adjust smoothing in now playing spectrum

src/components/SpectrumCurve.tsx

@@ -34,6 +34,8 @@ interface SpectrumCurveProps {
   frameMs?: number;
   /** Native pull cadence. Defaults to frameMs; 0 advances analysis every display frame. */
   analysisFrameMs?: number;
+  /** Previous native spectrum-frame retention in [0, 0.99]. */
+  smoothing?: number;
   dbMin?: number;
   dbMax?: number;
   tiltDbPerOctave?: number;
@@ -54,6 +56,7 @@ type SkiaViewApiShape = {
 
 const DEFAULT_POINTS = 120;
 const MINI_FRAME_MS = 32;
+const DEFAULT_SMOOTHING = 0.92;
 const DISPLAY_DB_MIN = -90;
 const DISPLAY_DB_MAX = -10;
 const SPECTRUM_SAMPLE_RATE = 48000;
@@ -376,6 +379,7 @@ export function SpectrumCurve({
   pointCount,
   frameMs = MINI_FRAME_MS,
   analysisFrameMs,
+  smoothing = DEFAULT_SMOOTHING,
   dbMin = DISPLAY_DB_MIN,
   dbMax = DISPLAY_DB_MAX,
   tiltDbPerOctave = TILT_DB_PER_OCT,
@@ -567,8 +571,8 @@ export function SpectrumCurve({
         lastAnalysis = t;
         const got =
           source === 'post'
-            ? AstraScope.getSpectrumFramePostEq(spectrumBins)
-            : AstraScope.getSpectrumFrame(spectrumBins);
+            ? AstraScope.getSpectrumFramePostEq(spectrumBins, smoothing)
+            : AstraScope.getSpectrumFrame(spectrumBins, smoothing);
         if (got > 0) {
           writeSpectrumPoints(spectrumBins, renderValues, pointOptions);
           hasNewFrame = true;
@@ -601,6 +605,7 @@ export function SpectrumCurve({
     reduceMotion,
     resolvedPointCount,
     source,
+    smoothing,
     tiltDbPerOctave,
     width,
   ]);

src/components/Visualizer.tsx

@@ -25,6 +25,7 @@ interface VisualizerProps {
   showChrome?: boolean;
   mode?: Mode;
   edgeFade?: boolean;
+  spectrumSmoothing?: number;
   /** Freeze the live scopes without unmounting (e.g. while occluded by an overlay). */
   paused?: boolean;
 }
@@ -41,6 +42,7 @@ export function Visualizer({
   showChrome = true,
   mode: controlledMode,
   edgeFade = false,
+  spectrumSmoothing,
   paused = false,
 }: VisualizerProps) {
   const styles = useStyles();
@@ -72,6 +74,7 @@ export function Visualizer({
           <SpectrumCurve
             active={spectrumActive}
             frameMs={STAGE_FRAME_MS}
+            smoothing={spectrumSmoothing}
             width={width}
             height={height}
             glow

src/components/player/NowPlayingOverlay.tsx

@@ -109,6 +109,7 @@ const SUB_ICON_SIZE = 20;
 const MENU_ANIMATION_IN_MS = 130;
 const MENU_ANIMATION_OUT_MS = 100;
 const MENU_ENTER_OFFSET_Y = -8;
+const NOW_PLAYING_SPECTRUM_SMOOTHING = 0.85;
 
 interface NowPlayingMenuItem {
   key: string;
@@ -983,6 +984,7 @@ export function NowPlayingOverlay() {
                           size={artBoxSize}
                           stripWidth={layout.scopeWidth}
                           artworkUri={backdropArtworkUri}
+                          spectrumSmoothing={NOW_PLAYING_SPECTRUM_SMOOTHING}
                           paused={!playerOpen || queueOpen || !effectiveScopeStageVisible}
                         />
                       </Animated.View>
@@ -1457,6 +1459,7 @@ function ScopeRail({ width, height, mode, paused, revealed, onSwap }: ScopeRailP
         showChrome={false}
         mode={mode}
         edgeFade
+        spectrumSmoothing={NOW_PLAYING_SPECTRUM_SMOOTHING}
         paused={paused}
       />
       <Animated.View pointerEvents="none" style={[styles.scopeSwap, labelStyle]}>

src/components/player/ScopeRack.tsx

@@ -35,6 +35,7 @@ interface ScopeRackProps {
   /** Strip span (the rail's width): wider than the card, overflowing it. */
   stripWidth: number;
   artworkUri: string | null;
+  spectrumSmoothing?: number;
   /** Freeze the scopes without unmounting (overlay closed / queue open). */
   paused?: boolean;
 }
@@ -45,7 +46,13 @@ interface ScopeRackProps {
  * backdrop dissolves past the former card frame, while the strips span the
  * full rail width and independently fade at their ends.
  */
-export function ScopeRack({ size, stripWidth, artworkUri, paused = false }: ScopeRackProps) {
+export function ScopeRack({
+  size,
+  stripWidth,
+  artworkUri,
+  spectrumSmoothing,
+  paused = false,
+}: ScopeRackProps) {
   const styles = useStyles();
   const artwork = useImage(artworkUri);
   const active = useScopeActive() && !paused;
@@ -114,6 +121,7 @@ export function ScopeRack({ size, stripWidth, artworkUri, paused = false }: Scop
         <SpectrumCurve
           active={active}
           frameMs={STAGE_FRAME_MS}
+          smoothing={spectrumSmoothing}
           width={width}
           height={stripHeight}
           glow