parent a5c00ea2aa
commit 30220b42d2

@ -1,88 +1,92 @@
#lang at-exp racket/base
#lang racket/base
(require
racket/class
racket/file
racket/match
racket/string
racket/contract
racket/list
sugar/unstable/class
sugar/unstable/js
sugar/unstable/dict)
(provide AFMFont AFMFont-open)
(define (AFMFont-open filename)
(make-object AFMFont (open-input-file filename)))
(define AFMFont
(class object%
(super-new)
(init-field contents)
(field [attributes (mhasheq)]
[glyphWidths (mhash)]
(field [@attributes (mhasheq)]
[@glyph-widths (mhash)]
[boundingBoxes (mhash)]
[kernPairs (mhash)])
(parse this)
[@kern-pairs (mhash)])
(for/fold ([last-section #f])
([line (in-lines contents)])
(define current-section (cond
[(regexp-match #px"(?<=^Start)\\w+" line) => car]
[(regexp-match #px"(?<=^End)\\w+" line) #f]
[else last-section]))
(case current-section
[("FontMetrics")
;; line looks like this:
;; FontName Helvetica
;; `key space value`. Possibly multiple lines with same key.
(match-define (list _ key value) (regexp-match #px"^(\\w+)\\s+(.*)" line))
(hash-update! @attributes (string->symbol key)
(λ (v) (if (eq? v 'init-val)
value
(append (if (pair? v) v (list v)) (list value))))
'init-val)]
[("CharMetrics")
;; line looks like this:
;; C 33 ; WX 278 ; N exclam ; B 90 0 187 718 ;
;; need to retrieve N and WX fields
(when (regexp-match #px"^CH?\\s" line)
(define assocs (for/list ([field (in-list (string-split line #px"\\s*;\\s*"))])
(string-split field " ")))
(define name (second (assoc "N" assocs)))
(define width (string->number (second (assoc "WX" assocs))))
(hash-set! @glyph-widths name width))]
[("KernPairs")
(when (string-prefix? line "KPX")
(match-define (list _ left right val) (string-split line))
(hash-set! @kern-pairs (make-kern-table-key left right) (string->number val)))])
current-section)
(field [charWidths (for/list ([i (in-range 256)])
(hash-ref glyphWidths (vector-ref characters i) #f))])
(field [bbox (for/list ([attr (in-list (string-split (hash-ref attributes 'FontBBox)))])
(or (string->number attr) 0))])
(field [ascender (string->number (or (hash-ref attributes 'Ascender #f) "0"))])
(field [descender (string->number (or (hash-ref attributes 'Descender #f) "0"))])
(field [line-gap (- (- (list-ref bbox 3) (list-ref bbox 1)) (- ascender descender))])
(as-methods
parse
encodeText
glyphsForString
characterToGlyph
advancesForGlyphs
widthOfGlyph
getKernPair)
))
(define/contract (AFMFont-open filename)
(path-string? . -> . (is-a?/c AFMFont))
(make-object AFMFont (file->string filename)))
(define/contract (parse this)
(->m void?)
(for*/fold ([last-section #f])
([line (in-list (string-split (· this contents) "\n"))])
(define current-section (cond
[(regexp-match #px"^Start(\\w+)" line) => (λ (match) (cadr match))]
[(regexp-match #px"^End(\\w+)" line) #f]
[else last-section]))
(case current-section
[("FontMetrics")
;; line looks like this:
;; FontName Helvetica
;; `key space value`. Possibly multiple lines with same key.
(match-define (list _ key value) (regexp-match #px"^(\\w+)\\s+(.*)" line))
(hash-update! (· this attributes) (string->symbol key)
(λ (v) (if (eq? v 'init-val)
value
(append (if (pair? v) v (list v)) (list value))))
'init-val)]
[("CharMetrics")
;; line looks like this:
;; C 33 ; WX 278 ; N exclam ; B 90 0 187 718 ;
;; need to retrieve N and WX fields
(when (regexp-match #px"^CH?\\s" line)
(define assocs (for/list ([field (in-list (string-split line #px"\\s*;\\s*"))])
(string-split field " ")))
(define name (second (assoc "N" assocs)))
(define width (string->number (second (assoc "WX" assocs))))
(hash-set! (· this glyphWidths) name width))]
[("KernPairs")
(when (string-prefix? line "KPX")
(match-define (list _ left right val) (string-split line))
(hash-set! (· this kernPairs) (make-kern-table-key left right) (string->number val)))])
current-section)
(void))
(define (make-kern-table-key left right)
(cons left right))
(hash-ref @glyph-widths (vector-ref characters i) #f))])
(field [(@bbox bbox) (for/list ([attr (in-list (string-split (hash-ref @attributes 'FontBBox)))])
(or (string->number attr) 0))])
(field [(@ascender ascender) (string->number (or (hash-ref @attributes 'Ascender #f) "0"))])
(field [(@descender descender) (string->number (or (hash-ref @attributes 'Descender #f) "0"))])
(field [line-gap (- (list-ref @bbox 3) (list-ref @bbox 1) @ascender @descender)])
(define/public (make-kern-table-key left right)
(cons left right))
(define/public (encode-text str)
(for/list ([c (in-string str)])
(define cint (char->integer c))
(number->string (hash-ref win-ansi-table cint cint) 16)))
(define/public (glyphs-for-string str)
(for/list ([c (in-string str)])
(character-to-glyph (char->integer c))))
(define/public (character-to-glyph cint)
(define idx (hash-ref win-ansi-table cint cint))
(vector-ref characters (if (< idx (vector-length characters)) idx 0)))
(define/public (glyph-width glyph)
(hash-ref @glyph-widths glyph 0))
(define/public (get-kern-pair left right)
(hash-ref @kern-pairs (make-kern-table-key left right) 0))
(define/public (advances-for-glyphs glyphs)
(for/list ([left (in-list glyphs)]
[right (in-list (append (cdr glyphs) (list #\nul)))])
(+ (glyph-width left) (get-kern-pair left right))))))
(define win-ansi-table
(hasheqv 402 131
@ -113,117 +117,80 @@
381 142
382 158))
(define/contract (encodeText this str)
(string? . ->m . (listof string?))
(for/list ([c (in-string str)])
(define cint (char->integer c))
(number->string (hash-ref win-ansi-table cint cint) 16)))
(define/contract (glyphsForString this str)
(string? . ->m . (listof any/c))
(for/list ([c (in-string str)])
(send this characterToGlyph (char->integer c))))
(define/contract (characterToGlyph this cint)
(integer? . ->m . any)
(define idx (hash-ref win-ansi-table cint cint))
(vector-ref characters (if (< idx (vector-length characters)) idx 0)))
(define/contract (widthOfGlyph this glyph)
(string? . ->m . number?)
(hash-ref (· this glyphWidths) glyph 0))
(define/contract (getKernPair this left right)
((or/c char? string?) (or/c char? string?) . ->m . number?)
(hash-ref (· this kernPairs) (make-kern-table-key left right) 0))
(define/contract (advancesForGlyphs this glyphs)
((listof any/c) . ->m . (listof number?))
(for/list ([left (in-list glyphs)]
[right (in-list (append (cdr glyphs) (list #\nul)))])
(+ (send this widthOfGlyph left) (send this getKernPair left right))))
(define characters
(list->vector
(string-split
@string-append{ .notdef .notdef .notdef .notdef
.notdef .notdef .notdef .notdef
.notdef .notdef .notdef .notdef
.notdef .notdef .notdef .notdef
.notdef .notdef .notdef .notdef
.notdef .notdef .notdef .notdef
.notdef .notdef .notdef .notdef
.notdef .notdef .notdef .notdef
space exclam quotedbl numbersign
dollar percent ampersand quotesingle
parenleft parenright asterisk plus
comma hyphen period slash
zero one two three
four five six seven
eight nine colon semicolon
less equal greater question
at A B C
D E F G
H I J K
L M N O
P Q R S
T U V W
X Y Z bracketleft
backslash bracketright asciicircum underscore
grave a b c
d e f g
h i j k
l m n o
p q r s
t u v w
x y z braceleft
bar braceright asciitilde .notdef
Euro .notdef quotesinglbase florin
quotedblbase ellipsis dagger daggerdbl
circumflex perthousand Scaron guilsinglleft
OE .notdef Zcaron .notdef
.notdef quoteleft quoteright quotedblleft
quotedblright bullet endash emdash
tilde trademark scaron guilsinglright
oe .notdef zcaron ydieresis
space exclamdown cent sterling
currency yen brokenbar section
dieresis copyright ordfeminine guillemotleft
logicalnot hyphen registered macron
degree plusminus twosuperior threesuperior
acute mu paragraph periodcentered
cedilla onesuperior ordmasculine guillemotright
onequarter onehalf threequarters questiondown
Agrave Aacute Acircumflex Atilde
Adieresis Aring AE Ccedilla
Egrave Eacute Ecircumflex Edieresis
Igrave Iacute Icircumflex Idieresis
Eth Ntilde Ograve Oacute
Ocircumflex Otilde Odieresis multiply
Oslash Ugrave Uacute Ucircumflex
Udieresis Yacute Thorn germandbls
agrave aacute acircumflex atilde
adieresis aring ae ccedilla
egrave eacute ecircumflex edieresis
igrave iacute icircumflex idieresis
eth ntilde ograve oacute
ocircumflex otilde odieresis divide
oslash ugrave uacute ucircumflex
udieresis yacute thorn ydieresis})))
(map symbol->string
'(.notdef .notdef .notdef .notdef
.notdef .notdef .notdef .notdef
.notdef .notdef .notdef .notdef
.notdef .notdef .notdef .notdef
.notdef .notdef .notdef .notdef
.notdef .notdef .notdef .notdef
.notdef .notdef .notdef .notdef
.notdef .notdef .notdef .notdef
space exclam quotedbl numbersign
dollar percent ampersand quotesingle
parenleft parenright asterisk plus
comma hyphen period slash
zero one two three
four five six seven
eight nine colon semicolon
less equal greater question
at A B C
D E F G
H I J K
L M N O
P Q R S
T U V W
X Y Z bracketleft
backslash bracketright asciicircum underscore
grave a b c
d e f g
h i j k
l m n o
p q r s
t u v w
x y z braceleft
bar braceright asciitilde .notdef
Euro .notdef quotesinglbase florin
quotedblbase ellipsis dagger daggerdbl
circumflex perthousand Scaron guilsinglleft
OE .notdef Zcaron .notdef
.notdef quoteleft quoteright quotedblleft
quotedblright bullet endash emdash
tilde trademark scaron guilsinglright
oe .notdef zcaron ydieresis
space exclamdown cent sterling
currency yen brokenbar section
dieresis copyright ordfeminine guillemotleft
logicalnot hyphen registered macron
degree plusminus twosuperior threesuperior
acute mu paragraph periodcentered
cedilla onesuperior ordmasculine guillemotright
onequarter onehalf threequarters questiondown
Agrave Aacute Acircumflex Atilde
Adieresis Aring AE Ccedilla
Egrave Eacute Ecircumflex Edieresis
Igrave Iacute Icircumflex Idieresis
Eth Ntilde Ograve Oacute
Ocircumflex Otilde Odieresis multiply
Oslash Ugrave Uacute Ucircumflex
Udieresis Yacute Thorn germandbls
agrave aacute acircumflex atilde
adieresis aring ae ccedilla
egrave eacute ecircumflex edieresis
igrave iacute icircumflex idieresis
eth ntilde ograve oacute
ocircumflex otilde odieresis divide
oslash ugrave uacute ucircumflex
udieresis yacute thorn ydieresis))))
(module+ test
(define afmfont (AFMFont-open "data/helvetica.afm"))

@ -36,18 +36,18 @@
(send @dictionary end))
(define/override (encode text [options #f])
(define encoded (send font encodeText text))
(define glyphs (send font glyphsForString text))
(define advances (send font advancesForGlyphs glyphs))
(define encoded (send font encode-text text))
(define glyphs (send font glyphs-for-string text))
(define advances (send font advances-for-glyphs glyphs))
(define positions
(for/list ([glyph (in-list glyphs)]
[advance (in-list advances)])
(+glyph-position advance 0 0 0 (send font widthOfGlyph glyph))))
(+glyph-position advance 0 0 0 (send font glyph-width glyph))))
(list encoded positions))
(define/override (string-width str size [options #f])
(define glyphs (send font glyphsForString str))
(define advances (send font advancesForGlyphs glyphs))
(define glyphs (send font glyphs-for-string str))
(define advances (send font advances-for-glyphs glyphs))
(define width (apply + advances))
(define scale (/ size 1000.0))
(* width scale))))
@ -62,7 +62,7 @@
[(_ HASH-ID FONT-ID ...)
(with-syntax ([(PATH-STR ...) (map (λ (stx) (format "data/~a.afm" (syntax->datum stx))) (syntax->list #'(FONT-ID ...)))])
#'(begin (define-runtime-path FONT-ID PATH-STR) ...
(define HASH-ID (make-hash (list (cons (symbol->string 'FONT-ID) (procedure-rename (λ () (file->string FONT-ID)) 'FONT-ID)) ...)))))]))
(define HASH-ID (make-hash (list (cons (symbol->string 'FONT-ID) (procedure-rename (λ () (open-input-file FONT-ID)) 'FONT-ID)) ...)))))]))
(define-afm-table standard-fonts
Courier-Bold

Loading…
Cancel
Save