Improved font subsetting

Author: PhenX

classes/Font_Glyph_Outline.php

@@ -100,4 +100,8 @@ function encode(){
   function getSVGContours() {
     // Inherit
   }
+
+  function getGlyphIDs(){
+    // Inherit
+  }
 }

classes/Font_Glyph_Outline_Composite.php

@@ -126,7 +126,7 @@ function parseData(){
   function encode(){
     $font = $this->getFont();
 
-    $gids = array_values($font->getSubset());
+    $gids = $font->getSubset();
 
     $size  = $font->writeInt16(-1);
     $size += $font->writeFWord($this->xMin);

classes/Font_Table_cmap.php

@@ -115,26 +115,39 @@ protected function _parse(){
 
   function _encode(){
     $font = $this->getFont();
+
     $subset = $font->getSubset();
+    $glyphIndexArray = $font->getUnicodeCharMap();
+
+    $newGlyphIndexArray = array();
+    foreach ($glyphIndexArray as $code => $gid) {
+      $new_gid = array_search($gid, $subset);
+      if ($new_gid !== false) {
+        $newGlyphIndexArray[$code] = $new_gid;
+      }
+    }
+
+    ksort($newGlyphIndexArray); // Sort by char code
 
     $segments = array();
-    
-    $i = count($segments)-1;
-    $j = $i+1;
-    $prevCode = 0;
-    $glyphIndexArray = array();
 
-    foreach($subset as $code => $gid) {
-      if ($prevCode + 1 != $code) {
+    $i = -1;
+    $prevCode = 0xFFFF;
+    $prevGid = 0xFFFF;
+
+    foreach($newGlyphIndexArray as $code => $gid) {
+      if (
+        $prevCode + 1 != $code ||
+        $prevGid + 1 != $gid
+      ) {
         $i++;
         $segments[$i] = array();
       }
 
-      $segments[$i][] = array($code, $j);
+      $segments[$i][] = array($code, $gid);
 
-      $glyphIndexArray[] = $code;
-      $j++;
       $prevCode = $code;
+      $prevGid = $gid;
     }
 
     $segments[][] = array(0xFFFF, 0xFFFF);
@@ -184,7 +197,7 @@ function _encode(){
         "endCode"       => $endCode,
         "idDelta"       => $idDelta,
         "idRangeOffset" => $idRangeOffset, 
-        "glyphIndexArray" => $glyphIndexArray, 
+        "glyphIndexArray" => $newGlyphIndexArray,
       )
     );
 
@@ -217,7 +230,7 @@ function _encode(){
       $length += $font->w(array(self::uint16, $segCount), $subtable["startCode"]);
       $length += $font->w(array(self::int16, $segCount), $subtable["idDelta"]);
       $length += $font->w(array(self::uint16, $segCount), $subtable["idRangeOffset"]);
-      $length += $font->w(array(self::uint16, $segCount), $subtable["glyphIndexArray"]);
+      $length += $font->w(array(self::uint16, $segCount), array_values($subtable["glyphIndexArray"]));
 
       $after_subtable = $font->pos();
 

classes/Font_Table_glyf.php

@@ -42,7 +42,7 @@ public function getGlyphIDs($gids = array()){
       }
     }
 
-    return array_merge($gids, $glyphIDs);
+    return array_unique(array_merge($gids, $glyphIDs));
   }
 
   public function toHTML(){
@@ -108,12 +108,20 @@ public function toHTML(){
       $name = isset($names[$g]) ? $names[$g] : sprintf("uni%04x", $char);
       $char = $char ? "&#{$glyphIndexArray[$g]};" : "";
 
-      $s .= "<div"." class='glyph-view $type'>
+      $s .= "<div class='glyph-view $type' id='glyph-$g'>
               <span class='glyph-id'>$g</span> 
               <span class='char'>$char</span>
               <span class='char-name'>$name</span>
-              <br />
-              <canvas width='$width' height='$height' id='glyph-$g'></canvas>
+              ";
+
+      if ($type == "composite") {
+        foreach ($glyph->getGlyphIDs() as $_id) {
+          $s .= "<a href='#glyph-$_id' class='glyph-component-id'>$_id</a> ";
+        }
+      }
+
+      $s .= "<br />
+            <canvas width='$width' height='$height' id='glyph-canvas-$g'></canvas>
             </div>
             <script>Glyph.glyphs.push([$g,$shape_json]);</script>";
     }

classes/Font_Table_name.php

@@ -6,7 +6,7 @@
  * @license http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License
  */
 
-require_once dirname(__FILE__) . "/Font_Table_name_Tecord.php";
+require_once dirname(__FILE__) . "/Font_Table_name_Record.php";
 
 /**
  * `name` font table.

classes/Font_Table_name_Tecord.php renamed to classes/Font_Table_name_Record.php

@@ -169,45 +169,34 @@ function setSubset($subset) {
 
     $subset = array_unique($subset);
 
-    $subtable = null;
-    foreach($this->getData("cmap", "subtables") as $_subtable) {
-      if ($_subtable["platformID"] == 0 || $_subtable["platformID"] == 3 && $_subtable["platformSpecificID"] == 1) {
-        $subtable = $_subtable;
-        break;
-      }
-    }
+    $glyphIndexArray = $this->getUnicodeCharMap();
 
-    if (!$subtable) return;
+    if (!$glyphIndexArray) {
+      return;
+    }
 
     $gids = array(
-      0 => 0 // Required glyph
+      0, // .notdef
+      1, // .null
     );
+
     foreach($subset as $code) {
-      if (!isset($subtable["glyphIndexArray"][$code])) {
+      if (!isset($glyphIndexArray[$code])) {
         continue;
       }
-      
-      $gids[$code] = $subtable["glyphIndexArray"][$code];
+
+      $gid = $glyphIndexArray[$code];
+      $gids[$gid] = $gid;
     }
 
-    // add compound glyphs
     /** @var Font_Table_glyf $glyf */
     $glyf = $this->getTableObject("glyf");
     $gids = $glyf->getGlyphIDs($gids);
 
-    $gids_from_codes = array(
-      0 => 0 // Required glyph
-    );
-    foreach ($subtable["glyphIndexArray"] as $code => $gid) {
-      if (in_array($gid, $gids)) {
-        $gids_from_codes[$code] = $gid;
-      }
-    }
-
-    ksort($gids_from_codes);
+    sort($gids);
 
-    $this->glyph_subset = $gids_from_codes;
-    $this->glyph_all = $subtable["glyphIndexArray"];
+    $this->glyph_subset = $gids;
+    $this->glyph_all = array_values($glyphIndexArray); // FIXME
   }
 
   function getSubset() {
@@ -284,7 +273,7 @@ function parseTableEntries(){
       /** @var Font_Table_Directory_Entry $entry */
       $entry = new $class($this);
       $entry->parse();
-      
+
       $this->directory[$entry->tag] = $entry;
     }
   }

classes/Font_TrueType.php

@@ -108,3 +108,14 @@ hr {
 .glyph-view canvas {
   background: #fff;
 }
+
+.glyph-view:target {
+  outline: 2px dotted red;
+}
+.glyph-view:target canvas {
+  background: #ddffdd;
+}
+
+.glyph-view a.glyph-component-id {
+  font-size: 0.8em;
+}

www/css/style.css

@@ -12,7 +12,7 @@
   <link rel="stylesheet" href="css/blitzer/jquery-ui-1.8.14.custom.css" />
   <script type="text/javascript" src="js/jquery-1.5.1.min.js"></script>
   <script type="text/javascript" src="js/jquery-ui-1.8.14.custom.min.js"></script>
-  <script type="text/javascript" src="js/glyph.js?v=4"></script>
+  <script type="text/javascript" src="js/glyph.js?v=5"></script>
   <script type="text/javascript">
     $(function() {
       $("#tabs").tabs({

www/font_info.php

@@ -155,7 +155,7 @@ var Glyph = {
   },
   drawAll: function(){
     $.each(Glyph.glyphs, function(i, g){
-      Glyph.draw($('#glyph-'+g[0]), g[1], g[0]);
+      Glyph.draw($('#glyph-canvas-'+g[0]), g[1], g[0]);
     });
   },
   resize: function(value){