render() {

		let progress = this.playing ? this.progress : 0,
			radius = ( this.diameter2 ) - this.thickness,
			x = this.diameter2,
			y = this.diameter2,
			iconSize = 28;

		// Ease towards 1
		this.progressOffset += ( 1 - this.progressOffset ) * 0.1;

		const endAngle = ( - Math.PI / 2 ) + ( progress * ( Math.PI * 2 ) );
		const startAngle = ( - Math.PI / 2 ) + ( this.progressOffset * ( Math.PI * 2 ) );

		this.context.save();
		this.context.clearRect( 0, 0, this.diameter, this.diameter );

		// Solid background color
		this.context.beginPath();
		this.context.arc( x, y, radius + 4, 0, Math.PI * 2, false );
		this.context.fillStyle = 'rgba( 0, 0, 0, 0.4 )';
		this.context.fill();

		// Draw progress track
		this.context.beginPath();
		this.context.arc( x, y, radius, 0, Math.PI * 2, false );
		this.context.lineWidth = this.thickness;
		this.context.strokeStyle = 'rgba( 255, 255, 255, 0.2 )';
		this.context.stroke();

		if( this.playing ) {
			// Draw progress on top of track
			this.context.beginPath();
			this.context.arc( x, y, radius, startAngle, endAngle, false );
			this.context.lineWidth = this.thickness;
			this.context.strokeStyle = '#fff';
			this.context.stroke();
		}

		this.context.translate( x - ( iconSize / 2 ), y - ( iconSize / 2 ) );

		// Draw play/pause icons
		if( this.playing ) {
			this.context.fillStyle = '#fff';
			this.context.fillRect( 0, 0, iconSize / 2 - 4, iconSize );
			this.context.fillRect( iconSize / 2 + 4, 0, iconSize / 2 - 4, iconSize );
		}
		else {
			this.context.beginPath();
			this.context.translate( 4, 0 );
			this.context.moveTo( 0, 0 );
			this.context.lineTo( iconSize - 4, iconSize / 2 );
			this.context.lineTo( 0, iconSize );
			this.context.fillStyle = '#fff';
			this.context.fill();
		}

		this.context.restore();

	}
Renders the current progress and playback state.