如何使用Raphael.js缩放文本

Question

I came to know about Raphael.js recently and I was trying to do some hands on. I would like to scale a text but it is not working. After searching a lot in Google I have not find any idea.

Code is:

var paper = Raphael("paper1", 1000,1000);

var txt = paper.text(20,50,"Hello World").attr({
"font-family":"Arial","font-size":"30px", "font-weight": "normal", 
fill: "#000000", stroke:"black", "stroke-width": "0px",
"text-anchor" : "start" , "font-style": "normal"});

flip is working by txt.scale(-1,1) but txt.scale(2,1) is not scaling the text.

Is there a way to scale a text?

Note: Font size of the text needs to remain same ie 30px in my case.

Answer 1

Is there a way to scale a text?

DEMO

I checked and it works like a charm

var r = Raphael('test');

var t = r.text(200, 100, "I am a text").attr({fill:'red', 'font-size':30});

$('#zoomin').click(function() {
    t.scale(2);
});

$('#zoomout').click(function() {
    t.scale(.5);
});

Answer 2

If we scale the text only then font size shall be changed. We need to convert the text into an image and the we need to scale it. To do that I have used a hidden canvas.

Following code works for me.

<canvas id='textCanvas' style="display:none"></canvas>

<script>
  var paper = Raphael("paper1", 1000,1000);
  var img =  paper.image(getTxtImg("Hello World","italic","bold","15px","arial",
                                       "#000000",130,35),20,28,300,80)

  img.scale(2,1)  //Double in width
  img.scale(.5,1)  //Half  in width

function getTxtImg(txt,style,weight,fontsize,fontfamily,color,w,h)
{
  var tCtx = document.getElementById('textCanvas').getContext('2d');
  tCtx.canvas.width = w;
  tCtx.canvas.height = h    ;
  var fontstr = "" + style + " " + weight + " " + fontsize + " " + fontfamily + " ";
  tCtx.font = fontstr
  tCtx.fillStyle  = color
  tCtx.fillText(txt, 0, h);
  return tCtx.canvas.toDataURL();
}
</script>