public void RegisterBarRenderer(string key, BarRendererBase renderer)
{
if (!_barRendererLookup.ContainsKey(key))
{
_barRendererLookup[key] = new FastDictionary<string, BarRendererBase>();
}
_barRendererLookup[key][GetBarRendererId(renderer.Bar.Staff.Track.Index, renderer.Bar.Index)] = renderer;
}