Page:NBS Technical Note 11176 (1983) (IAutilityprogramsf1176dick).djvu/25

 APPENDIX A

In order to illustrate the use of the character fonts created by use of the CANDY APPLE program, we have written a program named CANDY WRAPPER to place these characters anywhere on the hires screen. This program is given in Listing 4 and uses some of the routines developed for CANDY APPLE to decode end plot the characters. The program is menu driven with the following options available to the user:

1. Change the disk drives for inputting and outputting a hires picture.

2. Display the catalog of a selected disk drive.

3. Set the environment for drawing the hires characters. This option allows the user to select foreground and background colors from the hires color set.

4. Load a previously saved hires picture from disk.

5. Save a hires picture to disk.

6. Add text to a hires picture.

7. Change from one Hershey font to another.

8. Clear the hires screen.

9. Display the hires screen.

10. Exit the program.

In general, the program is self-explanatory and uses a non-destructive hires cursor to position the start of the Hershey character on the screen. The program does not clear the hires screen at initialization so that a previously generated picture may be left in page 1 for the addition of text. In addition, the program is relocated to protect the primary hires page. For convenience, the fonts are read in as 32 character increments called small, caps, numbers, and greek as stored by the program CANDY APPLE. Figure 9 illustrates a logo produced by CANDY WRAPPER as a frontispiece for a listing of CANDY APPLE. This figure end all others used in this report were produced by a screen dump of the hires graphic page produced by the programs to a dot-matrix printer. Utility Programs...