If I have the following basic drawing of a triangle in JavaScript canvas, how would I rotate it, say 30 degrees, along the center? This is a bit different then the possible duplicate because it isn't a `rect`, it is a bunch of lines along an origin.

```
// Rotate 30 degrees when origin is (5,5)
ctx.beginPath();
ctx.moveTo(5,0);
ctx.lineTo(10,10);
ctx.lineTo(0,10);
ctx.lineTo(5,0);
ctx.stroke();

```

So, instead of seeing a normal triangle, you would see a triangle a bit tilted.

Thanks in advance!