Importing Wavefront Object (OBJ) Files
 
 
 
Command entry: Application menu Import Files of type gw::OBJ-Importer (*.OBJ)

Geometry imported from OBJ files appears in 3ds Max as editable mesh or editable poly objects. Import of associated materials and maps is supported.

NoteWhen you import an OBJ file by dragging and dropping, by default the importer does not display the OBJ Import Options dialog. To see the dialog, hold down the Ctrl key while you drag and drop.

Procedure

To import an OBJ file:

  1. From the Application menu, choose Import.

    The Select File To Import dialog opens.

  2. Choose an OBJ file to open and click Open.

    The importer dialog opens.

  3. Choose the objects to import and set the import parameters. For details, see the Interface section, following.
  4. Click Import.

    During import, a dialog showing progress and the names of imported objects opens. If a name conflict occurs, a dialog opens giving you the opportunity to skip or rename the object.

Interface

“LED” Icons for Options

The dialog indicates which features are in the OBJ file by means of red and green icons that look like LEDs.

This feature is present in the OBJ file.

This feature is not present in the OBJ file.

Objects group

Reset scene

Deletes the current scene from memory before importing the OBJ file.

Prefix

The importer prepends any text entered here to the name of each imported object.

Import as single mesh

When on, the importer combines the contents of the OBJ file into a single editable mesh object, and gives the object the same name as the file (without the file name extension).

For example, if you import as a single mesh a file named window_parts.obj, all separate objects in the OBJ file are combined into a single editable mesh object named “window_parts”.

Import as Editable Poly

When on, imports the Wavefront geometry as Editable Poly objects rather than Editable Mesh objects. Default=off.

Retriangulate Polygons

When on, ensures that imported polygons are triangular, as in Editable Poly surfaces. This can be useful when you import meshes from a modeling program that doesn’t ensure triangular polygons. Default=on.

WarningRetriangulate Polygons can alter the vertex order, so when this option is on, exporting a mesh back to the OBJ format won’t match the original mesh exactly. Some applications, such as Mudbox and ZBrush ® , depend on vertex order: if you are working with one of these, be sure to turn off Retriangulate Polygons.
TipWhen you import and export OBJ files used with a particular application, use presets to ensure consistency.
[file info]

Just above the list of objects in the file, appearing as read-only fields, are the name of the OBJ file and the total number of faces in the file.

[object list]

The objects in the imported OBJ file appear in this scrolling list. Each entry consists of an object name and the number of faces in the object, plus a check box to the left of the object name for enabling and disabling import per object.

By default, import is enabled for all objects in the file. To toggle import for an individual object, click its check box in the list. You can also use the controls at the bottom of the list to enable and disable import (see following).

All/None/Invert

Use these buttons to modify the state of the import enable/disable check boxes. All enables all objects in the list; None disables all objects; Invert reverses the state of each check box.

[text field]

Enter search phrases with wild cards into the editable text field to the right of the Invert button to enable only objects that satisfy the search criteria. For example, to enable all list items whose names start with “Sphere”, enter sph*.

You can also use the standard search character ? to represent a single character. For example, to enable all four-character names starting with “Box”, use the search string box?.

Geometry group

Flip ZY-axis

When on, transfers all Y-axis values to the Z axis and vice-versa. Use this when importing from Poser and other programs that use Y as the vertical axis and Z as the depth axis.

Center Pivots

Positions the pivot of each imported object at its center. When off, the pivots are positioned at the world center: (0,0,0).

Shapes/Lines

Enables import of splines.

Texture coordinates

When on, texture coordinates are loaded from the imported file, if present, and associated with the geometry.

Smoothing groups

When on, the information about color transitions between groups is loaded. See Viewing and Changing Smoothing.

Normals Group

These controls affect how normals are imported (or generated, if necessary).

  • Import from file (The default.) Imports the normals used in the OBJ file. If the OBJ file does not have normals, generates normals using the imported smoothing groups. If the OBJ file does not specify smoothing groups, generates normals by assigning all faces smoothing group 1.
  • From SM group Generates normals from imported smoothing groups. If the OBJ file does not specify smoothing groups, or you turn off Geometry Smoothing Groups, generates normals by assigning all faces smoothing group 1.
  • Auto Smooth Generates smoothing groups based on the angle between faces.

    [value] The threshold angle for generating smoothing groups: if the angle between two faces is less than this value, both are assigned to the same smoothing group. If the angle is greater than this value, the two faces are assigned to separate smoothing groups. Default=30.0.

  • Faceted All faces are assigned to smoothing group 0: that is, no smoothing is applied, and the imported mesh has a faceted appearance.
Flip Normals

Flips the normal of all imported faces. It doesn’t matter whether the normals are imported or generated.

This option is mainly for use when you are importing a model that appears “inside out” if you don’t flip the normals. Such models usually result when geometry is exported by an application other than Maya or 3ds Max.

Units/Scale group

convert

Turn on to enable unit conversion. Default=off.

  • Model Units Choose the unit to use when importing th e model. Most often, you will set this to the unit used in the original OBJ file.
Object Scale

When Convert is off, determines the scaling for the contents of the OBJ file on import. The default value of 1.0 means no scaling is performed.

Material group

Unique Wire Color

Determines the wireframe colors assigned when importing multiple objects without materials. When on, each object is assigned a different wireframe color. When off, each object is assigned the same wireframe color, picked at random.

Import Materials

When on, imports materials from the MTL file associated with the OBJ file. Default=on.

When off, the remaining controls in this group are disabled.

Prefix

Prepends the indicated text to the name of each imported material. Enter the prefix in the editable text field to the right of the Prefix check box.

Default bump

The default amount of bump maps if the value is not specified in the MTL file.

Force black ambient

Sets the Ambient component of imported materials to black.

Import into Mat-Editor

Brings imported materials into the Material Editor. If this is off at import time and you later want to edit a material, you need to use Get Material first.

Show maps in viewport

Turns on Show Map In Viewport for imported materials’ Diffuse maps.

Copy maps to project folder

When on, copies maps used by the OBJ file to the \scenassets\images subfolder of the current 3ds Max project folder. Default=off.

  • Overwrite Images When Copy Maps To Project Folder is on, turning on this option causes maps from the OBJ file to overwrite existing images that have duplicate names. Default=off.

    When Copy Maps is on but this option is turned off, 3ds Max displays the names of any maps it didn’t copy.

_____

Write log to Import-folder

Saves a log file to the same folder as the OBJ file when importing via script.

Preset Group

Preset

When importing from a specific application, choose that application from the list. Presets comprise all export settings, including geometry and materials.

[edit presets]

Click to open a dialog that lets you edit the presets. To change the map path for a preset, edit the map-path setting manually or click the folder button at the right end of the row and navigate to the new path.

While the Presets dialog is open, you can choose a preset by clicking its name (the row highlights) and then clicking OK.

_____

Import

Loads the designated files (OBJ + materials and maps) according to the current settings.

During the import, a dialog shows the progress. If a name conflict occurs, a dialog appears giving you the option to skip the duplicate object or rename it.

Cancel

Cancels the OBJ import.

Help

Opens the help file to this topic.

See Also