MDP — MusicDiscPlayer, JavaScript port
A pixel-exact browser recreation of MDP.EXE, the S3M/MOD player and music-disk engine by
Future Crew (1993). One site, a launcher to pick the disc, then the original menu and playing screen
at the original 640x480.
| Disc | Player | Content |
|---|
journey1 | MDP v1.0 | Journey I, Purple Motion |
journey2 | MDP v1.0 | Journey II, Purple Motion |
chmind | MDP v1.1 | Chaotic Mind, Skaven (adds +/- volume, S mono/stereo) |
The original files stay untouched in their folders.
Run
tools/build.sh dist && python3 -m http.server -d dist 8000
Open http://localhost:8000/. Pushes to main deploy to GitHub Pages (.github/workflows/pages.yml).
Mouse: wheel scrolls the menu (volume on the playing screen, with Shift: order), click selects then plays, click the progress bar to seek, click "ESC for menu" / "F10 for dos". Back button or Backspace: playing screen to menu, menu to launcher.
CRT option (display only, off by default; checkbox or C, remembered): a scanline + faint vignette overlay. The picture is then sized to a whole number k of device pixels per source row (k*480 px high) so the bands are regular, with no moire; unavailable (checkbox greyed) when k < 2.
Your own music: the launcher has a "Your own music" entry (disc.html?d=upload): pick or drop any module libopenmpt loads (MOD S3M XM IT 669 AMF AMS DBM DMF DSM FAR MDL MED MTM OKT PTM STM ULT UMX MT2 PSM ...; not libmodplug's ABC/MIDI/PAT) and it plays on the original playing screen with the same controls. The file stays in the browser. S3M and standard MODs use the exact parser; other formats get their note markers from libopenmpt's pattern data (sample volume/loop and slides are not followed, so the markers are approximate).
Keys: arrows / PgUp / PgDn and Enter in the menu; Esc switches between menu and playing screen, F10 leaves;
Left/Right change order; +/- volume and S stereo on Chaotic Mind; Space pauses. Under the canvas: pause,
seek bar and a Hi-fi / Old-school sound switch.
How faithful is it
- Menu and screens: ported line by line from the original assembly onto a 4-plane framebuffer, so pixels
match. The menu is checked on every vsync frame against the original code running in an emulator
(
tools/oracle.py, tools/tests/menu_vs_oracle.mjs). The v1.1 menu and the playing screen's static parts match
DOSBox-X captures with 0 differing pixels.
- Audio: libopenmpt (WebAssembly). Hi-fi: sinc interpolation. Old-school: 22.05 kHz, no interpolation, 8-bit.
- Not exact: the markers are shifted up 3 octaves (no pile-up on the bottom row). The coloured note markers are rebuilt from pattern data (the original read STMIK's channel state), so
slides and vibrato do not move them. The progress bar and positions come from libopenmpt.
Layout
| Path | Content |
|---|
site/ | The web app (js/menu.js, text.js, play.js, vga.js, tracker.js, audio worklet), writeup.html |
tools/ | Emulator oracle, disassembler helper, DOSBox-X capture scripts, tests, build.sh |
docs/ANALYSIS.md | Reverse-engineering notes |
work/ | Disassembly dumps and the unpacked v1.0 EXE |
Credits and rights
All content belongs to its authors: MDP, Future Crew; music, Purple Motion and Skaven; sound engine STMIK, Sami
Tammilehto; libopenmpt, the OpenMPT project (see site/vendor). Preservation and educational port.
