Floppyshop 2/Floppyshop - 2.zip/Floppyshop - 2.iso/diskmags/5791-.end/dmg-6260/articles/link_rev.doc

Text File | 1993-08-20 | 14KB | 255 lines

               "THE MISSING LINK" EXTENSION REVIEW

Probably one of the most  exciting  things  that  can happen to an avid
STOS user is the release of a new extension, and the Missing Link is no
exception. I first heard about it from Goodman International P.D. and I
made an order straight away!

When booting up the  disk,  I  was  taken  to  the desktop with several
programs and five folders. I loaded  up the first program called BALLS.
I was then presented  with  a  rather  impressive 'asteroid' game, with
your spaceship flying around,  a  large  32x32  ball,  and a relatively
smooth  full-screen  multi-directional  scrolling  background!  Sampled
sound is included (not noticeably slowing  the  game down) and the ship
could fire up to about six bullets.

"OK...quite impressive" I thought to  myself  as  I completed the first
few levels. By the time I got to  a later level, there were five or six
32x32 balls flying  around,  a  full-screen multi-directional scrolling
background, your ship, up to 6  bullets  AND  sampled sound at the same
time, and running at the same speed as level 1 !!!

I quitted that program and loaded the next one up. This was an overhead
game where you control a  little  man  who  can  shoot bullets and some
attacking bees or something. Again, the  screen scrolls smoothly, and a
large amount of bees and bullets seemed  to  do little to slow down the
gameplay.

The next game was  a  side-on  vertically-scrolling  platform game. You
control a large car sprite in a  quest  to collect the coloured dots on
the level. Yet again, the scrolling  was  smooth and very fast (I think
either 1 or 2 VBL's to draw out the car and the tiled background!)

Then there was a typical shoot-'em-up,  with  you as a spaceship trying
to shoot down the flying  saucers  with  your rockets. This had sampled
sound, and yet again, about eight  32x16  aliens, the ship, and lots of
bullets were easily catered-for.

Next was a vertically-scrolling shoot-'em-up.  You start off very slow,
and you can  only  shoot  two  bullets  at  a  time.  Smooth scrolling.
Samples. Lots of aliens. Every  now  and  then, a destroyed alien would
release a power-up which either made  your ship go faster, or increased
your firepower.

The  penultimate  game  was  a  side-on  horizontally  and  vertically-
scrolling shoot-'em-up, with plenty of aliens and a large ship sprite.

Lastly, there was an overhead game,  with you controlling a ship flying
over a multidirectional background shooting the little metal spheres.

After playing these small demonstration  games,  I  had to admit, I was
very very impressed with what I had  seen. The games seemed to run many
times faster than what  I  had  thought  they  would  if someone was to
describe them to me. Little did I know...

I opened a folder and loaded  yet  another demonstration game. This was
called FRANK AND THE LOST AUBERGIENE. It was a side-on multidirectional
(again!) platform game with you as  a  little  man who must collect the
dots and the key to  the  exit  door.  The  sampled sound was good, the
graphics not-so-good...but the  graphics  aren't  on  review  here! You
could lay sticks of dynamite to destroy  the daleks and little men that
got in the way. This game  would  not have been recognisable as written
in STOS. But, there is still better to come...

The next game was called THE RACE  and  in my opinion was the best game
of the disk. The graphics, music, gameplay  were are of a very superior
quality. The game itself  was  just  like  something  out of SUPERCARS,
without the  violence.  The  screen  was  split  horizontally  down the
middle, and involved three cars  racing  around  a VERY smooth and fast
track in a race to  see  who  can  make  three  laps. One car is always
computer-controlled, but there is  a  two-player  option where a friend
can plug in another joystick and race as well! There are 20 tracks, and
you can get your  hands  on  the  track  construction  kit  for a small
registration fee.

The last game was called VIOLENT  DEATH.  This  is  a one or two player
horizontally-scrolling shoot-'em-up, where you  fly  through some caves
and generally blast everything you can see!

Once I has tried out all of  the  games,  I concluded that they all had
some things in common. They  were  all  VERY  fast,  they were all VERY
smooth, they all could handle tens of  sprites easily, most of them had
sampled sound or impressive 'decent' chip-music, and they all generally
were outside the limits  of  STOS.  The  reason?  Because they all used
commands from the new MISSING LINK extension!

One of the programs writes  the  documents,  example basic files, world
construction kit, and of course,  the  extensions themselves to a blank
disk. Rather excitedly, I read through the document...(which was rather
large!)

So...what new commands are  there,  then?  Well,  I  will  start off by
telling you that  there  are  59  of  them!  These  are  split into the
following categories: SPRITES, MAPS,  TEXT,  GRAPHICS, PALETTES, FILES,
SOUND, JOYSTICK, and MISCELLANEOUS.

There are two new and different  kinds of sprites, oddly-named BOBS and
JOEYS. According to the document, the  BOBS  command can handle over 25
16x16 sprites in 1 vbl! And, by  the  look of some of the example basic
files, I wouldn't doubt it! Things that are run directly from STOS look
as if they  have  been  compiled.  There  are  a  total  of  six sprite
commands.

The next section consists of  MAP  commands.  These are used to quickly
and simply draw up a map of  a  level at a certain position. The twelve
map commands allow for: setting window size, drawing maps regardless of
16-word  boundary,   drawing   maps   locked   onto   16-word  boundary
(landscapes), limit  testing,  toggling  between  maps  and landscapes,
placing, erasing and checking blocs.  There  are two different types of
map. WORLDS are  used  for  multidirectionally-scrolling games, because
you can draw from  ANY  point  on  the  screen  (-2,-3). LANDSCAPES are
identical to WORLDS except for they are locked onto the last 16th pixel
(as usual). This is marginally  faster  than  WORLDS,  and is ideal for
vertically-scrolling games, or to just draw out a section of a level.

There are two TEXT commands. One simply  places some text on the screen
at X,Y in a certain font. The other is a faster version of STR$.

The GRAPHICS  commands  are  the  most  powerful  of  the  Missing Link
commands. WIPE clears a whole screen (or  any 32K area of memory). TILE
fills the whole screen with a 16x16 graphic, at any X co-ord. MOZAIC is
the same as tile, but  within  a  predefined  window.  SPOT is a faster
version than PLOT. REFLECT produces an impressive 'river' effect at any
point on the screen -  reflecting  any  graphics  above it. WASH clears
part of a screen. BLIT is  a  faster  version  of SCREENCOPY. M BLIT is
identical to BLIT, but merges over graphics - like SCREEN$=SCREEN$. And
finally, DISPLAY PC1 unpacks a DEGAS .PC1 picture to any screen (within
half a second!)

The PALETTE commands are  also  impressive,  and  one  or  two are VERY
useful. The first is =PALT.  This  automatically grabs the palette from
ANY bob, joey, tile, world, landscape, or sprite bank. PALSPLIT sets up
a palette split down the  screen,  allowing  well  over 16 colours at a
time,  and,  used  in  conjunction  with  REFLECT,  can  give  a  great
impression of a river at the bottom  of  the screen. FLOODPAL is a very
handy command. It floods the  palette  with  a  colour stated after the
command, so, FLOODPAL 0 sets all  16  colours  to 0. Puts to rest those
PALETTE 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 nightmares!  =BRIGHTEST returns
the brightest colour at  a  certain  address.  This prevents any barely
visible displays during a game with colours constantly changing.

The next set of commands are  the  FILE commands. First, there is DLOAD
and DSAVE. These are like  binary  loading/saving,  except you can load
from or save to any part of a  file on the disk. Other commands include
the returning of  the  depacked  lengths  of  files,  and  bank copying
commands.

Next come the SOUND commands. DIGIPLAY  replays a sample of a specified
length, at  a  specified  frequency,  and  either  looped  or singular.
SAMSIGN is a handy command which  'inverses' a sample. For example, you
have to press CONTROL-S within some samplers  to convert it so STOS can
use them proporly. This simple command  does  it for you if you forget.
=MUSAUTO automatically plays some 'decent' music.  When I say decent, I
mean MAD MAX, COUNT ZERO, BIG ALEC  sort of music, not that crappy STOS
MUSIC ACCESSORY music.  It  understands  19  different formats. MUSPLAY
allows you to play music  manually,  and  can also handle special sound
effects.

The JOYSTICK commands allow you to read BOTH joystick ports!

Finally, there are six commands in the MISCELLANEOUS section. The first
one, which is rather impressive,  unpacks  files  that were packed with
ATOMIK 3.5 - ICE 2.4 - FIRE 2.2  -  AUTOMATION  5.1 - SPEED 2 - SPEED 3
packers. Just one command does  that!  One  command returns whether the
program is compiled or not. One relocates program files, so they can be
run from anywhere in memory. One  quickly  rounds  a number down to the
nearest 16. One detects  a  collision  between  two  defined boxes. And
finally, one forces a HARD RESET!

Whew! There we  are!  The  MISSING  LINK  extension.  This  is just the
unregistered version of  the  extension.  Unfortunately  for  TOP NOTCH
SOFTWARE, not many people registered  for  the  MISTY extension, and so
they decided to put 'one or  two'  limits on the extension. Firstly, an
annoying message appears every now  and  then  telling you to register!
Secondly, none of the compiled versions  of the commands work! Once you
register, you get the correct extensions.

So, the conclusion. The MISSING LINK extension has helped to boost STOS
even further into  the  world  of  high-quality  games. Virtually every
command is  'useful'  and  can  be  used  to  extend  the  programmer's
abilities. Each command is either faster,  smoother, simpler, or just a
damn sight better than their STOS counterparts, and the extension is so
big, it has to come in two parts!

Unfortunately, there are a few  black  linings  to the silver cloud (??
hang on!) The annoying  thing  is,  that  when  entering any text, like
filenames, you  cannot  enter  them  directly  (eg.  BLOAD "STOS.DAT").
Instead, you have to set up a string containing the text or filename or
whatever, add a terminator (!)  at  the  end,  namely CHR$(0), and then
find the address of the text using the VARPTR command! So, here are two
versions to compare:

Normal:  BLOAD "STOS.DAT"
Link:    F$="STOS.DAT"+chr$(0)
         DLOAD varptr(F$) etc etc...

Oh well...I  suppose  there  IS  a  price  to  pay  for  such excellent
commands. Another problem that existed in  the MISTY extension, is that
whenever you copy graphics  either  DOWN  or  RIGHT, instead of getting
just the one copy, the whole screen fills with them!!! Never mind...

On top of all that though,  the  MISSING  LINK extension is superb, and
the attention that was paid to  the  example  programs and games gave a
good idea of what can  be  achieved  with  the  package. I am sure that
there will be some great games springing up soon!

ADDENDUM:

I have just recently received  the  complete  version of the extension.
You get one disk  packed  with  archived  source,  programs, music, and
whatever - and takes up four  disks  when unarchived! The stuff you get
on these disks is amazing - not to mention the 20 extra commands!

Several of these extra  commands  are  similar  to  the world commands,
except they can be used inside a  window and not just the whole screen.
One very useful command is called 'BULLET' and places a small 2x2 pixel
on the screen at a defined  co-ordinate  in  any colour. There are some
more complicated commands, such as the  'MANY' commands. MANY ADD, MANY
SUB, MANY INC, and MANY DEC  are  used  to increase or decrease a whole
list of numbers at the same time, a lot faster than:

for T=1 to 20 : A(T)=A(T)+3 : next T

Here is the MISSING LINK version:

MANY ADD varptr(A(0)),varptr(V(0)),20,0,200

The array V() holds the numbers to add, 20 is the number of elements, 0
is the lowest number,  and  200  is  the  heighest  number. If MANY ADD
increases a number over 200, it returns to 0 (or whatever you specify!)

MANY BOB and MANY JOEY  are  similar  to  BOB  and JOEY except they are
used, as above, to draw out lots of sprites in one go. Just to show the
complexity and flexibility  of  the  MANY  JOEY  command,  here  is the
syntax:

MANY JOEY scr,gadr,imgadr,xadr,yadr,statadr,coladr,xoff,yoff,num,0

MANY BULLET is a cross between MANY  JOEY  and BULLET. So is MANY SPOT.
This next command has to be the longest  of them all. It is called MANY
OVERLAP and has 13 parameters!

r=MANY OVERLAP(x1,y1,xadr,yadr,wid1,hig1,wid2,hig2,statadr,imgadr,
               stval,imgval,num)

It is used to check lots of  coordinates to see if some overlap. =HERTZ
and SET HERTZ are used to read  or set the frequency. RASTER is similar
to PALSPLIT, except it only  splits  one  colour, making it simpler and
faster than PALSPLIT. Finally,  a  command  called MOSTLY HARMLESS rids
STOS of the registration message!

To conclude yet again, it is well  worth  the 10 pounds to register and
receive an update!

Article: BLACK EAGLE 31/5/93