PGPLOT metafile driver

Author

T. J. Pearson, 1997.

Supported device

This PGPLOT driver creates a disk file in the private PGPLOT metafile format. [Do not confuse this format with other formats, such as the Windows Metafile format.]Files in this format can be read into a PGPLOT program with subroutine pgrdmf and displayed on another PGPLOT device.

The device driver is written in standard Fortran-77 and can be used with all operating systems for which PGPLOT is available.

The PGPLOT metafile is a plain ASCII text file; it can be transferred from one machine to another using standard channels (e.g., ftp, e-mail). The first five characters in the file must be %PGMF to identify the file type. PGPLOT metafiles can contain more than one picture (``page''). PGPLOT metafiles may be concatenated: the resulting file is also a valid PGPLOT metafile. Files can be substantially compressed by using standard utilities such as gzip.

It should be fairly easy to write translation programs to convert files from this format to another graphics format.

Device specification

filename/PGMF
-/PGMF

Supply any file name suitable for use on the host operating system. The default file name is pgplot.pgmf. If the file already exists, it will be overwritten (unless the operating system can create multiple versions of the file).

If the filename is ``-'', the file will be sent to the standard output and can be piped into another program (on operating systems that support this).

Default view surface dimensions

The default view surface is 6400×4800 units, with a nominal scale and resolution of 1000 units per inch (about 40 units per mm). The actual scale can be changed when the metafile is displayed. The default can be overridden by calling pgpap in the PGPLOT program, or, if pgpap is not used, by setting environment variables (logical names in VMS):

• PGPLOT_PGMF_WIDTH (default 6400)
• PGPLOT_PGMF_HEIGHT (default 4800)

These variables specify width and height in metafile units.

Color capability

Color indices 0-255 are available; color indices 0-15 have the standard PGPLOT default color representations, with white background (color index 0) and black foreground (color index 1). The RGB representation of any color index can be changed by calling pgscr. The default representations of color indices 0 and 1 can be changed with PGPLOT environment variables, e.g.

• PGPLOT_BACKGROUND (default white)
• PGPLOT_FOREGROUND (default black)

Input capability

None (non-interactive device).

Limitations

1. Only one PGPLOT device of this type may be opened at once.
2. The driver does not yet support the image functions (routines pgimag, pggray, etc.).