Who invented the border removal techniques ?

[ggn]

As far as i know original members of Factor 5 were previously members of The Light Circle (which was mostly a hacking crew by the way).

Anyone got any prods by them?

George

[Mug UK]

They were an Amiga demo crew as I remember?

Factor 5 was the main development team for Rainbow Arts if memory serves .. or at least almost all their output was released by them anyway.

e.g. a quick google shows some intros released onto a compilation disk (now where have we seen that before?)

• - Copys Disk 1/The Light Circle
  - Demo 1987/The Light Circle
  - Intro/The Light Cricle
  - Intro A500 No/The Light Circle

http://hol.abime.net/search.php?&af=B&N ... eloper=216

And the Factor 5 homepage: http://www.factor5.com/

You can download original master disk images of Turrican 1, 2 & 3 from their "backups" section (with the copy protection intact!) to replace your knackered originals. No sign of any Atari info though

[ggn]

You can download original master disk images of Turrican 1, 2 & 3 from their "backups" section (with the copy protection intact!) to replace your knackered originals. No sign of any Atari info though

Yes, I've seen this bit for a couple of years now. Are they too ashamed to claim the ST versions? Perhaps it's time to send them some e-mails?

George

[mcoder]

check

http://codercorner.com/fullscrn.txt

this should explain quite a bit

Shw

The inventors of the fullscreen were Omega, but they released their demo too late.

The border removals trick come from the Commodore 64, where you have to change the frequency (50/60hz) to fake the video component, and at this moment, the hardware sprites are displayed.
It's the very same trick for the Atari.

JC

[mcoder]

The Ocean game Toki didn't remove any borders at all except until the very end of the game, where it removes all the borders to do a massive full-screen scrolling "game completed" end sequence, which I remember being very surprised at, because the game itself was technically average.

Technically average ?
Are you joking ????

First, it has the best ever sprite routine !
Second, to solve the massive sprites shifting, it preshifts the sprites in advance during the game. In short, the game runs in the VBL routine, and the preshifting out of VBL, and according to the memory left.

The background shifting is terrific too (and very complicated, with partial shiftings, etc...).

Also, there is a packer than decrunches during loading, and if you play, you'll notice that there is never a blank screen.

Most of the things are realtime shifted, and it's quite a miracle.

I guess that if you didn't see anything, it means that the goal of making the game was achieved (technique should disappear behind the game).
Of course, the Amiga coder didn't have to spend efforts on these tricks, allowing to improve the game.

JC

[MiggyMog]

I had played the arcade version before playing the ST version, I thought considering it was an Ocean release it was really impressive. The sound is above average too, right from the intro the sound has a nice buzzer effect. Ivanhoe & Pang were also impresive too.

[AtariFan]

Who invented the border removal tricks ?
- For the upper and lower borders ?
- For the left and rigth borders ?
- How did they get the info about the Shifter's hardware ?

What is the first demo or intro these techniques where used in ?
- Upper and lower borders ?
- Left and rigth borders ?

I found some information in "The history of demo programming on the ST" by Stefan Posthuma (Digital Insanity of The Lost Boys) which might be interesting:

"There was a person named Alyssa associated with TEX for a while but he left after their first demo I believe." [...]

"After 'LCD' (Little Colour Demo), Alyssa discovered how to fool the MMU into opening the lower border. TEX used this technique for the first time in their "NeoChrome Picture Slide Show" which had "NeoChrome" pictures occupying the whole screen, and a scrolling message in the lower border."

The text about "The history of demo programming on the ST" was published in "ST News" around 1991 and IMHO explains the historical background of the ST demo scene really nicely.

[evil]

Who invented the border removal tricks ?
What is the first demo or intro these techniques where used in ?

Hello,

this is from my own research, in chronological order:

1. Lower border
- invented by Alyssa
- used by The Exceptions in the Super Neo Demo Show released September, 1987
- pouet.net: http://pouet.net/prod.php?which=29427

2. Right border
- invented by The Exceptions
- used by The Exceptions in the Amiga Demo released March 1988
- pouet.net: http://pouet.net/prod.php?which=11834 (sadly the screenshot is not from the border screen)

3. Upper border
- this is much more uncertain, the earliest I've found is made by XXX-international
- used in the XXX-international demo released July 1988
- pouet.net: http://pouet.net/prod.php?which=11807
- trivia: The very early upper border routines have a few skewed lines at the top, also look at Alpha Flights Captain Fizz cracktro for similar distortion

4. Left border
- invented by the TNT Crew
- used in the Death Of The Left Border demo released sometime in 1988
- pouet.net: http://pouet.net/prod.php?which=29414

5. Fullscreen part 1
- invented by Omega
- used in the Omega demo released december 1988
- pouet.net: http://pouet.net/prod.php?which=26007
- trivia: This fullscreen only works on very few ST's, and even on them sometimes it doesn't work

6. Fullscreen part 2
- invented by Level 16
- used in the Union demo from January 1989
- pouet.net: http://pouet.net/prod.php?which=11060
- trivia: The first fullscreen to work reliable on most/any ST

7. Syncscroller
- invented by The Carebears, Omega and ST Connexion more or less simultanously
- first used in the Cuddly Demos released in April 1989
- pouet.net: http://pouet.net/prod.php?which=3242

8. 4-bit scynscroller
- invented by ST Connexion
- first used in the Punish Your Machine demo released in november 1991
- pouet.net: http://pouet.net/prod.php?which=11806

9. STe 16pixels left border
- invented by DHS
- used in the Tyranny demo (intro part) released in 1993, but was invented back in 1992
- pouet.net: http://pouet.net/prod.php?which=1000
- trivia: A simple trick to remove 16 pixels of the left border on STe, utilizing the shift buffer of the STe hardscroll. Also used in the Octalyser tracker.

10. STe left/right without stabilizer
- invented by DHS
- not yet used (will be in a while)
- trivia: not really a new effect, but it's a faster way of doing overscan on STe shifters. It also lines up to a more even 224 byte linewidth.


If anyone have corrections or additions, please reply

How many games use border removal ?

- Obsession (upper, lower and 16pix left)
- Stardust (upper, lower (320x256))
- Substation (upper, lower (menu))
- Fulltron (tron in fullscreen, four players)
- Utopos (upper, lower)

--
Anders Eriksson
ae@dhs.nu

[simonsunnyboy]

Lethal Xcess - uses fullscreen and syncscroll technique including automatic border removal.

[bullis1]

Hello,
this is from my own research, in chronological order:
...

Very nice info here! Thanks for digging up this thread!

- Obsession (upper, lower and 16pix left)
- Stardust (upper, lower (320x256))
- Substation (upper, lower (menu))
- Fulltron (tron in fullscreen, four players)
- Utopos (upper, lower)

There are many more games to do this. It's difficult to keep track of them all however. For example, I'm pretty sure this one does: http://www.atarilegend.com/games/games_ ... ame_id=526
It's a commercial game too!

[p01]

10. STe left/right without stabilizer
- invented by DHS
- not yet used (will be in a while)
- trivia: not really a new effect, but it's a faster way of doing overscan on STe shifters. It also lines up to a more even 224 byte linewidth.

Do you mind telling a bit about it ? If it needs no stabilizer, how do you know when to trigger the frequency switches ?

[MiggyMog]

For the new one checkout:-

http://www.atari-forum.com/viewtopic.php?f=68&t=9527

[evil]

Do you mind telling a bit about it ? If it needs no stabilizer, how do you know when to trigger the frequency switches ?

I think you misunderstood. The sync-lock is there of course (I'm using timer-a to trigger before the top border).

The stabilizer that's gone is the one on each overscan scanline, eg the hi/low switch at the end of each line. It saves up about 24 cycles (depending how many registers you waste, it can go down to 16c or up to 32c) per scan and gives 224 byte linewidth instead of the oddly 230 byte with a stabilizer.

The screen is centered a little bit more to the left than a stabilizer overscan and it shows the normal 416 pixels per line. When coding STe I see nothing but advantages with it.

--
Anders Eriksson
ae@dhs.nu

[p01]

Ok. I indeed mistook synch lock and stabilizers.

It sounds great. Looking forward to this in action.
OTOH for some effects, the 230 bytes width can be an advantage but, I guess your technique could also produce overscan lines of a not-multiple-of-8 bytes.

[evil]

It sounds great. Looking forward to this in action.
OTOH for some effects, the 230 bytes width can be an advantage but, I guess your technique could also produce overscan lines of a not-multiple-of-8 bytes.

As you might have noticed, the demo is now out, you can find it here: http://pouet.net/prod.php?which=51962

It's no secret how it's done, and it's simple, this is an example-line of code:

Code: Select all

;init
moveq #2,d7 

; overscan line
dcb.w 6,$4e71
move.b d7,$ffff8260.w
move.w d7,$ffff8260.w
dcb.w 90,$4e71
move.w d7,$ffff820a.w
move.b d7,$ffff820a.w
dcb.w 20,$4e71

So one data register wasted and 464 cycles free per line. 224 bytes linewidth, 416 visible pixels per line.


I also forgot one thing in the border-history list, the interrupt-fullscreen by Ziggy!
Argh, stupid me. So here goes an update:

1. Lower border
- invented by Alyssa
- used by The Exceptions in the Super Neo Demo Show released September, 1987
- pouet.net: http://pouet.net/prod.php?which=29427

2. Right border
- invented by The Exceptions
- used by The Exceptions in the Amiga Demo released March 1988
- pouet.net: http://pouet.net/prod.php?which=11834 (sadly the screenshot is not from the border screen)

3. Upper border
- this is much more uncertain, the earliest I've found is made by XXX-international
- used in the XXX-international demo released July 1988
- pouet.net: http://pouet.net/prod.php?which=11807
- trivia: The very early upper border routines have a few skewed lines at the top, also look at Alpha Flights Captain Fizz cracktro for similar distortion

4. Left border
- invented by the TNT Crew
- used in the Death Of The Left Border demo released sometime in 1988
- pouet.net: http://pouet.net/prod.php?which=29414

5. Fullscreen part 1
- invented by Omega
- used in the Omega demo released december 1988
- pouet.net: http://pouet.net/prod.php?which=26007
- trivia: This fullscreen only works on very few ST's, and even on them sometimes it doesn't work

6. Fullscreen part 2
- invented by Level 16
- used in the Union demo from January 1989
- pouet.net: http://pouet.net/prod.php?which=11060
- trivia: The first fullscreen to work reliable on most/any ST

7. Syncscroller
- invented by The Carebears, Omega and ST Connexion more or less simultaneously
- first used in the Cuddly Demos released in April 1989
- pouet.net: http://pouet.net/prod.php?which=3242

8. 4-bit scynscroller
- invented by ST Connexion
- first used in the Punish Your Machine demo released in november 1991
- pouet.net: http://pouet.net/prod.php?which=11806

9. Interrupt fullscreen
- invented by Ziggy Stardust / Overlanders
- first used in the Overlanders multipart in the Froggies Over The Fence demo released in 1993
- pouet.net: http://pouet.net/prod.php?which=8936
- trivia: Flix/Delta Force also wrote about a technique like this a couple of years before the Froggies demo, but as far as I know, nothing came out of it.

10. STe 16pixels left border
- invented by DHS
- used in the Tyranny demo (intro part) released in 1993, but was invented back in 1992
- pouet.net: http://pouet.net/prod.php?which=1000
- trivia: A simple trick to remove 16 pixels of the left border on STe, utilizing the shift buffer of the STe hardscroll. Also used in the Octalyser tracker and Obsession pinball game.

11. STe left/right without stabilizer
- invented by DHS (but likely tested by many more but considered it unstable)
- used in the More Or Less Zero demo released october 2008
- pouet.net: http://pouet.net/prod.php?which=51962
- trivia: not really a new technique, but it's a simplier/faster way of doing overscan on STe shifters. It also lines up to a more even 224 byte linewidth.

[dyno64100]

Over the past last months, I've remade in HTML5/Canvas all the screens that have marked the era of the Atari ST, seen under the angle of overscan, ie all screens that led to progress in these techniques : sync-locking, overscan, fullscreen, sync-scroll, etc...

You can now run all these screens in a web browser : http://aldabase.com/atari-st-fullscreen-demos-history/ (Google Chrome is prefered)

Presently, the only missing technique is STE left/right without stabilizer

[npomarede]

Great remake !

[Ragstaff]

Nice work, very interesting to read through that

[Zorro 2]

10. STe 16pixels left border
- invented by DHS
- used in the Tyranny demo (intro part) released in 1993, but was invented back in 1992
- pouet.net: http://pouet.net/prod.php?which=1000
- trivia: A simple trick to remove 16 pixels of the left border on STe, utilizing the shift buffer of the STe hardscroll. Also used in the Octalyser tracker and Obsession pinball game.

... and re-used in 2009

[Zorro 2]

A mix of effects : Lower border + Upper border + Syncscroller + Rasters + Plasma



Not in full of course

I think I'm the only one who did it on Atari ST... and it exists one similar screen on Amiga.

[junosix]

Fantastic remake, loved the descriptions. Never realised the first demo with upper border removal originated from my home town!

[mbricout]

Over the past last months, I've remade in HTML5/Canvas all the screens that have marked the era of the Atari ST, seen under the angle of overscan, ie all screens that led to progress in these techniques : sync-locking, overscan, fullscreen, sync-scroll, etc...

You can now run all these screens in a web browser : http://aldabase.com/atari-st-fullscreen-demos-history/ (Google Chrome is prefered)

Presently, the only missing technique is STE left/right without stabilizer

Thank you for your great job illustrating the history of overscan. I can't believe that it was over 12 years ago that I posted that question and started this thread!