Handle centerline for stretchy characters, and add centerline data to font files.

unpacked/jax/output/CommonHTML/fonts/TeX/AMS-Regular.js

@@ -24,6 +24,7 @@ var font = 'MathJax_AMS';
 
 CHTML.FONTDATA.FONTS[font] = {
   className: CHTML.FONTDATA.familyName(font),
+  centerline: 270, ascent: 1003, descent: 463,
   0x20: [0,0,250,0,0],               // SPACE
   0x41: [701,1,722,17,703],          // LATIN CAPITAL LETTER A
   0x42: [683,1,667,11,620],          // LATIN CAPITAL LETTER B

unpacked/jax/output/CommonHTML/fonts/TeX/Caligraphic-Bold.js

@@ -24,6 +24,7 @@ var font = 'MathJax_Caligraphic-Bold';
 
 CHTML.FONTDATA.FONTS[font] = {
   className: CHTML.FONTDATA.familyName(font),
+  centerline: 315, ascent: 840, descent: 211,
   weight: 'bold',
   skew: {
     0x41: 0.224,

unpacked/jax/output/CommonHTML/fonts/TeX/Fraktur-Bold.js

@@ -24,6 +24,7 @@ var font = 'MathJax_Fraktur-Bold';
 
 CHTML.FONTDATA.FONTS[font] = {
   className: CHTML.FONTDATA.familyName(font),
+  centerline: 259, ascent: 740, descent: 223,
   weight: 'bold',
   0x20: [0,0,250,0,0],               // SPACE
   0x21: [689,12,349,107,241],        // EXCLAMATION MARK

unpacked/jax/output/CommonHTML/fonts/TeX/Fraktur-Regular.js

@@ -24,6 +24,7 @@ var font = 'MathJax_Fraktur';
 
 CHTML.FONTDATA.FONTS[font] = {
   className: CHTML.FONTDATA.familyName(font),
+  centerline: 258, ascent: 740, descent: 224,
   0x20: [0,0,250,0,0],               // SPACE
   0x21: [689,12,296,91,204],         // EXCLAMATION MARK
   0x22: [695,-432,215,8,196],        // QUOTATION MARK

unpacked/jax/output/CommonHTML/fonts/TeX/Math-BoldItalic.js

@@ -24,6 +24,7 @@ var font = 'MathJax_Math-BoldItalic';
 
 CHTML.FONTDATA.FONTS[font] = {
   className: CHTML.FONTDATA.familyName(font),
+  centerline: 255, ascent: 725, descent: 216,
   weight: 'bold',
   style: 'italic',
   skew: {

unpacked/jax/output/CommonHTML/fonts/TeX/SansSerif-Bold.js

@@ -24,6 +24,7 @@ var font = 'MathJax_SansSerif-Bold';
 
 CHTML.FONTDATA.FONTS[font] = {
   className: CHTML.FONTDATA.familyName(font),
+  centerline: 250, ascent: 750, descent: 250,
   weight: 'bold',
   0x20: [0,0,250,0,0],               // SPACE
   0x21: [694,0,367,110,256],         // EXCLAMATION MARK

unpacked/jax/output/CommonHTML/fonts/TeX/SansSerif-Italic.js

@@ -24,6 +24,7 @@ var font = 'MathJax_SansSerif-Italic';
 
 CHTML.FONTDATA.FONTS[font] = {
   className: CHTML.FONTDATA.familyName(font),
+  centerline: 250, ascent: 750, descent: 250,
   style: 'italic',
     0x20: [0,0,250,0,0],               // SPACE
     0x21: [694,0,319,110,355],         // EXCLAMATION MARK

unpacked/jax/output/CommonHTML/fonts/TeX/SansSerif-Regular.js

@@ -24,6 +24,8 @@ var font = 'MathJax_SansSerif';
 
 CHTML.FONTDATA.FONTS[font] = {
   className: CHTML.FONTDATA.familyName(font),
+  centerline: 250, ascent: 750, descent: 250,
+  
   0x20: [0,0,250,0,0],               // SPACE
   0x21: [694,0,319,110,208],         // EXCLAMATION MARK
   0x22: [694,-471,500,32,325],       // QUOTATION MARK

unpacked/jax/output/CommonHTML/fonts/TeX/Script-Regular.js

@@ -24,6 +24,7 @@ var font = 'MathJax_Script';
 
 CHTML.FONTDATA.FONTS[font] = {
   className: CHTML.FONTDATA.familyName(font),
+  centerline: 211, ascent: 735, descent: 314,
   skew: {
     0x41: 0.389,
     0x42: 0.194,

unpacked/jax/output/CommonHTML/fonts/TeX/Typewriter-Regular.js

@@ -24,6 +24,8 @@ var font = 'MathJax_Typewriter';
 
 CHTML.FONTDATA.FONTS[font] = {
   className: CHTML.FONTDATA.familyName(font),
+  centerline: 233, ascent: 694, descent: 229,
+  
   0x20: [0,0,250,0,0],               // SPACE
   0x21: [622,0,525,206,320],         // EXCLAMATION MARK
   0x22: [623,-333,525,122,402],      // QUOTATION MARK

unpacked/jax/output/CommonHTML/fonts/TeX/fontdata.js

@@ -607,6 +607,7 @@
   CHTML.FONTDATA = CHTML.FONTDEF["TeX"];
 
   CHTML.FONTDATA.FONTS['MathJax_Caligraphic'] = {
+    centerline: 287, ascent: 789, descent: 216,
     skew: {
       0x41: 0.194,
       0x42: 0.139,
@@ -676,6 +677,7 @@
   };
 
   CHTML.FONTDATA.FONTS['MathJax_Main-Bold'] = {
+    centerline: 342, ascent: 951, descent: 267,
     weight: 'bold',
     file: "TeX/Main-Bold.js",
     Extra: [
@@ -817,6 +819,7 @@
   };
 
   CHTML.FONTDATA.FONTS['MathJax_Main-Italic'] = {
+    centerline: 250, ascent: 750, descent: 250,
     style: 'italic',
     0x20: [0,0,250,0,0],               // SPACE
     0x21: [716,0,307,107,380],         // EXCLAMATION MARK
@@ -941,6 +944,7 @@
   };
 
   CHTML.FONTDATA.FONTS['MathJax_Main'] = {
+    centerline: 314, ascent: 900, descent: 272,
     skew: {
       0x131: 0.0278,
       0x237: 0.0833,
@@ -1238,6 +1242,7 @@
   };
 
   CHTML.FONTDATA.FONTS['MathJax_Math-Italic'] = {
+    centerline: 250, ascent: 717, descent: 218,
     style: 'italic',
     skew: {
       0x41: 0.139,
@@ -1416,6 +1421,7 @@
   };
 
   CHTML.FONTDATA.FONTS['MathJax_Size1'] = {
+    centerline: 250, ascent: 850, descent: 350,
     0x20: [0,0,250,0,0],               // SPACE
     0x28: [850,349,458,152,422],       // LEFT PARENTHESIS
     0x29: [850,349,458,35,305],        // RIGHT PARENTHESIS
@@ -1464,6 +1470,7 @@
   };
 
   CHTML.FONTDATA.FONTS['MathJax_Size2'] = {
+    centerline: 249, ascent: 1360, descent: 862,
     0x20: [0,0,250,0,0],               // SPACE
     0x28: [1150,649,597,180,561],      // LEFT PARENTHESIS
     0x29: [1150,649,597,35,416],       // RIGHT PARENTHESIS
@@ -1504,6 +1511,7 @@
   };
 
   CHTML.FONTDATA.FONTS['MathJax_Size3'] = {
+    centerline: 250, ascent: 1450, descent: 950,
     0x20: [0,0,250,0,0],               // SPACE
     0x28: [1450,949,736,209,701],      // LEFT PARENTHESIS
     0x29: [1450,949,736,34,526],       // RIGHT PARENTHESIS
@@ -1528,6 +1536,7 @@
   };
 
   CHTML.FONTDATA.FONTS['MathJax_Size4'] = {
+    centerline: 250, ascent: 1750, descent: 1250,
     0x20: [0,0,250,0,0],               // SPACE
     0x28: [1750,1249,792,237,758],     // LEFT PARENTHESIS
     0x29: [1750,1249,792,33,554],      // RIGHT PARENTHESIS

unpacked/jax/output/CommonHTML/jax.js

@@ -33,8 +33,7 @@
 
   var EVENT, TOUCH, HOVER; // filled in later
 
-  var CENTERLINE = .25,
+  var STRUTHEIGHT = 1,
-      STRUTHEIGHT = 1,
       HFUZZ = .025, DFUZZ = .025;  // adjustments to bounding box of character boxes
 
   var STYLES = {
@@ -871,7 +870,7 @@
       char: function (item,node,bbox,state,m) {
         var font = item.font;
         if (state.className && font.className !== state.className) this.flushText(node,state);
-        if (!state.a) state.a = (font.centerline || CENTERLINE);
+        if (!state.a) state.a = font.centerline/1000;
         if (state.a > (bbox.a||0)) bbox.a = state.a;
         var C = font[item.n];
         state.text += C.c; state.className = font.className;
@@ -996,7 +995,7 @@
         var s = 1.1*(H - h)/k + .3;  // space to cover by extender
         s /= (ebox.h+ebox.d);        // scale factor;
         this.Transform(ext,
-          "translateY("+CHTML.Em(-ebox.d+.25-s*CENTERLINE)+") scaleY("+s.toFixed(3).replace(/0+$/,"")+")",
+          "translateY("+CHTML.Em(-ebox.d+.25-s*ebox.a)+") scaleY("+s.toFixed(3).replace(/0+$/,"")+")",
           "left "+CHTML.Em(ebox.d)
         );
         ext.style.paddingTop=ext.style.paddingBottom = 0;
@@ -1073,7 +1072,7 @@
       this.adjustHeights([left,ext,mid,ext2,right],hbox);
       if (ebox.D) ebox.d = ebox.D;
       hbox.t = hbox.h; hbox.b = hbox.d;
-      var mt = ebox.h - hbox.h - CENTERLINE, mb = ebox.d - hbox.d + CENTERLINE;
+      var mt = ebox.h - hbox.h - ebox.a, mb = ebox.d - hbox.d + ebox.a;
       if (mt) node.style.marginTop = CHTML.Em(mt);
       if (mb) node.style.marginBottom = CHTML.Em(mb);
       hbox.h = ebox.h; hbox.d = ebox.d;