Amiga500 40k intro. Created with vscode-amiga-debug by bartman/abyss
https://www.pouet.net/prod.php?which=95887
release name: Soil
type: Amiga 500 - 40k intro
release date: 19.01.2024
code + music: Virgill
gfx: Critikill
Amiga ASCII: NE7
rendering worlds, needs +512k to run
Contact us @ PLK 555-NASE
I (Virgill) embarked on a delightful
8-week journey rekindling my coding
skills on the Amiga. After a whopping 33
years, my mind was practically a blank
slate. It all began when I pondered if a
routine, akin to my Windows 4k intro
"Xorverse," could somehow find a home on
the Amiga. Excited, I fired up the
fantastic VScode-Amiga-debug environment
from Abyss, only to hit a snag - the
good old Amiga could only handle
rendering a maximum of 2 lines of
graphics for those xor algorithms per
frame.
Undeterred, I decided scrolling could be
a solution, and that's when the real
challenges surfaced. How on earth do I
create a copperlist? What's the secret
to waiting for the beam in the lower
part of the screen? And how in the world
do I turn the graphics upside down? Ah,
there's a modulo register; let's just
brute force it until it looks good.
Thinking I could turn this into a
complete intro, I needed a music player.
Choosing Aklang and LSP seemed like a
no-brainer, but boy, it gave me more
grey hairs than I anticipated. Shoutout
to Platon42 and Leonard for coming to my
rescue, helping me run it smoothly. And
yes, I even had to dabble in assembler
to coax a beat counter out of LSP,
bringing back the basics of 68000
assembly.
Next up on the list: sprites. It
couldn't be that hard, right? Wrong!
Creating data structures for sprites
turned out to be a headache, courtesy of
Commodore. I longed for the simplicity
of the C64. Still, I somehow managed to
showcase a spaceship, invaders, and a
border.
Enter Critikill, whose involvement
injected new life into the project. His
fantastic graphics and assets became a
tremendous source of inspiration. Thanks
a bunch, mate!
Now, it was time to tackle the blitter,
a step that filled me with awe.
Brute-forcing blitter minterms
(resulting in the fire-fx) was the
initial approach until Leonard
enlightened me on an easier way to
calculate them. Blitting those bubbles
ensued, discovering the comfort of
interleaved bitplanes mode. One blit per
bubble – how comfy! Crafting the
copperlist for those looping bitplanes
in two speeds took a week of logic.
Blitting over the repeating bitplane
borders? Another week :)
The sine part threw another challenge my
way. In C, plotting many dots wasn't
feasible, so back to asm it was. Speed
increased, but occasional jerky frame
drops persisted. Thanks to Platon for
the hint on the CIA player and how to
fix the waitVBL routine!
I could share more, like the
satisfaction when a simple fade routine
finally worked, or the art of filling
the remaining 4k with a speech sample
when coding fatigue set in.
Major kudos to the insane Amiga coders
who've mastered every bit and trick in
this machine. It's downright crazy hard!
Special thanks to:
Soundy for the quick gradientmaster
update.
Magic for testing on real hardware.
Nosferatu, Platon, Dan, Ok3anos for
helpful tips.
Noname, Hellfire, Artlace, and possibly
others I forgot – you know who you are!