plane truth

pitfall/pitfall/core.rkt

@@ -40,7 +40,6 @@
                   id
                   ascender
                   descender
-                  upm
                   line-gap
                   bbox
                   ref

pitfall/pitfall/font-embedded.rkt

@@ -42,7 +42,6 @@ https://github.com/mbutterick/pdfkit/blob/master/lib/font/embedded.coffee
   (define unicode (mhasheq 0 '(0))) ; always include the missing glyph (gid = 0)
   (define widths (mhasheq 0 (glyph-advance-width (get-glyph font 0))))
   (define name (font-postscript-name font))
-  (define upm (font-units-per-em font))
   (define scale (/ 1000 (font-units-per-em font)))
   (define ascender (* (font-ascent font) scale))
   (define descender (* (font-descent font) scale))
@@ -50,20 +49,9 @@ https://github.com/mbutterick/pdfkit/blob/master/lib/font/embedded.coffee
   (define line-gap (* (font-linegap font) scale))
   (define encoding-cache (make-hash)) ; needs to be per font, not in top level of module
   (efont
-   name id ascender descender upm line-gap bbox #f #f efont-embedded efont-encode efont-measure-string
+   name id ascender descender line-gap bbox #f #f efont-embedded efont-encode efont-measure-string
    font subset unicode widths scale encoding-cache))
 
-(define (efont-measure-string ef str size [features null])
-  ; #f disables features ; null enables default features ; list adds features
-  (define scale (/ size (pdf-font-upm ef) 1.0))
-  ;; use `encode` because it's cached.
-  ;; we assume that the side effects of `encode`
-  ;; (e.g., appending to `widths` and `unicode`)
-  ;; are ok because every string that gets measured is going to be encoded eventually
-  (match-define (list _ posns) (efont-encode ef str features)) 
-  (define width (for/sum ([p (in-vector posns)]) (glyph-position-x-advance p)))
-  (* width scale))
-
 (define (efont-encode ef str [features-in null])
   (define features (sort (remove-duplicates features-in) bytes<? #:key car))
   (hash-ref! (efont-encoding-cache ef) (cons str features) 
@@ -89,6 +77,16 @@ https://github.com/mbutterick/pdfkit/blob/master/lib/font/embedded.coffee
                  (hash-ref! (efont-unicode ef) gid (λ () (glyph-codepoints glyph))))
                (list subset-idxs new-positions))))
 
+(define (efont-measure-string ef str size [features null])
+  ;; #f disables features ; null enables default features ; list adds features
+  ;; use `encode` because it's cached.
+  ;; we assume that the side effects of `encode`
+  ;; (e.g., appending to `widths` and `unicode`)
+  ;; are ok because every string that gets measured is going to be encoded eventually 
+  (define width (for/sum ([p (in-vector (glyphrun-positions (layout (efont-font ef) str #:features features)))]) (glyph-position-x-advance p)))
+  (define scale (/ size (+ (font-units-per-em (efont-font ef)) 0.0)))
+  (* width scale))
+
 (define (efont-embedded ef)
   (define isCFF (has-table? (efont-font ef) 'CFF_))
   (define font-file (make-ref))

pitfall/pitfall/font-standard.rkt

@@ -24,12 +24,11 @@
   (define kern-pairs (make-hash kps))
   (define ascender (string->number (hash-ref attributes 'Ascender "0")))
   (define descender (string->number (hash-ref attributes 'Descender "0")))
-  (define upm 1000)
   (define bbox (for/list ([attr (in-list (string-split (hash-ref attributes 'FontBBox)))])
                  (or (string->number attr) 0)))
   (define line-gap (- (third bbox) (first bbox) ascender descender))
   (sfont
-   name id ascender descender upm line-gap bbox #f #f sfont-embed sfont-encode sfont-measure-string
+   name id ascender descender line-gap bbox #f #f sfont-embed sfont-encode sfont-measure-string
    attributes glyph-widths kern-pairs))
 
 (define (sfont-embed sf)

pitfall/pitfall/text.rkt

@@ -48,7 +48,7 @@ https://github.com/mbutterick/pdfkit/blob/master/lib/mixins/text.coffee
 (define (add-text doc x y str features)
   (match-define (list encoded-char-strs positions) (encode (pdf-current-font doc) str features))
   
-  (define scale (/ (pdf-current-font-size doc) #;(pdf-font-upm (pdf-current-font doc)) 1000.0))
+  (define scale (/ (pdf-current-font-size doc) 1000.0))
   (define commands empty)
   
   ;; Adds a segment of text to the TJ command buffer