[Back] [Up] [Next]

## Depth testing for 3D Label plots

Figure 20

When VisIt draw plots in the visualization window, the plots' geometries often correspond to only the outer surfaces of the originating datasets when those datasets are 3D. This means that the majority of plots consist of convex geometry and the normal test for only drawing labels that face front is often adequate to remove any labels that appear on faces that point away from the current camera. Some plots have geometries that consist of many concave regions, which the afore-mentioned test does not handle well. Plots with concave geometries will often have various pieces be incorrectly visible because though the surfaces may face the camera, they may be obscured by other geometry. When VisIt's Label plot draws 3D geometry, it tries to enable additional depth testing to prevent front-facing labels in back of other surfaces from being drawn. Depth testing can degrade performance so, by default, it is allowed only when you are running VisIt on your local workstation. You can set the Label plot's depth test mode to tell VisIt when to enable depth testing. To change the values for the depth test mode, click on one of the Auto, Always, Never radio buttons to the right of the Depth test mode label. If VisIt wants to use depth testing but is not allowed to then a warning message will be issued and you can set the depth test mode to Always.