impl S6x and Wxx cmd

TAUD_NOTE_EFFECTS.md

@@ -666,7 +666,17 @@ ProTracker `E5x` maps to Taud `S $2x00` with the same index meaning.
 
 **Compatibility.** IT `S6x` maps directly.
 
-**Implementation.** TODO
+**Implementation.** Maintain a per-row accumulator `fine_delay_extra` on the tracker state, initialised to 0 at the start of every row parse (including pattern-delay repetitions caused by S $Ex). Each S $6x command encountered during the row scan adds `$x` to `fine_delay_extra`. The row then runs for `speed + fine_delay_extra` ticks instead of the usual `speed` ticks before advancing to the next row.
+
+```
+on row parse (S $6x):
+    fine_delay_extra += x       # sum across all channels
+
+row ends when:
+    tick_in_row >= ticks_per_row + fine_delay_extra
+```
+
+S $6x and S $Ex are orthogonal: when S $Ex is active the current row repeats `$x` additional times, and each repetition is itself extended by `fine_delay_extra` (re-accumulated from the same row's S $6x commands). There is no memory for S $6x; `$x == 0` is a no-op.
 
 ---
 

it2taud.py

@@ -25,7 +25,8 @@ Effect support:
     A-Z dispatch per TAUD_NOTE_EFFECTS.md. IT-specific: Cxx is binary
     (not BCD like ST3). V scales by ×2 (IT 0-128 → Taud 0-255). X is
     the full 8-bit IT pan. Y panbrello nibble-repeats. Z (MIDI macro)
-    dropped. S6x tick-delay dropped. SAx high-offset dropped. S7x NNA /
+    dropped. S6x fine-pattern-delay forwarded directly to Taud S$6x. SAx
+    high-offset dropped. S7x NNA /
     past-note / envelope toggles forwarded directly (IT sub-codes match
     Taud one-to-one). Vol-column pitch-slide / tone-porta / vibrato sub-
     commands forwarded to main effect slot when empty; dropped otherwise.
@@ -45,7 +46,7 @@ from taud_common import (
     PATTERN_ROWS, PATTERN_BYTES, NUM_PATTERNS_MAX, NUM_CUES, CUE_SIZE, NUM_VOICES,
     NOTE_NOP, NOTE_KEYOFF, NOTE_CUT, TAUD_C4,
     TOP_NONE, TOP_A, TOP_B, TOP_C, TOP_D, TOP_E, TOP_F, TOP_G, TOP_H, TOP_I,
-    TOP_J, TOP_K, TOP_L, TOP_O, TOP_Q, TOP_R, TOP_S, TOP_T, TOP_U, TOP_V, TOP_Y,
+    TOP_J, TOP_K, TOP_L, TOP_O, TOP_Q, TOP_R, TOP_S, TOP_T, TOP_U, TOP_V, TOP_W, TOP_Y,
     SEL_SET, SEL_UP, SEL_DOWN, SEL_FINE,
     EFF_A, EFF_B, EFF_C, EFF_D, EFF_E, EFF_F, EFF_G, EFF_H, EFF_I, EFF_J,
     EFF_K, EFF_L, EFF_M, EFF_N, EFF_O, EFF_P, EFF_Q, EFF_R, EFF_S, EFF_T,
@@ -104,7 +105,9 @@ VC_TPORTA_TABLE = (0, 1, 4, 8, 16, 32, 64, 96, 128, 255)
 IT_MEM_EFFECTS = frozenset({
     EFF_D, EFF_E, EFF_F, EFF_G, EFF_H, EFF_I, EFF_J,
     EFF_K, EFF_L, EFF_N, EFF_O, EFF_P, EFF_Q, EFF_R,
-    EFF_S, EFF_T, EFF_U, EFF_V, EFF_W, EFF_X, EFF_Y,
+    EFF_S, EFF_T, EFF_U, EFF_X, EFF_Y,
+    # EFF_V excluded: V00 means literal 0 in IT, not recall.
+    # EFF_W excluded: Taud engine handles W recall natively (same private-slot semantics).
 })
 
 
@@ -784,7 +787,7 @@ def encode_effect_it(cmd: int, arg: int, ch: int = 0, row: int = 0,
       - Cxx: binary row number, not BCD
       - V: IT global vol 0-128 scaled ×2
       - X: IT full 8-bit pan → 6-bit
-      - S6x, S7x, SAx, SFx handled (mostly dropped)
+      - S6x: fine pattern delay forwarded; S7x forwarded; SAx/SFx dropped
 
     amiga_mode mirrors the inverse of the IT ``linear_slides`` flag.  When
     set, E/F coarse pitch-slide arguments are emitted as raw IT period units
@@ -877,8 +880,8 @@ def encode_effect_it(cmd: int, arg: int, ch: int = 0, row: int = 0,
             pan8 = (val << 4) | val
             return (TOP_S, 0x8000 | pan8, None, None)
         if sub == 0x6:
-            vprint(f"    dropped S6{val:X} (tick delay) at ch{ch} row{row}")
+            # IT S6x = fine pattern delay (extends row by x ticks) — maps directly.
-            return (TOP_NONE, 0, None, None)
+            return (TOP_S, 0x6000 | (val << 8), None, None)
         if sub == 0x7:
             # NNA / past-note / envelope on-off — IT S7x maps directly to Taud S $7x00
             # (same sub-code table). No payload to translate.
@@ -904,8 +907,8 @@ def encode_effect_it(cmd: int, arg: int, ch: int = 0, row: int = 0,
         return (TOP_V, (taud_v & 0xFF) << 8, None, None)
 
     if cmd == EFF_W:
-        vprint(f"    dropped W{arg:02X} (global vol slide) at ch{ch} row{row}")
+        # W$xy: same nibble-pair layout as D, passed in the high byte.
-        return (TOP_NONE, 0, None, None)
+        return (TOP_W, (arg & 0xFF) << 8, None, None)
 
     if cmd == EFF_X:
         return (TOP_S, 0x8000 | (arg & 0xFF), None, None)
@@ -926,8 +929,7 @@ def encode_effect_it(cmd: int, arg: int, ch: int = 0, row: int = 0,
 
 def resolve_it_recalls(patterns_rows: list, order_list: list,
                        num_channels: int, link_gef: bool,
-                       old_effects: bool = False,
+                       old_effects: bool = False) -> None:
-                       initial_global_vol: int = 128) -> None:
     """Walk in order, resolve zero-arg recalls per-effect-per-channel.
 
     IT effect memory groups:
@@ -940,14 +942,13 @@ def resolve_it_recalls(patterns_rows: list, order_list: list,
     they do NOT recall and are suppressed to TOP_NONE. All other effects
     still recall normally even in old_effects mode.
 
-    V memory is primed with initial_global_vol so a song-leading V $0000
+    V and W are excluded from IT_MEM_EFFECTS and are not resolved here:
-    resolves to the header's global volume, not literal zero.
+    V00 in IT means literal 0 (not recall); W recall is handled natively
+    by the Taud engine's private W memory slot.
     """
     # last_mem[ch][eff_key] = last_non_zero_arg
     # eff_key: integer 1-26 for most effects; we merge cohorts by normalising.
     last_mem = [{} for _ in range(num_channels)]
-    for ch in range(num_channels):
-        last_mem[ch][EFF_V] = initial_global_vol
 
     # Effects that stop rather than recall when arg=0 in old_effects mode (ST3 compat).
     # E/F: pitch slide stop. J: arpeggio stop (J00 = return to normal pitch in ST3).
@@ -1487,8 +1488,7 @@ def assemble_taud(h: ITHeader, samples: list, instruments: list,
     # ── Resolve IT recalls ───────────────────────────────────────────────────
     vprint("  resolving IT recalls…")
     resolve_it_recalls(patterns_rows, h.order_list, 64, h.link_gef,
-                       old_effects=h.old_effects,
+                       old_effects=h.old_effects)
-                       initial_global_vol=h.global_vol)
 
     init_speed, _ = find_initial_bpm_speed(patterns_rows, h.order_list,
                                            h.initial_speed, h.initial_tempo)

s3m2taud.py

@@ -17,8 +17,9 @@ Effect support:
     table" and "ScreamTracker 3 conversion notes". ST3 shared-memory recalls
     (D/E/F/I/J/K/L/Q/R/S with $00 arg) are eagerly resolved per channel.
     Cxx is BCD-decoded. K/L are split into H $0000 / G $0000 + volume-column
-    slide. M/N/X/P fold into volume / pan columns. W (global vol slide) is
+    slide. M/N/X/P fold into volume / pan columns. W (global vol slide)
-    dropped with a -v warning. X converts to pan column. Y (panbrello) converts
+    converts to Taud W (arg in high byte, same encoding as D). X converts to
+    pan column. Y (panbrello) converts
     to Taud Y. S5 selects the panbrello LFO waveform. S8x converts to a pan
     column SET of round(x * 4.2), mapping nibble 0-15 directly to pan 0-63.
 """
@@ -36,7 +37,7 @@ from taud_common import (
     PATTERN_ROWS, PATTERN_BYTES, NUM_PATTERNS_MAX, NUM_CUES, CUE_SIZE, NUM_VOICES,
     NOTE_NOP, NOTE_KEYOFF, NOTE_CUT, TAUD_C4,
     TOP_NONE, TOP_A, TOP_B, TOP_C, TOP_D, TOP_E, TOP_F, TOP_G, TOP_H, TOP_I,
-    TOP_J, TOP_K, TOP_L, TOP_O, TOP_Q, TOP_R, TOP_S, TOP_T, TOP_U, TOP_V, TOP_Y,
+    TOP_J, TOP_K, TOP_L, TOP_O, TOP_Q, TOP_R, TOP_S, TOP_T, TOP_U, TOP_V, TOP_W, TOP_Y,
     SEL_SET, SEL_UP, SEL_DOWN, SEL_FINE,
     EFF_A, EFF_B, EFF_C, EFF_D, EFF_E, EFF_F, EFF_G, EFF_H, EFF_I, EFF_J,
     EFF_K, EFF_L, EFF_M, EFF_N, EFF_O, EFF_P, EFF_Q, EFF_R, EFF_S, EFF_T,
@@ -356,8 +357,8 @@ def encode_effect(cmd: int, arg: int, ch: int = 0, row: int = 0,
         return (TOP_V, (min(arg * 4, 0xFF) & 0xFF) << 8, None, None)
 
     if cmd == EFF_W:
-        vprint(f"    dropped W{arg:02X} (global vol slide) at ch{ch} row{row}")
+        # W$xy: same nibble-pair layout as D, passed in the high byte.
-        return (TOP_NONE, 0, None, None)
+        return (TOP_W, (arg & 0xFF) << 8, None, None)
 
     if cmd == EFF_X:
         return (TOP_S, 0x8000 | (arg & 0xFF), None, None)

taud_common.py

@@ -67,6 +67,7 @@ TOP_S    = 0x1C
 TOP_T    = 0x1D
 TOP_U    = 0x1E
 TOP_V    = 0x1F
+TOP_W    = 0x20
 TOP_Y    = 0x22
 
 # Volume / pan column selectors (2-bit field at top of vol/pan byte)

terranmon.txt

@@ -2093,8 +2093,8 @@ TODO:
     [x] on playback, panning changes randomly on Taud made by s3m2taud.py and mod2taud.py, but not by it2taud.py (maybe something's off with the instrument exports?)
     [x] NNA not disabled for S3M and MOD
     [x] `S B000` and `S B100` not working as intended -- on first playback it jumps to the next cue same row, on subsequent playbacks the commands are completely ignored
-    [ ] implement S6x command
+    [x] implement S6x command
-    [ ] implement Wxx command (global volume slide)
+    [x] implement Wxx command (global volume slide)
     [ ] implement sample loop sustain
     [ ] cue and pattern compression of the Taud format (taud_common.py, taud.mjs)
     [ ] figure out how IT (8 bits) and FT2 (12 bits) handles volume fadeout numbers, and come up with a compatible Taud spec, then implement

tsvm_core/src/net/torvald/tsvm/peripheral/AudioAdapter.kt

@@ -1679,6 +1679,7 @@ class AudioAdapter(val vm: VM) : PeriBase(VM.PERITYPE_SOUND) {
         val cue = cueSheet[ts.cuePos]
         // Reset row-scope state before scanning channels.
         if (!ts.patternDelayActive) ts.sexWinningChannel = -1
+        ts.finePatternDelayExtra = 0
 
         for (vi in 0..19) {
             val patNum = cue.patterns[vi]
@@ -1699,6 +1700,7 @@ class AudioAdapter(val vm: VM) : PeriBase(VM.PERITYPE_SOUND) {
             voice.panbrelloActive = false
             voice.retrigActive = false
             voice.tempoSlideDir = 0
+            voice.wSlideDir = 0
             voice.volColSlideUp = 0; voice.volColSlideDown = 0
             voice.panColSlideRight = 0; voice.panColSlideLeft = 0
             voice.rowEffect = row.effect
@@ -1885,6 +1887,19 @@ class AudioAdapter(val vm: VM) : PeriBase(VM.PERITYPE_SOUND) {
                 val hi = (rawArg ushr 8) and 0xFF
                 playhead.globalVolume = hi
             }
+            EffectOp.OP_W -> {
+                val arg = resolveArg(rawArg, voice.mem.w).also { if (rawArg != 0) voice.mem.w = it }
+                val hi = (arg ushr 8) and 0xFF
+                val lo = hi and 0x0F
+                val hin = (hi ushr 4) and 0x0F
+                when {
+                    hi == 0xFF -> playhead.globalVolume = (playhead.globalVolume + 0xF).coerceAtMost(0xFF)  // WFF quirk: fine up by F
+                    hin == 0xF && lo != 0 -> playhead.globalVolume = (playhead.globalVolume - lo).coerceAtLeast(0)   // fine down on tick 0
+                    lo == 0xF && hin != 0 -> playhead.globalVolume = (playhead.globalVolume + hin).coerceAtMost(0xFF) // fine up on tick 0
+                    hin == 0 && lo != 0 -> { voice.wSlideDir = -1; voice.wSlideAmount = lo }   // coarse down per non-first tick
+                    lo == 0 && hin != 0 -> { voice.wSlideDir = +1; voice.wSlideAmount = hin }  // coarse up per non-first tick
+                }
+            }
             EffectOp.OP_Y -> {
                 val sp = (rawArg ushr 8) and 0xFF
                 val dp = rawArg and 0xFF
@@ -1908,6 +1923,7 @@ class AudioAdapter(val vm: VM) : PeriBase(VM.PERITYPE_SOUND) {
             0x3 -> { voice.vibratoWave = x and 3; voice.vibratoRetrig = (x and 4) == 0 }
             0x4 -> { voice.tremoloWave = x and 3; voice.tremoloRetrig = (x and 4) == 0 }
             0x5 -> { voice.panbrelloWave = x and 3; voice.panbrelloRetrig = (x and 4) == 0 }
+            0x6 -> ts.finePatternDelayExtra += x   // fine pattern delay: accumulate across channels
             0x7 -> when (x) {
                 // Past-note actions on the channel's background ghosts.
                 0x0 -> applyPastNoteAction(ts, vi, 0)   // Past Note Cut
@@ -2142,6 +2158,15 @@ class AudioAdapter(val vm: VM) : PeriBase(VM.PERITYPE_SOUND) {
             }
         }
 
+        // Global volume slide (W coarse) — applied once per non-first tick per armed channel.
+        if (ts.tickInRow > 0) {
+            for (voice in ts.voices) {
+                if (voice.wSlideDir != 0) {
+                    playhead.globalVolume = (playhead.globalVolume + voice.wSlideDir * voice.wSlideAmount).coerceIn(0, 0xFF)
+                }
+            }
+        }
+
         // Funk repeat (S$Fxxxx) — advance bit-mask per tick on instruments with active funkSpeed.
         for (voice in ts.voices) {
             if (voice.funkSpeed == 0 || !voice.active) continue
@@ -2241,7 +2266,7 @@ class AudioAdapter(val vm: VM) : PeriBase(VM.PERITYPE_SOUND) {
                 ts.samplesIntoTick -= spt
                 applyTrackerTick(ts, playhead)
                 ts.tickInRow++
-                if (ts.tickInRow >= playhead.tickRate) {
+                if (ts.tickInRow >= playhead.tickRate + ts.finePatternDelayExtra) {
                     ts.tickInRow = 0
                     advanceRow(ts, playhead)
                 }
@@ -2458,6 +2483,7 @@ class AudioAdapter(val vm: VM) : PeriBase(VM.PERITYPE_SOUND) {
         var o: Int = 0
         var q: Int = 0
         var tslide: Int = 0
+        var w: Int = 0
     }
 
     class Voice {
@@ -2606,6 +2632,10 @@ class AudioAdapter(val vm: VM) : PeriBase(VM.PERITYPE_SOUND) {
         var tempoSlideDir = 0              // 0 = none, -1 = down, +1 = up
         var tempoSlideAmount = 0
 
+        // Global volume slide (W $xy00) — per-channel, applied to playhead.globalVolume on tick > 0.
+        var wSlideDir = 0                  // 0 = none, -1 = down, +1 = up
+        var wSlideAmount = 0
+
         // Volume / pan column slides (selectors 1/2/3 from TAUD_NOTE_EFFECTS.md §"Volume column effects").
         var volColSlideUp = 0
         var volColSlideDown = 0
@@ -2641,6 +2671,9 @@ class AudioAdapter(val vm: VM) : PeriBase(VM.PERITYPE_SOUND) {
         // Channel index of the SEx that won this row (lowest channel wins ties).
         var sexWinningChannel = -1
 
+        // Fine pattern delay (S$6x) — extra ticks added to the current row; accumulated across all channels.
+        var finePatternDelayExtra = 0
+
         // Pre-allocated mix buffers for dither path (reused each audio chunk).
         val mixLeft  = FloatArray(TRACKER_CHUNK)
         val mixRight = FloatArray(TRACKER_CHUNK)
@@ -2764,6 +2797,7 @@ class AudioAdapter(val vm: VM) : PeriBase(VM.PERITYPE_SOUND) {
                 ts.pendingRowJumpLocal = false
                 ts.patternDelayRemaining = 0; ts.patternDelayActive = false
                 ts.sexWinningChannel = -1
+                ts.finePatternDelayExtra = 0
                 ts.panLaw = initialGlobalFlags and 1
                 ts.amigaMode = (initialGlobalFlags and 2) != 0
                 ts.voices.forEach {