poor graphics performance in Navisworks

I found a great post the other day from Beyond Design that I thought I should share.  This is from 2011 but if you are experiencing a sluggish Navisworks some of this may be helpful.  Specifically the part I am interested in is below but the whole article is here.

The Model

Is it detailed? Is it large? How many triangles, you can find out under Project > Scene Statistics, compare this to what your card can handle? Models with lots of curves require more triangles, just get a piping model and switch to hidden line mode; you’ll see that this can build up quickly to create thousands and millions of triangles that need to be drawn. If you reduce the faceting factor (Options > File Readers), when bringing the native CAD file in, then this will reduce the number of triangles we use to draw the rounded item, lower it too much though and the item may look blocky, the default is set to 1.

Are there any parts of the model a long way away? Do a quick audit of the model by seeing if Zoom All zooms so far out you can’t see the model you expected. Use the Selection Box tool to work out what is distant from the model and see if you can change in the native application, if not then Hide it.

If you have set lots of the model to be required (i.e. prioritized when you are navigating) then you may experience lots of drop out of all the other items. Again, start from nothing (right click > Reset All > Unrequire All) and slowly build up adding those essential items.

Try running the model with ‘Scene Lights’ Lighting and ‘Shaded’ Mode on the Viewpoints tab, if this significantly improves performance then you might have over done it on the materials and lighting. Look at using the materials and lighting you need rather than going overboard and adding materials and lights to everything.

Improve the Showcase Performance

The Showcase Help is quite umm helpful…

Combine and separate objects to improve frame rate

Large production models, which typically have hundreds of parts that are comprised of thousands of surfaces and surface patches, can significantly slow Hardware rendering performance (the frame rate) while interactively authoring or presenting a scene.

You can improve the interaction performance (even with multiple production models loaded and displayed side by side) by combining objects in the Organizer. Combining objects essentially flattens the selected object hierarchy to speed the frame rate. However, to prevent data loss (for example, material assignments), you must follow the workflow guidelines and possibly modify your workflow.


Hierarchies or groups containing accent lights cannot be combined. The combine option will be grayed out and unavailable when these items are selected. Deselect or remove the accent lights from the group and then combine.

Follow these working guidelines to combine nodes successfully without losing important data:

  • Resist combining objects that go into different alternatives or behaviors. If you do combine the objects, the assignments may break, and you may need to redo the reassignments.
  • Precalculated ambient shadows may be adversely affected when you combine mixed geometry (for example, polys and NURBS). Before combining, occlusion is applied differently to different data types (for NURBS, through textures; for polys, through vertex colors); after combining, NURBS and polys textures are ignored, and all occlusion is vertex based.
  • Combining a shadow caster will result in the entire combined node being a shadow caster for that light.
  • Combining objects that may appear to have the same texture may cause the texture placement to shift or scale in unexpected ways. In this case, re-place the texture on the combined object.
  • You cannot combine a node that has already combined objects within it; the combine button and menu item is not available in this case. An alternative approach is to separate the combined node, then combine at a higher level of the hierarchy.
  • Combining should be done only if you are sure that nothing else is going to change in the geometry. If you combine and then decide to update or re-tessellate your model because of changes done in the originating application, you may encounter geometry issues.
  • When combining multiple objects with different materials, the first material found is applied to all. For example:
    • Object A is combined with Material A
    • Object B is combined with Material B

    If you combine those two objects, you get:

    • Object C With Material A
  • If you plan to animate objects, keep the objects separate.

To combine objects:

  1. In the Organizer, select the objects you want to combine, then group them. The objects are grouped into one folder.

  2. Right-click the folder with the grouped objects, and select Combine. The objects are combined and you can no longer expand the node to see its contents.


    Double-click the folder to folder to give it a more meaningful name.

You can separate combined objects to gain access to parts of the combined geometry to work with it (for example, to flip normals, to remove duplicate surface, or to split geometry to add different alternatives or behaviors).

Separating is not the same as undoing (Edit > Undo) the combination operation. Separating retains the object hierarchy but gives you access to combined objects; undoing reverts to the original object hierarchies within a scene session.

To separate objects:

  1. In the Organizer, select the combined objects you want to separate.
  2. Right-click the selected objects, and choose Separate. The objects are separated, and you can now expand the node to see its contents.