volume policy when unspecified: retrigger (note+inst cmd) -> default value, no retrigger (note cmd only) -> prev value

assets/disk0/tvdos/bin/taut.js

@@ -1826,8 +1826,10 @@ function simulateRowState(ptnDat, uptoRow) {
         const isGRow = (effop === OP_G)
         const isNoteDelay = (effop === OP_S) && (((effarg >>> 12) & 0xF) === 0xD)
         // Track whether this row reloads the channel's default volume.  Engine:
-        // triggerNote() resets channelVolume to 0x3F on fresh triggers, and an
+        // triggerNote() resets channelVolume to 0x3F only when the row carries an
-        // instrument byte on a tone-porta row also reloads default vol (matches
+        // instrument byte; a note-only retrigger (inst === 0) inherits the
+        // channel's existing volume.  Tone-porta rows follow the same rule —
+        // an instrument byte on a porta row reloads default vol (matches
         // schism csf_instrument_change inst_column branch).
         let reloadDefaultVol = false
         if (note !== 0xFFFF && note !== 0xFFFE) {
@@ -1842,17 +1844,21 @@ function simulateRowState(ptnDat, uptoRow) {
                 lastNote = note
                 pitchOff = 0
                 portaTarget = -1
-                reloadDefaultVol = true
+                if (inst !== 0) reloadDefaultVol = true
             } else {
                 lastNote = note
                 pitchOff = 0
                 portaTarget = -1
-                reloadDefaultVol = true
+                if (inst !== 0) reloadDefaultVol = true
             }
         }
         if (inst !== 0) lastInst = inst
         // Default vol reset must happen before the volume column so a SET selector
         // can still override on the same row (engine order: triggerNote → applyVolColumn).
+        // Pan: simulator does not track per-instrument default pan, so it never resets
+        // panAbs on trigger — this naturally matches the "stay at old value when inst === 0"
+        // half of the policy. The engine-side default-pan reload (gated on inst !== 0)
+        // is invisible here.
         if (reloadDefaultVol) volAbs = 0x3F
 
         // Pre-scan effect column for S$80xx (8-bit pan SET wins over volcol/pancol SET).

terranmon.txt

@@ -2345,7 +2345,7 @@ TODO:
         for LEFT/RIGHT and `shiftPatternArea` for UP/DOWN, plus per-row
         (`drawOrdersRowAt`) and per-column (`drawOrdersVoiceColumnAt`) helpers,
         replacing the full-panel redraw on every keystroke.
-    [ ] volume and panning policy to match note effect policy: when note is "retriggerred" (note command with instrument specified), the volume/pan must take default value; if not (note command with instrument 0) the volume/pan must stay at the old value. Make both audio engine and taut.js simulator changes.
+    [x] volume and panning policy to match note effect policy: when note is "retriggerred" (note command with instrument specified), the volume/pan must take default value; if not (note command with instrument 0) the volume/pan must stay at the old value. Make both audio engine and taut.js simulator changes.
 
 
 Play Data: play data are series of tracker-like instructions, visualised as:

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

@@ -1689,19 +1689,24 @@ class AudioAdapter(val vm: VM) : PeriBase(VM.PERITYPE_SOUND) {
             (Math.random() * (2 * inst.volumeSwing + 1)).toInt() - inst.volumeSwing else 0
         voice.randomPanBias = if (inst.panSwing != 0)
             (Math.random() * (2 * inst.panSwing + 1)).toInt() - inst.panSwing else 0
-        // Default pan: applied unless the pattern row has already overridden channelPan.
+        // Default pan / pitch-pan separation: only re-applied when the row carried an instrument
-        // The pan envelope's 'p' flag ("use default pan") lives in the pan LOOP word at bit 7.
+        // byte. A note-only retrigger (instId == 0) inherits the channel's existing pan, mirroring
-        if ((inst.panEnvLoop ushr 7) and 1 != 0) {
+        // the volume policy below.
-            voice.channelPan = inst.defaultPan
+        if (instId != 0) {
-            voice.rowPan = (voice.channelPan ushr 2).coerceIn(0, 63)
+            // Default pan: applied unless the pattern row has already overridden channelPan.
-        }
+            // The pan envelope's 'p' flag ("use default pan") lives in the pan LOOP word at bit 7.
-        // Pitch-pan separation: when PPS != 0, played notes far from PPC drift in pan.
+            if ((inst.panEnvLoop ushr 7) and 1 != 0) {
-        // PPS is signed (-32..+32), full-scale at one octave (4096 4096-TET units) above PPC.
+                voice.channelPan = inst.defaultPan
-        if (inst.pitchPanSeparation != 0) {
+                voice.rowPan = (voice.channelPan ushr 2).coerceIn(0, 63)
-            val noteDelta = (noteVal - inst.pitchPanCentre).toDouble() / 4096.0
+            }
-            val panShift = (noteDelta * inst.pitchPanSeparation * 4.0).toInt()  // ~×4 = 32→128 swing
+            // Pitch-pan separation: when PPS != 0, played notes far from PPC drift in pan.
-            voice.channelPan = (voice.channelPan + panShift).coerceIn(0, 255)
+            // PPS is signed (-32..+32), full-scale at one octave (4096 4096-TET units) above PPC.
-            voice.rowPan = (voice.channelPan ushr 2).coerceIn(0, 63)
+            if (inst.pitchPanSeparation != 0) {
+                val noteDelta = (noteVal - inst.pitchPanCentre).toDouble() / 4096.0
+                val panShift = (noteDelta * inst.pitchPanSeparation * 4.0).toInt()  // ~×4 = 32→128 swing
+                voice.channelPan = (voice.channelPan + panShift).coerceIn(0, 255)
+                voice.rowPan = (voice.channelPan ushr 2).coerceIn(0, 63)
+            }
         }
         // Filter cutoff/resonance defaults — adjusted per-tick by the pf envelope when in filter mode.
         // 255 = filter off (IT high-bit-clear); 0..254 = active range matching IT 0..127 at double resolution.
@@ -1715,10 +1720,16 @@ class AudioAdapter(val vm: VM) : PeriBase(VM.PERITYPE_SOUND) {
         voice.amigaPeriod = -1.0   // fresh trigger: period state must reseed from the new noteVal
         voice.linearFreq  = -1.0   // ditto for linear-freq mode (toneMode == 2)
         voice.playbackRate = computePlaybackRate(inst, noteVal)
-        // Fresh trigger resets channel volume to full ($3F). Per-instrument scaling lives in
+        // Fresh trigger resets channel volume to full ($3F) ONLY when the row carried an
-        // instGlobalVolume (byte 171), which the mixer applies as a multiplier. Converters
+        // instrument byte; a note-only retrigger (instId == 0) inherits the channel's existing
-        // therefore no longer need to emit SEL_SET=Sv on note-trigger rows.
+        // volume so the user can sustain a held volume across re-triggered notes. Per-instrument
-        voice.channelVolume = if (volOverride >= 0) volOverride.coerceIn(0, 0x3F) else 0x3F
+        // scaling lives in instGlobalVolume (byte 171), which the mixer applies as a multiplier.
+        // Converters therefore no longer need to emit SEL_SET=Sv on note-trigger rows.
+        voice.channelVolume = when {
+            volOverride >= 0 -> volOverride.coerceIn(0, 0x3F)
+            instId != 0     -> 0x3F
+            else            -> voice.channelVolume
+        }
         voice.rowVolume = voice.channelVolume
         voice.noteWasCut = false
         voice.noteFading = false