This creates a new window in the internal editor and opens the specified file in it. POV-Ray will attempt to set
the language type according to the extension. .POV and .INC files are assumed to be POV-Ray files and will have POV
syntax highlighting. If you use a different file extension for POV source code, you can set the language type manually
after you open it.
Note that POVWIN will not let you load more than one copy of the same file. If you attempt to load an
already-loaded file, that file will be selected as the current file in the editor, but nothing else will happen.