The Amazing Demo (Atari ST)

If I recall the dim and distant past I think I wrote this because I was in a bit of a huff with the other members of the Inner Circle and wanted to show I could code something from scratch rather than just "ripping other peoples routs". IIRC this was after the release of the Inner Circle Decade Demo. The joys of teenage angst ;-)

The music was by Mad Max of the Exceptions (ripping music was fairly common in the demo/intro world as there where not that many musicians about).

It was fairly tight code, the wibbly logo was taking advantage of the movep instructions ability to do 8 pixel wide columns on the 16 pixel plane boundry. The overscan in the bottom was quite cool at the time although it was post the fullscreen demo.

Category:

Entertainment

Tags:

• atari
• atari st
• demo
• demo scene
• stsquad
• emulation
• hatari

[stsquad1]

@rastansaga360: The movep was for the vertical distorting logo. The slippy one in the border was a plain old pre-shifted logo with a raster bar zipping through the middle.

[thecoast47]

Good job man.

I have some questions though.

What language did you use?

Did you use a graphics library?

Did you have to write code in an assembler?

[stsquad1]

@thecoast47 The demo was all written in 68k assembler (using the rather nice DevPac Macro Assembler). The graphics routines where all written from scratch although IIRC we (ST Squad Demo Crew) had a demo library for common initialisation functions (enter super-user mode, set-up screens etc).

[stsquad1]

@thecoast47

Most demos on the ST where written in assembler as it was the only way to get the most out of the hardware. I did own a copy of Lattice C but is was a fairly exotic thing to code in at the time. It wasn't overly scary at the time though, the assembler generated a simple executable that you could start from the GUI. You made a few TOS calls to get the initial control of the system but after that you basically "owned" the hardware and could do what you wanted.

[stsquad1]

@thecoast47 Apologies for the multiple posts, comments are limited in size.

The one bit that wasn't assembler is the waveform generation. I had written a utility program in GFA Basic to compute the waveforms. They were then exported as a table of assembler which was linked into the final demo.

[stsquad1]

@rastansaga360 The movep was for the vertical dist logo which was broken into 8 pixel slices. The logo at the bottom was just a plain old pre-shifted movem logo with a raster line going through the middle.