Merge pull request mozilla#2526 from yurydelendik/create-os2

brendandahl · brendandahl · commit 3aea29c7aa2a · 2013-01-08T12:11:42.000-08:00
Fixes creation of OS/2 table
diff --git a/src/fonts.js b/src/fonts.js
@@ -2646,25 +2646,25 @@ var Font = (function FontClosure() {
       lastCharIndex = 255;
     }
 
-    var unitsPerEm = override.unitsPerEm || PDF_GLYPH_SPACE_UNITS;
-    var typoAscent = override.ascent || properties.ascent;
-    var typoDescent = override.descent || properties.descent;
+    var bbox = properties.bbox || [0, 0, 0, 0];
+    var unitsPerEm = override.unitsPerEm ||
+      1 / (properties.fontMatrix || FONT_IDENTITY_MATRIX)[0];
+
+    // if the font units differ to the PDF glyph space units
+    // then scale up the values
+    var scale = properties.ascentScaled ? 1.0 :
+      unitsPerEm / PDF_GLYPH_SPACE_UNITS;
+
+    var typoAscent = override.ascent || Math.round(scale *
+      (properties.ascent || bbox[3]));
+    var typoDescent = override.descent || Math.round(scale *
+      (properties.descent || bbox[1]));
+    if (typoDescent > 0 && properties.descent > 0 && bbox[1] < 0) {
+      typoDescent = -typoDescent; // fixing incorrect descent
+    }
     var winAscent = override.yMax || typoAscent;
     var winDescent = -override.yMin || -typoDescent;
 
-    // if there is a units per em value but no other override
-    // then scale the calculated ascent
-    if (unitsPerEm != PDF_GLYPH_SPACE_UNITS &&
-        'undefined' == typeof(override.ascent)) {
-      // if the font units differ to the PDF glyph space units
-      // then scale up the values
-      typoAscent = Math.round(typoAscent * unitsPerEm / PDF_GLYPH_SPACE_UNITS);
-      typoDescent = Math.round(typoDescent * unitsPerEm /
-        PDF_GLYPH_SPACE_UNITS);
-      winAscent = typoAscent;
-      winDescent = -typoDescent;
-    }
-
     return '\x00\x03' + // version
            '\x02\x24' + // xAvgCharWidth
            '\x01\xF4' + // usWeightClass
@@ -5506,6 +5506,7 @@ var CFFParser = (function CFFParserClosure() {
         // adjusting ascent/descent
         properties.ascent = fontBBox[3];
         properties.descent = fontBBox[1];
+        properties.ascentScaled = true;
       }
 
       var charset, encoding;
