Zortech problems

From: bright@sauk.Data-IO.COM Walter Bright bright at Data-IO.COM
Sat Feb 17 06:27:17 AEST 1990


In article <48a441bf.20b6d at apollo.HP.COM> nelson_p at apollo.HP.COM (Peter Nelson) writes:
<   What if I have a 1-hour program that I want to stop after 5 
<   minutes because I don't like the way it's turning out?   I could
<   type Break or ctrl-C except that once Zortech enters graphics
<   mode it disables this feature!

Not hardly. The graphics package does nothing with ^C. ^C is only checked
for by DOS when you call a DOS function. The graphics package does not
call DOS. If you want ^C checking, you'll need to sprinkle in a few
calls to DOS inbetween calls to the graphics routines.

<  And, as far as I can tell, none
<   of the "get" string or character functions (getc, getch, etc)
<   Zortech supplies will return without *waiting for a keystroke*,

Notice the standard function kbhit(), on pg. 245, which does exactly this.

<   An even more glaring problem is the apparent lack of any way
<   to output text in graphics mode!!!

I suppose it's glaring if you hadn't noticed the function fg_putc()
on pg. 182.

<   Finally, I tried running one of my programs, which ran just fine
<   on my own Hercules monochrome display, on a friend's 286 system
<   with a Paradise VGA card.  Zortech sez that at fg_init time they
<   check to see what kind of graphics card is present and set up
<   to output to that.  No such luck.  The software mangled the timing
<   of the VGA display and outputted ca-ca.

This'll happen if you do not have a multisync monitor and fg_init
switches it into a mode that your monitor does not support. Set
the environment variable FG_DISPLAY to a mode that both your graphics
board *and* your monitor support. See page 177-178 of your manual.

<   I've only used a tiny subset of Zortech's C and C++ and library
<   features and I'm dismayed at the number of problems I've already
<   found.

DOS programming, graphics programming, and C++ programming are all
complex subjects. All the 'problems' you're having appear to be caused
by lack of familiarity with these topics. I recommend that you read:

	1. Zortech C++ Function Reference
	2. MS-DOS Technical Reference
	3. Programmer's Guide to PC and PS/2 Video Systems



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