api.cs

// create a drawing control that contains the shape(s)
TXTextControl.Drawing.TXDrawingControl drawingGroup =
    new TXTextControl.Drawing.TXDrawingControl(3000, 3000);

// create a new donut shape
TXTextControl.Drawing.Shape donut =
    new TXTextControl.Drawing.Shape(TXTextControl.Drawing.ShapeType.Donut) {
        Location = new Point(100, 100),
        Size = new Size(500,500)
    };

TXTextControl.Drawing.Shape diamond =
    new TXTextControl.Drawing.Shape(TXTextControl.Drawing.ShapeType.Diamond);

// add the shape to the drawing control
drawingGroup.Shapes.Add(donut);
drawingGroup.Shapes.Add(diamond);

// create a new drawing frame object from the created drawing control
TXTextControl.DataVisualization.DrawingFrame frame = 
    new TXTextControl.DataVisualization.DrawingFrame(drawingGroup);

// add the frame to the document
textControl1.Drawings.Add(
    frame, 
    textControl1.InputPosition.Location, 
    TXTextControl.FrameInsertionMode.DisplaceText);