Reference TCustomGraph

  TCustomGraph = class(TCustomWidget)
  protected
    function DefaultColor: TColorF; virtual;
    function DefaultMax: Double; virtual;
    function DataPoint: Double; virtual;
    function InfoText: string; virtual;
    procedure Paint(Stage: TPaintStage); override;
    property Max: Double read FMax;
  public
    constructor Create(Parent: TWidget; const Name: string = ''); override;
    { Update takes the next data points. It is called each time the graph is
      painted, so it does not need to be called by a scene. }
    procedure Update; virtual;
    { The time in seconds between data points }
    property FrameMeasure: Double read FFrameMeasure write FFrameMeasure;
    { The distance in pixels between data points }
    property Step: Float read FStep write FStep;
    { The room kept at the left of the graph for its label }
    property LabelMargin: Float read FLabelMargin write FLabelMargin;
  end;