2010

Control Render Quality
Use Culling
Culling lets you navigate and manipulate large and complex scenes at interactive rates by intelligently hiding
less-important objects as you work.
In Autodesk Navisworks, you can use the following methods of culling objects:
■ Area - the objects’ size in pixels determines whether the objects are rendered or not. By default, any objects
smaller than 1x1 pixels in size are discarded.
■ Backface - by default, only the front face of every polygon is drawn in Autodesk Navisworks. Sometimes,
during the conversion process the front and back face of polygons get mixed, in which case, you need to
adjust the Backface option.
■ Near and Far Clipping Planes (frustum culling) - objects closer to the camera than the near clipping plane or
beyond the far clipping plane are not drawn. You can let Autodesk Navisworks automatically constrain the
location of the clipping planes, or you can constrain their location manually.
To set area culling
1 Click Tools ➤ File Options.
2 In the File Options dialog box, Culling tab, select the Enable check box in the Area section.
3 Enter a value for the screen area in pixels below which geometry objects are culled. For example, setting
this value to 100 pixels means that any object within the model that would be drawn less than 10x10 pixels
in size are discarded.
4 Click OK.
To turn on backface culling for all objects
1 Click Tools ➤ File Options.
2 In the File Options dialog box, Culling tab, select On in the Backface area.
3 Click OK.
To turn off backface culling for all objects
1 Click Tools ➤ File Options.
2 In the File Options dialog box, Culling tab, select Off in the Backface area.
3 Click OK.
To turn on backface culling only for solid objects
1 Click Tools ➤ File Options.
2 In the File Options dialog box, Culling tab, select Solid in the Backface area.
3 Click OK.
To constrain the position of the clipping planes automatically
1 Click Tools ➤ File Options.
2 In the File Options dialog box, click the Culling tab.
3 Select Automatic for the Near clipping plane.
4 Select Automatic for the Far clipping plane.
174 | Chapter 7 Control Model Appearance and Render Quality