ParaView looks for a few environment variables that can be used to modify its behavior. Environment variables are only accessed from the first process which contains the user interface. ParaView is responsible for broadcasting the effects of the modifications to all processes.
PV_OFFSCREEN
This environment variable is important only when running with multiple processes. It determines whether off screen rendering will be used for the satellite processes. The default behavior is for each node to map a window and use hardware rendering. When the assigned processors do not have access to a display, this environment variable should be set to "True" (any value will do). When this variable is set, ParaView only maps the render window of the first process. Software render will be used for the other processes. Of course, using software rendering will affect ParaView's rendering performance.
It is important to note that currently, you must link against Mesa's OpenGL libraries to get off-screen rendering on Unix systems. See ParaView FAQ on the web page for more up-to-date information.
PV_SEPARATE_RENDER_WINDOW
Setting this environment variable to "True" (or any value) will cause ParaView to create a render window separate from its main interface window.