README.DVX file for DESQview/X port of xearth, version 1.1
Gary Welles
March 16, 2004

Kirk Lauritz Johnson's XEarth 1.1 is a significant improvement over
the bogus and unauthorized "version 0.6" shipped with DESQview/X.

Notable changes with this DV/X port are the wait timer which now
allows for nearly pixel perfect, just in time update timing.

-wait secs
     This uses DESQview API Timer Management Functions and differs
from the distribution in that the timer runs concurrently so that
XEarth updates _every_ wait secs instead of waiting wait secs
_between_ updates.  With XEarth updating every wait secs, DESQview
suspends it only for any remaining time between updates.  The accurate
update timing allows calculating an optimum time to wait between
position changes.  See -neat parameter.

-neat
     Neat (experimental in the DV/X port) "on" will cause XEarth to
calculate wait secs between changes in XEarth's position and use that
time in lieu of the wait secs parameter.  This should be equivalent to
wait 0, except for waiting instead of processing redundant updates.
While not perfect for all views, it should work best with the default
orthographic projection postioned above the tropics.  The default is
"off".

-fork|-nofork and -nice are not available.

Note: XEarth does not accept command line options for XWindow display,
only options in the resource file (xearth.res) will be processed.

My earlier port of XEarth 1.0 mistakenly added an unnecessary
"-timeoffset secs" resource to correct for local time.  Use instead a
time zone environment in AUTOEXEC.BAT like this for US Eastern Time:

              set TZ=EST+5EDT,M4.1.0/2,M10.5.0/2

:: TZ - Time zone environment variable
:: TZ=zone[-]offset[dst[offset][,start[/time],end[/time]]]
:: <http://www.cs.vu.nl/pub/minix/2.0.2/wwwman/man5/TZ.5.html>
::
:: Examples:
::   tz=UTC0
::   tz=CET-1CEST,M3.5.0/2,M10.5.0/3
::   tz=GMT0BST,M3.5.0/1,M10.5.0/2
::   tz=PST8PDT,M4.1.0/2,M10.5.0/2
::   tz=NZST-12NZDT,M10.1.0/2,M3.3.0/3

This port of Xearth to DESQview/X requires GO32.exe and a minimum
1024x768 - 256 color display mode.  The binary (xearth.exe) was
compiled for i486 (see makefile.dvx) and has been tested on both a
Pentium I and an i386 with math coprocessor.

The modifications to the source code (xearth.h, xearth.c and x11.c)
make use of the DESQview API, and all are #ifdef-ed MSDOS.
