public override void Paint(float cx, float cy, ICanvas canvas)
{
var blockWidth = 4 * Scale;
var top = cy + Y + Renderer.TopPadding;
var bottom = cy + Y + Renderer.Height - Renderer.BottomPadding;
var left = cx + X + 0.5f;
// big bar
var h = bottom - top;
canvas.FillRect(left, top, blockWidth, h);
// line
left += (blockWidth * 2) - 0.5f;
canvas.BeginPath();
canvas.MoveTo(left, top);
canvas.LineTo(left, bottom);
canvas.Stroke();
//circles
left += 3 * Scale;
var circleSize = _circleSize * Scale;
var middle = (top + bottom) / 2;
canvas.FillCircle(left, middle - (circleSize * _dotOffset), circleSize);
canvas.FillCircle(left, middle + (circleSize * _dotOffset), circleSize);
}