Category : Dbase (Clipper, FoxBase, etc) Languages Source Code
Archive   : DB3TOOLS.ZIP
Filename : CPAINTIT.DOC

PAINTIT dBASE III(1) Screen Paint/Load Call Routine
© 1986, Kenneth E. Wilson, Digital Equipment Corporation

This program is provided to the DECdomain with the condition that it
not be sold or included in any application which is sold. This program
is not warranted or guarranteed nor is it supported by its author. Any
problems found in this application should be logged in the dBASE notesfile.

This routine when loaded will print the Rainbow video screen from a specified
disk file. If the file cannot be read an error message will appear on the
screen and the routine will exit normally. Nothing will be written to the
screen unless the above error occurs. This routine is intended ONLY for
the following system configuration: RAINBOW 100A/B, dBASE III V1.1 on
MS-DOS(3) V2.11 or later.

To enable use of PAINTIT issue the following dBASE III command:
.LOAD PAINTIT

The call is structured as follows:

CALL PAINTIT WITH 'filename'
^ ^
|- Function |- Standard valid MS-DOS filespec
name

The file used in this call MUST have been saved by the call SAVEIT from this
author or by the program DO-IT and SWITCH-IT/DESK(2). PAINTIT remembers the
width of the screen on its last call and expects the screen width to remain
constant, i.e. if your first call is with a screen image file for a 132
column screen and you change the screen width after the call to 80 column,
and the next image file you call PAINTIT with is also for a 132 column
screen then the video ram will be corrupted. To prevent this from happening
simply change the screen back to 132 before calling PAINTIT with the second
file. Note: the reason for processing the screen width in this way is the
extremely slow Rainbow screen width change function. With PAINTIT
remembering the last screen width subsiquent paints are MUCH faster.

One other note on PAINTIT is that the name of the last file painted is
remembered for 'redisplaying'. If the entire filespec on the second call is
exactly the same as the prior call then no disk access will take place. The
copy of the file that is already in memory will be reused.

See the SAVEIT and PRINTIT routines also available from this author.

This routine may work on dBASE III V1.0, but specific loading and calling
syntax is different and as I understand V1.0 only one routine can be loaded
at any one time.

(1) dBASE III is a trademark of Ashton-Tate
(2) SWITCH-IT/DESK is a trademark of VuSoft
(3) MS is a trademark of MicroSoft