The Render window is used to export the currently displayed graphics scene to an image file or to a geometric scene description file suitable for use by one of several external renderers, which can produce a final image. The supported rendering packages are listed in table 8.1. See Chapter 8 for detailed information on how rendering is performed using external programs, as well as information on 3-D printing and other uses of the exported scene description files.
The rendering process works in two stages. The first stage exports the displayed VMD scene to a text or image file in the selected format. The second (optional) stage renders the exported file, potentially displaying the results when complete. The exported file is named in the Filename field; a default name is given when a new format is selected, so it is best to hold off entering the filename until after the file format is selected. Another way to select the filename is available by pressing the Browse button, which opens up a file browser. Pressing the Start Rendering button writes the data file. After that, the Render Command is executed. The default command should start the appropriate rendering program if it is available.
Some of the rendering commands have been set to call a display program on the rendered image when it is completed. VMD will wait for the display program to finish, which causes VMD to freeze until the display program closes, so you may want to run the job in the background. This can be done (on Unix) by enclosing the existing text with ()'s and putting an & at the end. For example, the way to make the Raster3D render command run in the background is:
(render < %s -sgi %s.rgb; ipaste %s.rgb)&