Xwin32

X-Win32 is the name of an X-server product for Windows that lets you display back from remote machines over X11 to your local Windows computer. With its default settings, X-Win32 tends to have some difficulties with OpenGL applications such as VisIt. This is one reason we discourage its use.

We instead hope you consider installing the native Windows version of VisIt on your local Windows computer and run client/server if you need to access data on a remote computer. This offers the following benefits:

  • Your gui button clicks won't have to go over the network so interaction will be faster
  • You are not relying on any potentially buggy X-server for your windowing and OpenGL support
  • VisIt 2.4.1 and later can tunnel SSH connections through a gateway computer, enabling client server access to network's such as LLNL's RZ.

In the event that you need to run an X-server on Windows, we'd instead recommend the X-server bundled with Cygwin since it seems to have better OpenGL support.

Configuring X-Win32

If you must use X-Win32, first try running VisIt from the remote computer, displaying back through X-Win32. If you are able to create plots using the X-Win32's default settings, then you might be in business without having to make any configuration changes. X-Win32 9.3 on Windows 7/64-bit offers decent rendering performance for VisIt's basic plots, at least, and does not require the X-Server to render OpenGL using a slower software renderer.

If performance is too slow then you can try:

  • Using VisIt 2.4.2 or later (there are rendering performance improvements)
  • Turn off Axes in the Annotation window. The Axes are updated often and require new geometry to be sent to the X-server, which reduces the frame rate that can be achieved. If you turn off the Axes then you will get better performance.

Using software rendering

If X-Win32 is not properly drawing VisIt's plots or if there are issues updating the windows then you might try forcing X-Win32 to use software rendering. This situation is more common with older versions of X-Win32 or running on older hardware. Software rendering should only be used as a last resort but sometimes it helps X-Win32 work better with OpenGL applications such as VisIt.

  1. Open the XWin32 X-Config
  2. Go to tab Window
  3. Check OpenGL software rendering checkbox
  4. Uncheck any checkbox related to direct2d
  5. Click Apply button

After following these steps, VisIt may work but it will not be using hardware-accelerated graphics. If you notice sluggishness due to poor rendering performance or delays introduced by a slow network when interacting with plots then you should install the native Windows version of VisIt and run client/server. As of VisIt 2.4.1, running client/server is enabled for computer systems that require access through a gateway computer.