Add correlation marker modes

scripts/test_goniometer.mjs

@@ -8,6 +8,10 @@ assert.ok(functionSource, 'persistence resolver must remain testable');
 const context = vm.createContext({ Number, String, Math });
 vm.runInContext(functionSource.replace('export function', 'function'), context);
 
+const markerFunctionSource = source.match(/export function resolveCorrelationNegativeMarker[\s\S]*?\n\}/)?.[0];
+assert.ok(markerFunctionSource, 'correlation marker resolver must remain testable');
+vm.runInContext(`const CORR_HOLD_MS = 4000;\n${markerFunctionSource.replace('export function', 'function')}`, context);
+
 assert.equal(context.resolveGoniometerPersistenceMs({ GONIO_PERSISTENCE_MODE: 'fast' }), 50);
 assert.equal(context.resolveGoniometerPersistenceMs({ GONIO_PERSISTENCE_MODE: 'medium' }), 150);
 assert.equal(context.resolveGoniometerPersistenceMs({ GONIO_PERSISTENCE_MODE: 'slow' }), 300);
@@ -28,4 +32,29 @@ assert.match(source, /pool\.pop\(\)/, 'trail buffers must be reused');
 assert.doesNotMatch(source, /utils\.correlation\(/,
   'browser must not recalculate or smooth backend correlation');
 
+const markerState = {
+  corrNegativeMarkerMode: 'memory',
+  corrHoldPeak: 0,
+  corrHoldUntil: 0,
+  corrResetToken: 0,
+};
+assert.equal(context.resolveCorrelationNegativeMarker(
+  markerState, { CORR_NEGATIVE_MARKER_MODE: 'memory' }, -0.2, -0.8, 1000
+), -0.8, 'memory mode must display the continuous DSP negative peak');
+assert.equal(context.resolveCorrelationNegativeMarker(
+  markerState, { CORR_NEGATIVE_MARKER_MODE: 'off' }, -0.9, -0.9, 1100
+), 0, 'off mode must hide the negative marker');
+assert.equal(context.resolveCorrelationNegativeMarker(
+  markerState, { CORR_NEGATIVE_MARKER_MODE: 'hold' }, -0.4, -0.9, 2000
+), -0.4, 'hold mode must start from the current correlation');
+assert.equal(context.resolveCorrelationNegativeMarker(
+  markerState, { CORR_NEGATIVE_MARKER_MODE: 'hold' }, -0.2, -0.9, 5000
+), -0.4, 'hold mode must retain its negative peak for four seconds');
+assert.equal(context.resolveCorrelationNegativeMarker(
+  markerState, { CORR_NEGATIVE_MARKER_MODE: 'hold' }, -0.2, -0.9, 6000
+), -0.2, 'hold mode must release to the current value after four seconds');
+assert.equal(context.resolveCorrelationNegativeMarker(
+  markerState, { CORR_NEGATIVE_MARKER_MODE: 'hold', CORR_RESET_TOKEN: 1 }, 0.2, -0.9, 6100
+), 0, 'reset must clear the four-second hold as well');
+
 console.log('goniometer regression tests passed');

www/core/config.js

@@ -190,6 +190,7 @@ const CONFIG = {
   CORR_ZERO_ON_SILENCE: false,
   CORR_SILENCE_THRESHOLD_RMS_DBFS: -75,
   CORR_RESPONSE_S: 1.0,
+  CORR_NEGATIVE_MARKER_MODE: 'memory',
   CORR_RESET_TOKEN: 0,
   XY_POINTS: 1024,
   XY_STYLE: 'lines',
@@ -958,6 +959,10 @@ function loadConfig(opts = {}) {
       CONFIG.GONIO_MANUAL_GAIN_DB = Math.max(-35, Math.min(35, Math.round(fallback / 5) * 5));
     }
     CONFIG.CORR_RESPONSE_S = Number(CONFIG.CORR_RESPONSE_S) >= 1.75 ? 2.5 : 1.0;
+    const corrNegativeMarkerMode = String(CONFIG.CORR_NEGATIVE_MARKER_MODE || 'memory').toLowerCase();
+    CONFIG.CORR_NEGATIVE_MARKER_MODE = ['memory', 'hold', 'off'].includes(corrNegativeMarkerMode)
+      ? corrNegativeMarkerMode
+      : 'memory';
     CONFIG.CORR_RESET_TOKEN = Math.max(0, Math.floor(Number(CONFIG.CORR_RESET_TOKEN) || 0));
     const persistenceMode = String(CONFIG.GONIO_PERSISTENCE_MODE || 'fast').toLowerCase();
     CONFIG.GONIO_PERSISTENCE_MODE = ['fast', 'medium', 'slow', 'custom'].includes(persistenceMode)

www/index.html

@@ -534,9 +534,17 @@
             </select>
             <small>Kontinuierliche DSP-Integration; unabhängig von Bildrate und ALSA-Periode.</small>
           </div>
+          <div class="opt"><label>Korrelations-Negativmarker</label>
+            <select id="opt_corrNegativeMarkerMode">
+              <option value="memory">Memory</option>
+              <option value="hold">Hold (4 Sekunden)</option>
+              <option value="off">Off</option>
+            </select>
+            <small>Memory bleibt bis zum Zurücksetzen stehen; Hold speichert die negativste Anzeige vier Sekunden.</small>
+          </div>
           <div class="opt">
             <button id="opt_corrResetPeak" type="button">Negativspitze zurücksetzen</button>
-            <small>Setzt den Negative-Peak-Memory auf 0 zurück; der rote Marker verschwindet.</small>
+            <small>Setzt den gespeicherten Negativmarker zurück. Im Modus Off bleibt der Marker ausgeblendet.</small>
           </div>
           <div class="opt"><label>Goniometer Display Gain (dB)</label>
             <input id="opt_goniGain" type="range" min="-35" max="35" step="5"><span id="val_goniGain"></span>

www/ui/options.js

@@ -271,6 +271,7 @@ function syncUI() {
     ['opt_rmsColWarn', CONFIG.RMS_COLOR_WARN],
 
     ['opt_corrResponse', String(Number(CONFIG.CORR_RESPONSE_S) >= 1.75 ? 2.5 : 1)],
+    ['opt_corrNegativeMarkerMode', CONFIG.CORR_NEGATIVE_MARKER_MODE || 'memory'],
     ['opt_xyPoints', String(CONFIG.XY_POINTS)],
     ['opt_xyStyle', CONFIG.XY_STYLE],
     ['opt_xySilenceGate', CONFIG.XY_SILENCE_GATE_ENABLED, null, null, 'checkbox'],
@@ -929,6 +930,13 @@ function wireHandlers(env) {
     try { env?.notifyRtaConfig?.(); } catch (_) {}
     return String(CONFIG.CORR_RESPONSE_S);
   });
+  h('opt_corrNegativeMarkerMode', v => {
+    const mode = String(v || '').toLowerCase();
+    CONFIG.CORR_NEGATIVE_MARKER_MODE = ['memory', 'hold', 'off'].includes(mode)
+      ? mode
+      : 'memory';
+    return CONFIG.CORR_NEGATIVE_MARKER_MODE;
+  });
   const corrResetPeak = E('opt_corrResetPeak');
   if (corrResetPeak) corrResetPeak.onclick = () => {
     CONFIG.CORR_RESET_TOKEN = Math.max(0, Math.floor(Number(CONFIG.CORR_RESET_TOKEN) || 0)) + 1;

www/views/goniometer_rtw.js

@@ -24,6 +24,7 @@ const BASE_ZOOM = 1.0;
 const BASE_GONIO_SCALE = (BASE_TARGET / ALIGN_PEAK) * Math.pow(10, -BASE_HEADROOM_DB / 20) * BASE_ZOOM;
 const AGC_TARGET_DB = linearToDb(ALIGN_PEAK);
 const CORR_SILENCE_THRESHOLD_DEFAULT = -75;
+const CORR_HOLD_MS = 4000;
 const MAX_TRAIL_FRAMES = 48;
 
 function computePanelSlotWidth(canvasWidth, slotCount = METER_SLOTS, slotGap = 12) {
@@ -48,6 +49,10 @@ export function init() {
     staticLayerCanvas: null,
     staticLayerCtx: null,
     staticLayerKey: '',
+    corrNegativeMarkerMode: 'memory',
+    corrHoldPeak: 0,
+    corrHoldUntil: 0,
+    corrResetToken: 0,
   };
 }
 
@@ -99,9 +104,16 @@ export async function render(env, state) {
   // Correlation is measured continuously in the audio DSP. Do not add a
   // second, frame-rate-dependent browser integration here.
   const corrVisual = Number.isFinite(audio?.correlation) ? clamp1(audio.correlation) : 0;
-  const corrNegativePeak = Number.isFinite(audio?.correlationNegativePeak)
+  const corrMemoryPeak = Number.isFinite(audio?.correlationNegativePeak)
     ? clamp1(audio.correlationNegativePeak)
     : 0;
+  const corrNegativeMarker = resolveCorrelationNegativeMarker(
+    state,
+    CONFIG,
+    corrVisual,
+    corrMemoryPeak,
+    frameNow,
+  );
   drawCorrelationBar(
     g,
     layout.plot.x + layout.plot.w / 2,
@@ -109,7 +121,7 @@ export async function render(env, state) {
     Math.round(Math.min(layout.scope.w * 0.75, layout.plot.w - 50)),
     18,
     corrVisual,
-    corrNegativePeak,
+    corrNegativeMarker,
   );
 
   if (slots.length) {
@@ -123,6 +135,34 @@ export async function render(env, state) {
   }
 }
 
+export function resolveCorrelationNegativeMarker(state, CONFIG = {}, current = 0, memoryPeak = 0, nowMs = 0) {
+  const requestedMode = String(CONFIG.CORR_NEGATIVE_MARKER_MODE || 'memory').toLowerCase();
+  const mode = ['memory', 'hold', 'off'].includes(requestedMode) ? requestedMode : 'memory';
+  const resetToken = Math.max(0, Math.floor(Number(CONFIG.CORR_RESET_TOKEN) || 0));
+
+  if (state.corrResetToken !== resetToken || state.corrNegativeMarkerMode !== mode) {
+    state.corrResetToken = resetToken;
+    state.corrNegativeMarkerMode = mode;
+    state.corrHoldPeak = 0;
+    state.corrHoldUntil = 0;
+  }
+
+  if (mode === 'off') return 0;
+  if (mode === 'memory') return Math.max(-1, Math.min(1, Number(memoryPeak) || 0));
+
+  const now = Number.isFinite(nowMs) ? nowMs : 0;
+  const currentNegative = Math.min(0, Math.max(-1, Math.min(1, Number(current) || 0)));
+  const holdActive = Number.isFinite(state.corrHoldUntil) && now < state.corrHoldUntil;
+  if (!holdActive) {
+    state.corrHoldPeak = currentNegative;
+    state.corrHoldUntil = currentNegative < -0.001 ? now + CORR_HOLD_MS : 0;
+  } else if (currentNegative < state.corrHoldPeak) {
+    state.corrHoldPeak = currentNegative;
+    state.corrHoldUntil = now + CORR_HOLD_MS;
+  }
+  return Number.isFinite(state.corrHoldPeak) ? state.corrHoldPeak : 0;
+}
+
 function drawStaticLayer(g, state, rect, layout, CONFIG, slotCount) {
   const layer = ensureStaticLayer(state, rect, layout, CONFIG, slotCount);
   if (!layer) {