home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
OK PC 9: IX-95
/
OKPC #9 IX-95.iso
/
dos
/
arcade
/
drobos
/
readme.not
< prev
next >
Wrap
Text File
|
1995-06-04
|
5KB
|
118 lines
This file has some notes from me to other programmers interested in the
dirty details of drobos ie. nothing interesting, so please go away..
When I ordered the book, all I knew about it was the name and a tiny 1
inch high picture in an ad. If I had known it was a graphics library, I
hadn't ordered it, but now.. Well, I don't like wasting money, so I
desided to give it a try. After having done drobos, I'm content with it.
GRAPHICS LIBRARY
================
I've used "the graphics Programming PowerPack", which is "a special
version of Genus Microprogramming's GX Development Series - a graphics
library that supports all graphics primitives" library that I got with
the "Graphics Programming PowerPack" (GPPP) book by Michael Jones (ISBN
0-672-30120-2 24.95 USD, floppy included with libs + one sample game).
The sample game is "Apples & Oranges" (reversi), which is available in
some ftp-places, too. IMHO not very encouraging sample, but at least it
was a fully functional game to study.
mode dh EGA 320x200x16
mode eh EGA 640x200x16
mode fh EGA 640x350x2
mode 10h EGA 640x350x16
mode 11h VGA 640x480x2
mode 12h VGA 640x480x16
There's total 104 functions selected from all the Genus GX libraries.
There's pc speaker music, including background playing.
There's 3 ROM fonts.
There's 6 PCX functions.
There's mouse routines, virtual screen support, 10 graphic effects.
Hongkong Mahjong was written with Genus GX according to its manual.
WEIRD BUGS
==========
- it looks like background music disturbs writing on-screen, at least in
Large model. When updating "points" numbers quite often got scrambled
and the only reason for this that I can think of is background music. I
recompiled drobos in Small model and haven't noticed it anymore. I must
have misused something and then fixed it without knowing it. Now I'm
back in Large model, keeping my fingers crossed and all is well..
- using pcx-routines messed up the palette, but that was really caused
by the pcx-file that was created with a Windows 3.1 application. I
loaded the pic into DOS program and saved as another file. All fixed.
- cursor flickered very badly, it looked like it was being drawn by the
GPPP as a normal colored picture. Now I use my own mouse routines, so
all troubles with mouse are caused by me.
- doesn't restore the used mode *exactly* as it was (hi Ronny :), but
neither do any other similar routine. This is really not a bug.. mode
is just restored in a way, where I have no control over it whatsoever.
- in one (network) machine the music was totally unrecognizable, like
the timer INT rate was set way too slow. Could network activity have
messed the background music playing.. it got better after a few tries.
- gxSetPaletteColor works in EGA only, so I rewrote all the palette
routines. If there are any trouble related to colors, that's because of
me, not GPPP.
- GPPP manual says: grOutText.. the CP does _not_ advance unless the
horizontal justification setting is grTLEFT. Well, the following..
grSetTextJustify(grTCENTER,grTCENTER);
grMoveTo(100,100); grOutText("test line 1");
grMoveRel(0,15); grOutText("test line 2");
grMoveRel(0,15); grOutText("test line 3");
..proves that this is not true. The Current Position (CP) does advance.
Summary: please don't get me wrong, I do like this library. There's no
perfect bug-free and fully documented library. If you think you have
one, just send it to and I'll find you a couple "undocumented features".
BGI vs. GPPP
============
IMHO GPPP could be faster than BGI and since the virtual screen routines
offer over 64k get/putimage possibilities there's something extra, too.
The graphics effects and music are quite cute..
Still BGI has stroked fonts, 256 color palette routines and some useful
functions such as draw/fillpoly, vertical text, arc etc.
Most professional game writers want to use only their own routines or at
least have the source available, but for amateurs like me GPPP isn't too
bad, provided that you have some means to fill the holes/nags in GPPP.
The full Genus GX libraries seem quite attractive, but as a poor student
I don't even dare to think about the price..
CD ROM SUPPORT
==============
If CDTMP is set and current disk is write-protected, then use the cdtmp
path, else use current directory. If you have a better idea about CD
support, please tell me, too..
char str[128], *cdtmp;
cdtmp = getenv("CDTMP");
if (*cdtmp && testdisk()) { strcpy(str,cdtmp); strcat(str,"\\"SCOREFILE); }
else strcpy(str,SCOREFILE);
if ((fp = fopen(str,"rb")) == NULL) bogus_score();
else { ... }
--jouni jon@stekt.oulu.fi
You have been reading my own personal opinions and nobody has paid me
anything to write good nor bad things about BGI or GPPP. Just IMHO..