Restore smooth realtime fall ballistics

scripts/test_gui_contracts.mjs

@@ -4,6 +4,7 @@ import assert from 'node:assert/strict';
 const html = fs.readFileSync(new URL('../www/index.html', import.meta.url), 'utf8');
 const main = fs.readFileSync(new URL('../www/main.js', import.meta.url), 'utf8');
 const audio = fs.readFileSync(new URL('../www/core/audio.js', import.meta.url), 'utf8');
+const realtime = fs.readFileSync(new URL('../www/views/realtime.js', import.meta.url), 'utf8');
 
 const styleSelect = html.match(/<select\b[^>]*\bid="styleSel"[^>]*>/)?.[0] || '';
 assert(styleSelect, 'style selector is missing');
@@ -29,5 +30,11 @@ assert(!/requestAnimationFrame/.test(audio),
   'audio transport must not create requestAnimationFrame loops that compete with the canvas loop');
 assert(!/while\s*\(pendingPhoenixFrame\)/.test(audio),
   'metrics transport must coalesce bursts instead of draining every queued state');
+assert(!/syncNativePeakHold/.test(realtime),
+  'native RTA peak anchors must not be copied directly into the visible hold line');
+assert((realtime.match(/applyPeakHold\(state, integrated, CONFIG, range\)/g) || []).length >= 3,
+  'every RTA engine must advance peak hold on the display clock');
+assert(/useIirEngine[^]*?applyRealtimeBarBallistics\(state, displayBase, CONFIG, range\)/.test(realtime),
+  'native IIR bars must advance their visible release on the display clock');
 
 console.log('GUI contract regression tests passed');

scripts/test_rta_profile.mjs

@@ -2,7 +2,12 @@ import assert from 'node:assert/strict';
 import fs from 'node:fs';
 import vm from 'node:vm';
 import { getRtwCenters } from '../www/core/rtw_centers.js';
-import { buildRtwTickPositions, selectLocalRtwPacket } from '../www/views/realtime.js';
+import {
+  applyPeakHold,
+  applyRealtimeBarBallistics,
+  buildRtwTickPositions,
+  selectLocalRtwPacket,
+} from '../www/views/realtime.js';
 
 const source = fs.readFileSync(new URL('../www/core/audio.js', import.meta.url), 'utf8');
 const configSource = fs.readFileSync(new URL('../www/core/config.js', import.meta.url), 'utf8');
@@ -118,4 +123,33 @@ for (const mode of ['1_3', '1_6', '1_12']) {
   }
 }
 
+const range = { bottom: -36, top: 9 };
+const peakNow = performance.now();
+const peakState = {
+  peakHold: new Float32Array([8]),
+  lastPeakTime: [peakNow - 3000],
+  holdSampleTs: peakNow - (1000 / 60),
+};
+const repeatedPeakAnchor = new Float32Array([-36]);
+const peakAfterOneFrame = applyPeakHold(peakState, repeatedPeakAnchor, {
+  RTA_PEAK_HOLD_MODE: 'fall',
+  RTA_PEAK_HOLD_SEC: 2.5,
+  RTA_PEAK_DECAY_DB_PER_S: 20,
+}, range)[0];
+assert.ok(peakAfterOneFrame < 7.8 && peakAfterOneFrame > 7.5,
+  `a repeated native peak anchor must still fall once per display frame, got ${peakAfterOneFrame}`);
+
+const barNow = performance.now();
+const barState = {
+  rtBarLevels: new Float32Array([8]),
+  rtBarPeakTimes: [barNow - 1000],
+  lastRtBarTs: barNow - (1000 / 60),
+};
+const barAfterOneFrame = applyRealtimeBarBallistics(barState, new Float32Array([-36]), {
+  REALTIME_BAR_HOLD_MS: 0,
+  REALTIME_BAR_DECAY_DB_PER_S: 20,
+}, range)[0];
+assert.ok(barAfterOneFrame < 7.8 && barAfterOneFrame > 7.5,
+  `a repeated native bar anchor must still fall once per display frame, got ${barAfterOneFrame}`);
+
 console.log('RTA profile regression tests passed');

src/audio.rs

@@ -40,6 +40,7 @@ use crate::{
     model::{InputSource, MeterFrame, PhoenixRtaConfig},
 };
 
+#[cfg(not(target_os = "linux"))]
 const PLACEHOLDER_UPDATES_PER_SECOND: u32 = 120;
 
 #[derive(Clone, Copy, Debug, Default)]

src/goniometer.rs

@@ -1,10 +1,12 @@
 //! Timing and sample-selection helpers for the realtime goniometer stream.
 
+#[cfg(test)]
 #[derive(Clone, Debug, Default)]
 pub struct GoniometerClock {
     phase: u64,
 }
 
+#[cfg(test)]
 impl GoniometerClock {
     /// Returns true at the first capture boundary after the next display tick.
     /// The fractional phase is retained, so the average rate is independent

www/views/realtime.js

@@ -200,10 +200,13 @@ export async function render(env, state) {
       } else {
         const integrated = baseLevels;
         const displayBase = applyDisplayHold(state, integrated, CONFIG, range);
-        // Native IIR values already contain the selected power-domain
-        // integration. A second browser attack/hold stage would falsify it.
-        const display = displayBase;
-        syncNativePeakHold(state, displayRtaPacket, CONFIG, range, state.mapping.length, 'iir');
+        // Detector integration remains authoritative in the native DSP. The
+        // display-only hold/release stages advance on every VSync so repeated
+        // transport anchors cannot freeze a falling bar or peak hairline.
+        const display = (CONFIG.REALTIME_RENDER_STYLE || 'bars') === 'bars'
+          ? applyRealtimeBarBallistics(state, displayBase, CONFIG, range)
+          : displayBase;
+        applyPeakHold(state, integrated, CONFIG, range);
         state.displayLevels = display;
         state.currentRange = range;
         if (typeof window !== 'undefined') window.__RTA_STATE__ = state;
@@ -237,7 +240,7 @@ export async function render(env, state) {
         const display = (CONFIG.REALTIME_RENDER_STYLE || 'bars') === 'bars'
           ? applyRealtimeBarBallistics(state, displayBase, CONFIG, range)
           : displayBase;
-        syncNativePeakHold(state, displayRtaPacket, CONFIG, range, state.mapping.length, 'fft');
+        applyPeakHold(state, integrated, CONFIG, range);
         state.displayLevels = display;
         state.currentRange = range;
         if (typeof window !== 'undefined') window.__RTA_STATE__ = state;
@@ -439,7 +442,7 @@ function applyIntegration(state, levels, CONFIG, range) {
   return buffer;
 }
 
-function applyPeakHold(state, levels, CONFIG, range) {
+export function applyPeakHold(state, levels, CONFIG, range) {
   const mode = CONFIG.RTA_PEAK_HOLD_MODE || 'fall';
   const len = levels.length;
   const mapped = PEAK_HOLD_MAP.get(mode);
@@ -482,28 +485,6 @@ function applyPeakHold(state, levels, CONFIG, range) {
   return buffer;
 }
 
-function syncNativePeakHold(state, packet, CONFIG, range, expectedLen, engine) {
-  const src = isVectorLike(packet?.bands_peak) && packet.bands_peak.length === expectedLen
-    ? packet.bands_peak
-    : null;
-  if (!src) return applyPeakHold(state, state.displayLevels, CONFIG, range);
-  const gain = engine === 'iir'
-    ? (Number(CONFIG.RTA_DISPLAY_GAIN_IIR_DB ?? 0) || 0)
-    : (Number(CONFIG.RTA_DISPLAY_GAIN_FFT_DB ?? 0) || 0);
-  if (!state.peakHold || state.peakHold.length !== expectedLen) {
-    state.peakHold = new Float32Array(expectedLen);
-  }
-  for (let i = 0; i < expectedLen; i++) {
-    const value = Number(src[i]);
-    state.peakHold[i] = clamp(
-      (Number.isFinite(value) ? value : range.bottom) + gain,
-      range.bottom,
-      range.top,
-    );
-  }
-  return state.peakHold;
-}
-
 function applyDisplayHold(state, levels, CONFIG, range) {
   const holdSec = Math.max(0, Number(CONFIG.RTA_DISPLAY_HOLD_SEC) || 0);
   const len = levels.length;
@@ -538,7 +519,7 @@ function applyDisplayHold(state, levels, CONFIG, range) {
   return buffer;
 }
 
-function applyRealtimeBarBallistics(state, levels, CONFIG, range) {
+export function applyRealtimeBarBallistics(state, levels, CONFIG, range) {
   const holdMs = Math.max(0, Number(CONFIG.REALTIME_BAR_HOLD_MS) || 0);
   const decayRate = Math.max(0, Number(CONFIG.REALTIME_BAR_DECAY_DB_PER_S) || 0);
   const len = levels.length;