10.1.9 Displaying fitting online

While experimenting with the various fitting options listed in the preceding sections, you may find it useful to see the results of the fitting online. Limn can display the filtered (see section 10.1.4 Filtering curves) bitmap and the fitted outline online if it is run under the X window system and you specify `-do-display'.

Ordinarily, Limn stops at the end of fitting every character for you to hit return, so you have a chance to examine the result. If you just want to get a brief glimpse or something, you can specify `-display-continue'. Then Limn won't stop.

If you specify `-do-display', you must set the environment variable DISPLAY to the X server you want Limn to use. For example, in Bourne-compatible shells, you might do:

DISPLAY=:0 ; export DISPLAY

The output is shown on a grid, in which each square represents several pixels in the input. Corners are shown as filled squares; other pixels are shown as hollow squares.

Limn has several options that change the appearance of the online output:

• `-display-grid-size unsigned' The number of expanded pixels shown between the grid lines; default is 10.

• `-display-pixel-size unsigned' The expansion factor; i.e., each input pixel is expanded to a square this many pixels on a side; default is 9.

• `-display-rectangle-size unsigned' The pixel size; i.e., each pixel shown is a square this many pixels on a side; default is 6. This must be less than the `display-pixel-size', so that black pixels don't merge into each other.

You can change the size of the window Limn creates with the geometry resource in your `.Xdefaults' file (see the documentation in the file `mit/doc/tutorials/resources.txt' in the X distribution if you aren't familiar with X resources). The class name is Limn. For example:

Limn*geometry: 300x400-0-0

makes the window 300 pixels wide, 400 pixels high, and located in the lower right corner of the screen.