On the Tools menu, click Import Drawing. The option to import a drawing is also available on the Drawings sidebar, or using the keyboard shortcut Ctrl+I.
Use this option to add a new DWG, DXF, or image file to a T3D file. On the Microsoft Open dialog select the drawing, and then click Open. The drawing will be displayed in a new window. The Drawing Settings dialog will also appear. The two main areas on the dialog are "Set Drawing Scale" and "Set Mapping to Model".
Input two points
Click this button after entering a measurement in the "Distance between points" box. Select two points on the drawing a known distance apart using the left mouse button. The scale of the drawing will be determined by these points.
Distance between points
Enter a known distance between two distinct points on the drawing. The distance apart will be used to set the drawing scale. This will be achieved by clicking on "Input two points" and then selecting two points on the drawing a known distance apart.
Snap distance
Enter a snap distance which is used whenever "Snap to Drawing" is activated.
Input drawing and model points
Click this button and then select a point on the drawing and a coincident point on the existing geometry to align the drawing with the existing model.