Transparency in fonts?

I just replied in http://forum.espruino.com/conversations/371038/#comment16334287 but just a note that if you don't need it to be fast, you can use a s normal font and then render it 'jittered' either side of where you want:

var txt = "Hello";
var x=10, y=10;
g.setFontVector(60).setColor("#fff");
g.drawString(txt,x-4,y).drawString(txt,x+4,y);
g.drawString(txt,x,y-4).drawString(txt,x,y+4);
g.drawString(txt,x-3,y-3).drawString(txt,x-3,y+3);
g.drawString(txt,x+3,y-3).drawString(txt,x+3,y+3);
g.setColor("#000");
g.drawString(txt,x,y);

I seem to remember we do this for one or two clock faces. If it's once a minute it's no big deal but you wouldn't want to be drawing like that every second.