A Commodore 64 Ultimate demo that generates a Mandelbrot fractal on-device at 64 MHz turbo, packs it directly into Upic format (a 16-color, 384x256 border-color raster picture technique), displays it live as it renders, and lets you interactively pan around and zoom into any region of the result.
Requirements
- Ultimate 64 Elite 2 with firmware 3.15 or newer (the corresponding firmware for the original Ultimate 64 board has not been released yet)
Installation
- Extract the ZIP to the root of an SD card or USB drive. The ZIP contains the idi8b/mandelupic/ folder, including both mandelupic.prg and its matching mandelupic.cfg -- extracting at the drive root creates the correct layout.
- In the Ultimate menu, navigate to idi8b/mandelupic/ and run mandelupic.prg. The bundled .cfg auto-loads alongside it and enables the Command Interface and U64 turbo registers this demo needs.
Controls
Generation starts automatically and the picture builds up live. Once complete, you're in browse mode:
| Input | Action |
|---|---|
| W/A/S/D or cursor keys | Pan the current view |
| Z | Enter box mode to pick a zoom target |
| O | Zoom out one notch, clamped to the original overview |
| C | Cycle the base color gradient (sunset, fire, amethyst, rainbow) |
In box mode, four corner markers outline a movable, resizable selection box (W/A/S/D to move, +/- to resize, RETURN to confirm and zoom in, Z to cancel).
There is no quit key -- reset or power off to exit.
Credits
- Code: Xander Mol
- Upic border-color raster technique: Aleksi Eeben
- Fixed-point algorithm design: inspired by 0x444454's mandelbr8 project (documented approach only; no code from that project is used)
- Compiler: Oscar64 by drmortalwombat
- Ultimate 64 hardware: designed by Gideon Zweijtzer / Gideon's Logic
Licensed under the GNU General Public License v3.0.