ctx.lineTo(startPos * colWidth, pad);
// This next lineTo helps ensure that the shape of the line looks
// congruous to any specials on the same line
ctx.lineTo(Math.min(startPos, endPos) * colWidth, height / 2.0);
ctx.lineTo(endPos * colWidth, height - pad);
ctx.lineTo(endPos * colWidth, height);
ctx.stroke();
}
else
{
// something special