diff --git a/fontland/fontland/font.rkt b/fontland/fontland/font.rkt index 87a9fad2..c38a4363 100644 --- a/fontland/fontland/font.rkt +++ b/fontland/fontland/font.rkt @@ -78,27 +78,29 @@ https://github.com/mbutterick/fontkit/blob/master/src/TTFFont.js #:script [script #f] #:language [lang #f] #:direction [direction #f]) - (define buf (hb-buf font)) - (hb_buffer_reset buf) - (when script - (hb_buffer_set_script buf script)) - (when lang - (hb_buffer_set_language buf (hb_language_from_string lang))) - (when direction - (hb_buffer_set_direction buf direction)) - (define codepoints (for/list ([c (in-string str)]) (char->integer c))) - (hb_buffer_add_codepoints buf codepoints) - (hb_shape (hb-font font) buf (map (λ (fpr) (tag->hb-feature (car fpr) (cdr fpr))) features)) - (define gis (hb_buffer_get_glyph_infos buf)) - (define hb-gids (map hb_glyph_info_t-codepoint gis)) - (define hb-clusters (break-at codepoints (map hb_glyph_info_t-cluster gis))) - (define hb-positions (map hb_glyph_position_t->list (hb_buffer_get_glyph_positions buf))) - (define glyphs (for/vector ([gidx (in-list hb-gids)] - [cluster (in-list hb-clusters)]) - (get-glyph font gidx cluster))) - (define positions (for/vector ([posn (in-list hb-positions)]) - (apply +glyph-position posn))) - (glyphrun glyphs positions)) + (match (for/list ([c (in-string str)]) (char->integer c)) + [(? null?) (glyphrun (vector) (vector))] + [codepoints + (define buf (hb-buf font)) + (hb_buffer_reset buf) + (when script + (hb_buffer_set_script buf script)) + (when lang + (hb_buffer_set_language buf (hb_language_from_string lang))) + (when direction + (hb_buffer_set_direction buf direction)) + (hb_buffer_add_codepoints buf codepoints) + (hb_shape (hb-font font) buf (map (λ (fpr) (tag->hb-feature (car fpr) (cdr fpr))) features)) + (define gis (hb_buffer_get_glyph_infos buf)) + (define hb-gids (map hb_glyph_info_t-codepoint gis)) + (define hb-clusters (break-at codepoints (map hb_glyph_info_t-cluster gis))) + (define hb-positions (map hb_glyph_position_t->list (hb_buffer_get_glyph_positions buf))) + (define glyphs (for/vector ([gidx (in-list hb-gids)] + [cluster (in-list hb-clusters)]) + (get-glyph font gidx cluster))) + (define positions (for/vector ([posn (in-list hb-positions)]) + (apply +glyph-position posn))) + (glyphrun glyphs positions)])) #|