Update canvas2svg.js

Added textBaseline support.

canvas2svg.js

@@ -57,6 +57,27 @@
         lookup["\\xa0"] = ' ';
         return lookup;
     }
+
+    //helper function to shift y-coordinates by textBaseline 
+    function getTextBaselineOffset(textBaseline, fontSize) {        
+        var fontEmSize = parseFloat(fontSize); //support em ?
+        fontEmSize = fontEmSize / 1.25; //just a guess
+        var fontSize   = fontEmSize / 1.25; //just a guess
+        var offset;
+        if (textBaseline == "top") {
+            offset = fontEmSize;
+        } else if (textBaseline == "bottom") {
+            offset = fontSize - fontEmSize;
+        } else if (textBaseline == "middle") {
+            offset = fontSize/2;
+        } else if (textBaseline == "hanging") {
+            offset = fontSize;
+        } else {
+            //alphabetic normal:
+            offset = 0;
+        }
+        return offset;
+    }
 
     // Unpack entities lookup where the numbers are in radix 32 to reduce the size
     // entity mapping courtesy of tinymce
@@ -746,7 +767,7 @@
                 "font-weight" : font.weight,
                 "text-decoration" : font.decoration,
                 "x" : x,
-                "y" : y
+                "y" : y + getTextBaselineOffset(this.textBaseline, font.size)
             }, true);
 
         textElement.appendChild(document.createTextNode(text));