2taud update

it2taud.py

@@ -531,7 +531,7 @@ def parse_instruments(data: bytes, h: ITHeader) -> list:
 
         # Parse IT envelopes (new-format only, ≥cmwt 0x200)
         # Vol envelope at ptr+0x130; pan envelope at ptr+0x182
-        ticks_per_sec = max(h.initial_tempo / 60.0 * h.initial_speed, 1.0)
+        ticks_per_sec = max(h.initial_tempo * 2.0 / 5.0, 1.0)   # tick rate = bpm×2/5 (50 Hz at 125 BPM); speed is ticks-per-row, irrelevant here
         inst.vol_envelope, inst.vol_env_sustain = _parse_it_envelope(
             data, ptr + 0x130, False, ticks_per_sec)
         inst.pan_envelope, inst.pan_env_sustain = _parse_it_envelope(

s3m2taud.py

@@ -624,8 +624,8 @@ def build_sample_inst_bin(instruments: list) -> tuple:
         struct.pack_into('<H', inst_bin, base + 8,  ls)
         struct.pack_into('<H', inst_bin, base + 10, le)
         inst_bin[base + 12] = flags_byte
-        # Volume envelope: hold at instrument volume (vol*4 clamped to 255)
-        env_vol = min(inst.volume * 4, 255)
+        # Volume envelope: hold at instrument volume (clamped to 0x3F)
+        env_vol = min(inst.volume, 63)
         inst_bin[base + 16] = env_vol   # volume
         inst_bin[base + 17] = 0         # offset minifloat = 0 → hold
 

terranmon.txt

@@ -2018,10 +2018,10 @@ Instrument bin: Registry for 256 instruments, formatted as:
     Bit8   Reserved
   Bit16x8 Volume envelopes
        Byte 1: Volume (00..3F)
-       Byte 2: Second offset from the prev point, in 3.5 Unsigned Minifloat
+       Byte 2: Time until the next point, in seconds (3.5 Unsigned Minifloat). 0 = hold at this point indefinitely.
   Bit16x8 Panning envelopes
       Byte 1: Pan (00..FF)
-      Byte 2: Second offset from the prev point, in 3.5 Unsigned Minifloat
+      Byte 2: Time until the next point, in seconds (3.5 Unsigned Minifloat). 0 = hold at this point indefinitely.
   Bit16x8 Reserved
 
 Play Data: play data are series of tracker-like instructions, visualised as: