Analog Clocks - programming hint

It's said that the essence of good Software Engineering is reuse (plagiarism?) so in developing my own analog clock faces, I have been looking through the code of many of the clocks in the BangleApps repository. In trying to get clock faces to render as quickly as possible, I found that the use of the Espruino graphics operation transformVertices from the builtin Graphics class helped enormously. Using the Github search facility, I found only two apps using the operation in BangleApps - neither are Analog Clocks - hence I hope the following example may be of interest. The example uses the the transformVertices operation in implementing the drawRotRect function used in the Beeb Clock (reuse in action).The function places a rectangle rotated around the centre of the clock dial at a parameterised distance from the centre of the clock. I have used it for the following Bold Clock influenced face:

The following are the functions to draw the dial and the hands of this clock.

    var cx = g.getWidth()/2;
    var cy = g.getHeight()/2

    Graphics.prototype.drawRotRect = function(w, r1, r2, angle) {
        var w2=w/2, h=r2-r1, theta=angle*Math.PI/180;
        return this.fillPoly(this.transformVertices([-w2,0,-w2,-h,w2,-h,w2,0], 
          {x:cx+r1*Math.sin(theta),y:cy-r1*Math.cos(theta),rotate:theta}));
    }
      
    function dial() {
        for (let a=0;a<360;a+=6)
        if (a % 90 == 0) 
            g.setColor(g.theme.fg).drawRotRect(8,105,120,a);
        else if (a % 30 == 0)
            g.setColor(g.theme.fg).drawRotRect(4,105,120,a);
        else 
            g.setColor(0.6,0.6,0.6).drawRotRect(2,110,120,a);
    }

let hourHand = g.drawRotRect.bind(g,6,6,66);
 let minuteHand = g.drawRotRect.bind(g,3,6,100);
 let secondhand = g.drawRotRect.bind(g,2,3,100);

This example uses a rectangle, however, the approach can just as easily be applied to polygons representing more complex hands.