The "ScoopZX" intro
So here we go.. this might be a bit lenghty..
I cannot tell how thrilled I was to finally get something completed and released. It has been 19 years I last time competed in a demo competition. For an old horse like me is was nice to get back to my roots, code Z80 on my first love Speccy and actually finish an intro I started in 1988 (the border scroller). The "ScoopZX" intro itself is a bit sucky and short of effects but served me as a proof of getting something done on demo front.
I found several nice and tiny screen captures from zx.pk.ru and shamelessly "borrowed" those.
Some additional information and credits. WayneKerr (our universal hero) came up with the "ScoopZX" name after seeing the first preview a long time ago. Britelite/Dekadence made the cool colorful logo. Wal/Damones made the b&w logo in the model selector screen. ne7/Scx composed the fab music before I could spell a cat. Photon/Scx made the nice font set and raster bars. I somehow managed the rotozooming skull, the isometric logo and the border logo. Background patterns are also "borrowed" by me from somewhere.. Huge thanks to Laesq for fixing me a fully functional and refurbished Spectrum +3 with DiVIDE and a CF! And also serving as my Spectrum +2 testing slave.
Now comes the low-tech part... The "ScoopZX" intro is a single file thing, i.e. everything is in RAM at once. The original binary is 30208 bytes. Spectrum 128K +2/+2A/+3 model is required due to AY and double buffering. Did I mention how much I loathe tweaking timings for different Speccy models, didn't I? Aaargh!
The intro is crunched into one giant BASIC program line using ZXPac (get the C source here and the Z80 decruncher code here). The tap-file creation tool used was ZXTap (get the C source here). Why it was done like this? Just because I always wanted to do one when I was a kid tapping those rubber keys on my 48K Speccy.
All effects run in one frame (of course!) and are done in real-time. To be exact there are about five effects: 1) 48x24 8 color rotozoomer, 2) 4 color isometric logo scroller, 3) 8-pixel granular upper border logo scroller, 4) full screen width raster bars, and 5) DYPP with 27 8x8 pixel masked sprites and free moving background behind the DYPP. The only exception to real-time calculation is the pre-shifted font set.
Anyway, I guess this is getting boring already. I *hope* to come up with more 8-bit / almost 16-bit stuff in the future on some platform that is not C64 ;) Honestly, I don't understand how those guys out there can make such awesome demos on C64, Speccy and Vic-20.. just awesome.
..more coffee..
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