Importing DXF Files

Model Size—Incoming geometry is evaluated to determine its bounding box size. This field displays the scene extents based on three factors:

Note: If the size cannot be determined, the field will show (Drawing Extents Not Known).

Rescale—Allows rescaling of the incoming geometry by a factor corresponding to the most common unit type used. The importer will try to detect the units of the DXF file being imported, compare those units with the 3ds Max system units, and provide the appropriate conversion factor.

For example: if a DXF file is saved using millimeter units and 3ds Max has its System Units set to 1.0 inches, the AutoCAD DWG/DXF Import Options dialog will automatically be set with Rescale turned on and the Incoming File Units set to millimeters.

Note: If the units are unspecified in the drawing, the list will appear blank. In this case, if the Import button is pressed and the Rescale toggle is turned on, you are prompted to select a value for Incoming File Units, and returned to the AutoCAD DWG/DXF Import Options dialog.

Incoming File Units—A drop down menu where you can set the scene units.

Combine Objects by Layer—Names each imported object based on the AutoCAD object's layer. The imported object name has a “Layer:” prefix and is followed by the layer name. For example, an AutoCAD object on the layer WALLS becomes Layer:Walls.

Create One Scene Object For Each ADT Object—Architectural Desktop (ADT) objects are imported as a single object instead of being separated into their constituent components. This means that if you import an ADT door object, the door is represented as one object instead of three. Turning on this switch make importing faster and the scene size is smaller.

Note: This switch presents several modeling concerns that you need to be aware of:

Weld—Sets whether coincident vertices of converted objects are welded according the to Weld Threshold setting. Welding smoothes across seams and unifies normals of objects with coincident vertices. To use the Weld option, first turn on Convert To Single Objects, because welding occurs only for vertices that are part of the same object.

Weld Threshold—Sets the distance that determines whether vertices are coincident. If the distance between two vertices is less than or equal to the Weld Threshold, the vertices are welded together.

Auto-smooth—Assigns smoothing groups according to the Smooth Angle value. Smoothing groups determine whether faces on an object render as a smooth surface or display a seam at their edges, creating a faceted appearance.

Smooth Angle—Controls whether smoothing occurs between two adjacent faces. If the angle between the two face normals is less than or equal to the smooth angle, the faces are smoothed.

Unify Normals—Analyzes the face normals of each object and flips normals where necessary, so they all point out from the center of an object. If the imported geometry is not properly welded, or if the software can’t determine the object's center, normals might be oriented in the wrong direction. Use the Edit Mesh or Normal modifiers to flip normals.

When Unify Normals is turned off, normals are calculated according to the face vertex order in the DXF file. For instance, face normals for AutoCAD ACIS solids are already unified. Turn off Unify Normals when importing ACIS solid models from AutoCAD.

Cap Closed Entities—Applies an extrude modifier to all closed entities, and turns on the Cap Start and Cap End options of the modifier. The Extrude modifier Amount value for a closed entity with no thickness is set to 0. Capping makes closed entities with thickness appear solid and closed entities without thickness appear flat. When Cap Closed Entities is turned off, the Extrude modifier Cap Start and Cap End options for closed entities with thickness are turned off. No modifiers are applied to closed entities without thickness, except for Circle, Trace, and Solid.

Texture Mapping—The texture mapping settings affect the loading time of models that have many objects with stored UVW Coordinates for texture mapped materials.

Note: This setting only applies to geometry that is stored as a mesh in the scene. Spline shapes marked as renderable have separate controls for UVW coordinate generation on the Spline Rendering panel.

Curve Steps—Adjusts how smoothly an arc or curve appears when the drawing is imported. Larger numbers result in smoother curves. Default=10.

Surface Deviation For 3D Solids—Specifies the maximum allowable distance from the 3ds Max surface mesh to the parametric ACIS surface. Small numbers produce more accurate surfaces with a greater number of faces. Large numbers produce less accurate surfaces with fewer faces.

This group allows you to toggle the inclusion of specific parts of a DWG file during the file link process.

External references—Imports xrefs attached to the DWG file.

Hatches—Imports hatches from the DWG file.

Warning: This stores each line or dot in the hatch pattern as a separate component of the VIZBlock that defines the hatch; this can create a very large number of objects in your scene.

Points—Imports points from the DWG file.

Lights—Imports lights from the DWG file.

Views (cameras)—Imports cameras from the DWG file, and converts them to 3ds Max cameras.

UCSs (grids)—Imports user coordinate systems (UCS) from the DWG file and converts them to 3ds Max grid objects.

This interface is very similar to the Layer Manager. Layer names remain the same as specified in the DXF file.

Skip all Frozen Layers—Excludes the import of AutoCAD objects on layers that are Off or Frozen.

Select from List—Allows you to choose specific layer that get imported.

All—The All button is only active when Select from List is turned on. It quickly lets you select all the layer in the list.

None—The None button is only active when Select from List is turned on. It deselects any layers you've selected.

Invert—The Invert button is only active when Select from List is turned on. Clicking this button reverses the selection set. Currently selected layers are unselected and unselected layers are selected.

Layer List—This field displays all the layers that make up the drawing and shows their status such as on/off, frozen/unfrozen or locked/unlocked.

The controls on this panel are identical in name and operation to those found on the Rendering rollout of an Editable Spline. The values of these settings are ‘set’ for all imported shapes. Once the import is complete, you can change the settings as necessary for each object.

Enable In Renderer—When on, the shape is rendered as a 3D mesh using the Radial or Rectangular parameters set for Renderer. In previous versions of the program, the Renderable switch performed the same operation.

Enable In Viewport—When on, the shape is displayed in the viewport as a 3D mesh using the Radial or Rectangular parameters set for Renderer. In previous versions of the program, the Display Render Mesh performed the same operation.

Use Viewport settings—Lets you set different rendering parameters, and displays the mesh generated by the Viewport settings. Available only when Enable in Viewport is turned on.

Generate Mapping Coords—Turn this on to apply mapping coordinates. Default=off.

3ds Max generates the mapping coordinates in the U and V dimensions. The U coordinate wraps once around the spline; the V coordinate is mapped once along its length. Tiling is achieved using the Tiling parameters in the applied material. For more information, see Mapping Coordinates.

Real-World Map Size—Controls the scaling method used for texture mapped materials that are applied to the object. The scaling values are controlled by the Use Real-World Scale settings found in the applied material's Coordinates rollout. Default=on.

Auto Smooth—If Auto Smooth is turned on, the spline is auto-smoothed using the threshold specified by the Threshold setting below it. Auto Smooth sets the smoothing based on the angle between spline segments. Any two adjacent segments are put in the same smoothing group if the angle between them is less than the threshold angle.

Threshold—Specifies the threshold angle in degrees. Any two adjacent spline segments are put in the same smoothing group if the angle between them is less than the threshold angle.

Viewport—Turn this on to specify Radial or Rectangular parameters for the shape as it will display in the viewport when Enable in Viewport is turned on.

Renderer—Turn this on to specify Radial or Rectangular parameters for the shape as it will display when rendered or viewed in the viewport when Enable in Viewport is turned on.

Radial—Displays the 3D mesh as a cylindrical object.

Thickness—Specifies the diameter of the viewport or rendered spline mesh. Default=1.0. Range=0.0 to 100,000,000.0.

Sides—Sets the number of sides (or facets) for the spline mesh n the viewport or renderer. For example, a value of 4 results in a square cross section.

Angle—Adjusts the rotational position of the cross-section in the viewport or renderer. For example, if the spline mesh has a square cross section you can use Angle to position a "flat" side down.

Rectangular—Displays the spline's mesh shape as a rectangle.

Length—Specifies the size of the cross–section along the local Y axis.

Width—Specifies the size of the cross–section along the local X axis.

Angle—Adjusts the rotational position of the cross-section in the viewport or renderer. For example, if you have a square cross-section you can use Angle to position a "flat" side down.

Aspect—Sets the aspect ratio for rectangular cross-sections. The Lock check box lets you lock the aspect ratio. When Lock is turned on, Width is locked to Length that results in a constant ratio of Width to Length.