public ChordDiagramRenderer()
 {
     GuitarModel          = new GuitarModel();
     CurrentChordDiagrams = GuitarModel.GetPopularChordDiagrams();
 }
 public ChordDiagramRenderer(GuitarModel guitarModel)
 {
     GuitarModel          = guitarModel;
     CurrentChordDiagrams = GuitarModel.GetPopularChordDiagrams();
 }