By default, VisIt's Mesh plot draws in opaque mode so that hidden surface removal is performed when the plot is drawn and each face of the externally visible cells are outlined with lines. When the Mesh plot's opaque mode is set to automatic, the Mesh plot will be drawn in opaque mode unless it is forced to share the visualization window with other plots, at which point the Mesh plot is drawn in wireframe mode. When the Mesh plot is drawn in wireframe mode, only the edges of each externally visible cell face are drawn, which prevents the Mesh plot from interfering with the appearance of other plots. In addition to having an automatic opaque mode, the Mesh plot can be forced to be drawn in opaque mode or wireframe mode by clicking the On or Off Radio buttons to the right of the Opaque mode label in the Mesh plot attributes window.