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Timing engine: per-note tempo lookup for ms->PPQ conversion #3

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Merged
wretcher207 merged 1 commit into from
Jun 17, 2026
Merged

Timing engine: per-note tempo lookup for ms->PPQ conversion #3

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25 changes: 18 additions & 7 deletions Scripts/dehumanizer-pro.lua
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Original file line number Diff line number Diff line change
Expand Up @@ -267,13 +267,20 @@ end

-- ================= TIMING ENGINE =================

-- Convert a millisecond offset, evaluated at ppq_pos, into a PPQ delta that
-- respects project tempo automation. The old apply_timing derived a single
-- ppq_per_ms ratio from Master_GetTempo() and reused it for every note,
-- which is wrong as soon as the project has tempo changes mid-item.
-- Round-tripping through project time is the only way to stay accurate
-- across tempo curves. Costs 2 API calls per note (APPLY-time only).
local function ms_offset_to_ppq(take, ppq_pos, offset_ms)
local t_sec = reaper.MIDI_GetProjTimeFromPPQPos(take, ppq_pos)
local target_ppq = reaper.MIDI_GetPPQPosFromProjTime(take, t_sec + offset_ms * 0.001)
return target_ppq - ppq_pos
end

local function apply_timing(take, notes, timing_settings, timing_var_curve)
local bpm = reaper.Master_GetTempo()
local ms_per_beat = 60000.0 / bpm
local ppq_per_beat = reaper.MIDI_GetPPQPosFromProjQN(take, 1) -
reaper.MIDI_GetPPQPosFromProjQN(take, 0)
local ppq_per_ms = ppq_per_beat / ms_per_beat
local pitch_role = build_pitch_role_lookup()
local pitch_role = build_pitch_role_lookup()

-- Compute min/max PPQ from notes for normalized phrase position
local min_p, max_p = math.huge, 0
Expand Down Expand Up @@ -302,7 +309,11 @@ local function apply_timing(take, notes, timing_settings, timing_var_curve)
local frac = n.qn - math.floor(n.qn)
local on_beat = (frac < 0.1 or frac > 0.9)
local eff_var = scaled_variance * (on_beat and 0.3 or 1.0)
local offset_ppq = biased_rand_timing(ts.lean_ms, eff_var) * ppq_per_ms
-- Per-note tempo lookup. Note duration is preserved in PPQ, which
-- keeps musical-grid duration even across a tempo change inside the
-- note. Only the start gets the per-note ms->PPQ adjustment.
local offset_ms = biased_rand_timing(ts.lean_ms, eff_var)
local offset_ppq = ms_offset_to_ppq(take, n.ppq, offset_ms)
local new_start = math.max(0, n.ppq + offset_ppq)
n.new_ppq = new_start
n.new_endppq = new_start + (n.endppq - n.ppq)
Expand Down
25 changes: 18 additions & 7 deletions dehumanizer-pro.lua
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -267,13 +267,20 @@ end

-- ================= TIMING ENGINE =================

-- Convert a millisecond offset, evaluated at ppq_pos, into a PPQ delta that
-- respects project tempo automation. The old apply_timing derived a single
-- ppq_per_ms ratio from Master_GetTempo() and reused it for every note,
-- which is wrong as soon as the project has tempo changes mid-item.
-- Round-tripping through project time is the only way to stay accurate
-- across tempo curves. Costs 2 API calls per note (APPLY-time only).
local function ms_offset_to_ppq(take, ppq_pos, offset_ms)
local t_sec = reaper.MIDI_GetProjTimeFromPPQPos(take, ppq_pos)
local target_ppq = reaper.MIDI_GetPPQPosFromProjTime(take, t_sec + offset_ms * 0.001)
return target_ppq - ppq_pos
end

local function apply_timing(take, notes, timing_settings, timing_var_curve)
local bpm = reaper.Master_GetTempo()
local ms_per_beat = 60000.0 / bpm
local ppq_per_beat = reaper.MIDI_GetPPQPosFromProjQN(take, 1) -
reaper.MIDI_GetPPQPosFromProjQN(take, 0)
local ppq_per_ms = ppq_per_beat / ms_per_beat
local pitch_role = build_pitch_role_lookup()
local pitch_role = build_pitch_role_lookup()

-- Compute min/max PPQ from notes for normalized phrase position
local min_p, max_p = math.huge, 0
Expand Down Expand Up @@ -302,7 +309,11 @@ local function apply_timing(take, notes, timing_settings, timing_var_curve)
local frac = n.qn - math.floor(n.qn)
local on_beat = (frac < 0.1 or frac > 0.9)
local eff_var = scaled_variance * (on_beat and 0.3 or 1.0)
local offset_ppq = biased_rand_timing(ts.lean_ms, eff_var) * ppq_per_ms
-- Per-note tempo lookup. Note duration is preserved in PPQ, which
-- keeps musical-grid duration even across a tempo change inside the
-- note. Only the start gets the per-note ms->PPQ adjustment.
local offset_ms = biased_rand_timing(ts.lean_ms, eff_var)
local offset_ppq = ms_offset_to_ppq(take, n.ppq, offset_ms)
local new_start = math.max(0, n.ppq + offset_ppq)
n.new_ppq = new_start
n.new_endppq = new_start + (n.endppq - n.ppq)
Expand Down