Was experimenting with hi-res animations on the Apple II.
You generally don't have enough RAM or memory bandwidth to do full-screen
redraws, but you can get some nice effects with limited animation like
this.
There are 8 frames of animation. Only two full frames are ZX02 encoded
(one for each page) and the other frames are drawn by just drawing
the differences (I have a tool that can generate these differences
between PNG files).
The code is not optimized at all, but currently the graphics are roughly
10k total and the music+player is around 6k.
Video
Capture from the AppleWin emulator. Haven't had time to run on real
hardware. On real hardware the music will probably sound a bit worse,
but I am using an "improved" version of my pt3 player which might help
a bit.
System Requirements
Apple II. You need 64k and a Mockingboard if you want sound.
Should work on II+/IIe/IIc/IIgs (though only tested
in various emulators)
Keypresses
Pressing 'O' or 'G' will change the graphics palette to
Orange or Green. (It does this the slow way of
setting/removing the high bits on both pages.
On a IIe you could do the trick of flipping ANN3,
I did that by accident when developing which made me want
to try)
Pressing '+' or '-' will change the frame delay. The original
animation was at 12.5Hz (4 frames of 50Hz music) but
it actually can draw faster than that.
Graphics: based on an animation by @redlot_to on twitter
Music: "Intro Theme" by Alex Rostov
Fast disk code: qkumba
Run it in Your Browser
Try it out at the internet archive here:
star_lady
Development Notes
V1.0 notes -- 15 November 2025
Wasn't supposed to be working on this, was supposed to be grading papers.
However when an idea gets in my head I sort of have to implement it so
I can move on.
This was all relatively straightforward and opens the idea of doing
similar animations in a later demoscene demo. I was surprised how
nicely it turned out, it's always fun seeing an Apple II turning
into a party machine.