Get dimensions for PNG image

physikerwelt · physikerwelt · commit 56b8d9852428 · 2016-02-13T21:54:43.000+01:00
* Get the dimensions for the PNG image
diff --git a/lib/mj-single.js b/lib/mj-single.js
@@ -230,7 +230,7 @@ function ConfigureMathJax() {
         //
         //  Don't need the styles
         //
-        delete SVG.config.styles
+        delete SVG.config.styles;
 
         SVG.Augment({
           //
@@ -266,7 +266,7 @@ function ConfigureMathJax() {
               //  then set the role and mark it as being processed
               //
               jax = script.MathJax.elementJax; if (!jax) continue;
-              jax.SVG = {display: (jax.root.Get("display") === "block")}
+              jax.SVG = {display: (jax.root.Get("display") === "block")};
               span = div = HTML.Element("span",{
                 style: {"font-size": this.config.scale+"%", display:"inline-block"},
                 className:"MathJax_SVG", id:jax.inputID+"-Frame", isMathJax:true, jaxID:this.id
@@ -487,7 +487,11 @@ function GetSVG(result) {
   //  Add the requested data to the results
   //
   if (data.svg) result.svg = svgdata;
-  if (data.png) result.svgfile = svgfile;
+  if (data.png) {
+      result.svgfile = svgfile;
+      result.width = svg.getAttribute("width").replace("ex","")*jax.SVG.ex;
+      result.height = svg.getAttribute("height").replace("ex","")*jax.SVG.ex;
+  }
   if (data.mathoidStyle) {
     if (data.svg) result.svg = svgfile;
     result.mathoidStyle = [
@@ -504,6 +508,8 @@ function GetPNG(result) {
     var Readable = require('stream').Readable;
     var s = new Readable();
     var svgfile = result.svgfile; delete result.svgfile;
+    var width = result.width; delete result.width;
+    var height = result.height; delete result.height;
     if (data.png) {
         try {
             var svgRenderer = new rsvg();
@@ -514,8 +520,9 @@ function GetPNG(result) {
             var synch = MathJax.Callback(function () {
             }); // for synchronization with MathJax
             svgRenderer.on('finish', function () {
-                var buffer = svgRenderer.render({format: 'png', width:600, height:600}).data;
-                result.png = "data:image/png;base64,"+(buffer||"").toString('base64');
+                console.log(JSON.stringify(result));
+                var buffer = svgRenderer.render({format: 'png', width: width, height: height}).data;
+                result.png = "data:image/png;base64," + (buffer || "").toString('base64');
                 synch();
             });
             s.pipe(svgRenderer);
diff --git a/test/png.js b/test/png.js
@@ -9,7 +9,8 @@ tape('basic test: check MathJax core', function(t) {
     mjAPI.typeset({
         math: tex,
         format: "inline-TeX",
-        png: true
+        png: true,
+        mathoidStyle: true,
     }, function (data) {
         t.equal(data.png.indexOf("data:image/png;base64"), 0, 'PNG has header.');
         t.ok(data.png.length > 100, 'PNG has a certain length');
