GETTING INTO PC CODING? (Hork)

                         by Chris Evans


It's  hard to ignore that huge PC market waiting for your games and
apps, even though AMOS and the Amiga are a sweet combination.

The  serious  PC  coding  is  done  in  C++  using add-on libraries
(extensions).  There are shareware C++ compilers like GNU C/C++ but
the  big  3  commercial  ones  are  Borland  4.5,  Watcom 10.6, and
Microsoft Visual C++ 4.0.

These  all  have  educational pricing at about 50-60 UKP if you can
order  on educational letterhead, with a full retail price of about
200-300  UKP.   There  are  other  brands  but  they don't get much
attention on the Net conferences.

Watcom  is  the  leader  in  game development, making such games as
Doom,  Indy Car Racer, XCom, Wacky Wheels, because it's regarded as
the best code optimizer.

By the way, ID Software has released the code for Wolfenstein 3D on
the  Internet.   Their  readme  file says they've done this because
they no longer use that engine, and have improved it alot, but they
thought  coders  would be interested.  Well, it caused quite a stir
on  the  Net, lots of discussion, and I've finally sucked under and
gone  and  downloaded  it,  but haven't dug through it yet.  If you
want it, it's a 570K zipped file called:

WOLFSRC.zip

and  it's  location has been moved around but if you do a Lyco file
search  it  will  pop  up somewhere.  Get ahold of me if you strike
out.

One big tip is to do 32-bit coding rather than 16-bit, which avoids
all  sorts  of  memory  hassles,  the  main  one being the 640K DOS
barrier,  and  provides a protected mode "flat" memory model, which
allows   your  program  to  access  extended  RAM  as  if  it  were
conventional memory.

32-bit's  flat  memory  also  eliminates  the  64K segment limit in
normal  memory,  so  you can have arrays of almost any size without
having  huge  pointers.  Bitmaps, image buffers and other arrays no
longer have the 64K restraint.

And  32-bit  provides better program performance, really noticeable
in 256 color graphics modes.  Don't pick a compiler that doesn't do
32-bit.

How  do they do this?  They have what are called DOS Extenders that
allow  for  protected mode programs to run under DOS.  They do this
by  executing  a real mode stub program that switches the processor
to  protected  mode and passes control to your program.  When a DOS
service  such  as  disk access is required it switches back to real
mode  to  satisfy  the  request, and after completion it reverts to
protected mode again until your program terminates.

Another   big   step   is   to   choose   a  good  add-on  assembly
graphics/animation  library  to handle your killer sprites, sort of
like  getting  a super AMAL.  There are lots of these, but not many
good ones.

A  fairly  good  one  is  Fastgraph  4.0 at about 150 UKP, and this
company  is  always  at  the  computer  graphics  shows  and  has a
hospitality  suite  and the works (see what your 150UKP buys).  But
smarter  dudes  than me say it is restrictive, even though the free
demo disk does some cool anims.  You can request their demo package
at this e-address:

72000.1642@compuserve.com

But  another  top  library,  and  much cheaper, is Word-Up Graphics
(WGT)  4.0  and  5.0  by  the  Egerter  brothers.  Version 4 is for
Borland Turbo C++ 3.0 and version 5 is for Watcom.  Version 4 works
in  lo-res  (320x200x256)  which  is  no good for CAD, but fine for
arcade  games.  It's $40 CAN.  Have a look at demo #20, a top- down
arcade  scroll with lots of space ships and missiles, like Galax on
the  AMOS  Pro  Compiler  extras disk.  If you want it download and
unzip this file off the Internet:

WGT40.zip

Version 5 is the head honcho, and does amazing stuff, and is priced
accordingly -- $300 CAN.

For  doing buttons and menus for apps, a neat one is SVGA-CC, which
has all kinds of gadgets.

Another anim lib that's interesting but not quite as cool is XSharp
version  2.2 by Mike Abrash, the graphics guru who has written lots
of  books.   It  has potential but the demos aren't as cool as WGT.
But  it's  offered  for  free,  and  it's on the Net, a file called
XSharp22.zip

Well  I  better  wrap up.  It's strange, but I have not seen 1 disk
mag or "club" for C++'ers.  Yea, I know, who'd want to be in a club
with PC losers, poor sots, ha ha.


Chris Evans
Internet:  Chris.Evans@onlinesys.com