open any vocal synth file ever made

so you know how the TODO said “MIDI file import” as one little checkbox? I may have slightly exceeded scope on that one.

UTAU.js can now import UST, USTX, VPR, VSQX, VSQ, SVP, MIDI, MusicXML, PPSF, S5P, TSSLN, CCS, DV, and UFData files. that’s UTAU, OpenUTAU, Vocaloid, Synthesizer V, Piapro Studio, CeVIO, DeepVocal, and standard MIDI. basically every vocal synth format that exists.

this is thanks to utaformatix-ts by sevenc-nanashi, which is a universal parser for vocal synth project files. it converts everything into a common UfData format. I wrote a 145-line adapter (ufdata.ts) that converts UfData into UTAU.js Scores. lazy-loaded so the parser only gets pulled in when you actually import a file.

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pitch bends

this was the hard part. vocal synth files have pitch curves. track-level arrays of tick-value pairs that describe how the pitch deviates from the written note. the importer splits the track-level curve into per-note pitch bends, handling absolute-to-relative conversion, null value filtering, start/end padding, and extrapolation from preceding points.

the renderer now reads note.pitchBend and interpolates it per-sample alongside vibrato. the math: f0 = baseF0 * 2^((bendSemitones * 100 + vibratoCents) / 1200). pitch bends and vibrato stack correctly in cents space.

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piano roll overhaul

the piano roll was hardcoded to 3 octaves (ik bad, but will fix soon) and a fixed width. now it covers the full MIDI range (0-127) with virtual scrolling. wheel scrolls vertically, shift+wheel or trackpad scrolls horizontally. viewport culling so only visible notes and key labels get drawn. auto-scrolls to center on notes when you import a file.

also: pitch curves render as yellow lines overlaid on note blocks. you can see the imported pitch data right there on the piano roll.

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other stuff

added await setTimeout(0) in the streaming loop so the UI doesn’t freeze during long scores. the demo has an “Open” button that accepts all 14 supported file extensions. TODO got updated with a lot of checkboxes ticked.

Some amount of lines of import tests covering note mapping, tempo conversion, pitch splitting (absolute, relative, null filtering, extrapolation, out-of-range skipping, pitch:false opt-out), and edge cases.