feat(subtitles): optionally anchor text subtitles to the screen bottom

Adds an "Anchor to Screen" toggle under Subtitle Styling (Android +
ExoPlayer only, default off). When enabled, the text SubtitleView is
sized to the full container instead of the letterboxed video rect, so
SRT/VTT/mov_text cues render in the black bars below widescreen video
and font size and the position setting become relative to the physical
screen height. Bitmap (PGS/VOB) and ASS/libass rendering are unchanged;
mpv already places plaintext subtitles in the margins by default.

close #1730

android/app/src/main/kotlin/com/edde746/plezy/exoplayer/ExoPlayerCore.kt

@@ -215,6 +215,7 @@ class ExoPlayerCore(private val activity: Activity) :
   @Volatile private var assVideoLatencyFrames = 0
   private var subtitlePositionPercent: Int = 100
   private var subtitleFontSize: Float = 55f
+  private var subtitleAnchorToScreen: Boolean = false
   private var lastSubtitleCues: List<Cue> = emptyList()
 
   // Tracks whether a text track was selected on the previous onTracksChanged so we
@@ -1757,7 +1758,8 @@ class ExoPlayerCore(private val activity: Activity) :
       videoHeight,
       pixelRatio,
       resizeMode,
-      videoZoomScale
+      videoZoomScale,
+      subtitleAnchorToScreen
     )
     val bitmapDimensions = SubtitleViewLayout.bitmapDimensions(
       containerWidth,
@@ -3911,7 +3913,8 @@ class ExoPlayerCore(private val activity: Activity) :
     bgOpacity: Int,
     subtitlePosition: Int = 100,
     bold: Boolean = false,
-    italic: Boolean = false
+    italic: Boolean = false,
+    anchorToScreen: Boolean = false
   ) {
     activity.runOnUiThread {
       // 1. Non-ASS subtitles: CaptionStyleCompat on SubtitleView
@@ -3959,6 +3962,18 @@ class ExoPlayerCore(private val activity: Activity) :
       subtitlePositionPercent = clampedPosition
       subtitleFontSize = fontSize
 
+      // Anchor-to-screen (#1730): resize the text SubtitleView to the full
+      // container so default-placed cues land in the letterbox bars.
+      val anchorChanged = subtitleAnchorToScreen != anchorToScreen
+      subtitleAnchorToScreen = anchorToScreen
+      if (anchorChanged) {
+        lastVideoSize?.let { vs ->
+          if (vs.width > 0 && vs.height > 0) {
+            updateSubtitleViewSize(vs.width, vs.height, vs.pixelWidthHeightRatio)
+          }
+        }
+      }
+
       // Cue-level positioning handles default VTT/SRT placement, whose line
       // numbers bypass SubtitleView bottom padding. Authored VTT line positions
       // are preserved in applySubtitlePosition().
@@ -3980,7 +3995,7 @@ class ExoPlayerCore(private val activity: Activity) :
         Log.w(TAG, "Failed to set ASS font scale: ${e.message}")
       }
 
-      Log.d(TAG, "setSubtitleStyle: fontSize=$fontSize, textColor=$textColor, borderSize=$borderSize, bgOpacity=$bgOpacity, position=$subtitlePosition, bold=$bold, italic=$italic, assScale=$scale")
+      Log.d(TAG, "setSubtitleStyle: fontSize=$fontSize, textColor=$textColor, borderSize=$borderSize, bgOpacity=$bgOpacity, position=$subtitlePosition, bold=$bold, italic=$italic, anchorToScreen=$anchorToScreen, assScale=$scale")
     }
   }
 

android/app/src/main/kotlin/com/edde746/plezy/exoplayer/ExoPlayerPlugin.kt

@@ -1069,6 +1069,7 @@ class ExoPlayerPlugin :
     val subtitlePosition = call.argument<Number>("subtitlePosition")?.toInt() ?: 100
     val bold = call.argument<Boolean>("bold") ?: false
     val italic = call.argument<Boolean>("italic") ?: false
+    val anchorToScreen = call.argument<Boolean>("anchorToScreen") ?: false
 
     if (usingMpvFallback) {
       // MPV fallback handles styling via setProperty, no-op here
@@ -1076,7 +1077,7 @@ class ExoPlayerPlugin :
       return
     }
 
-    playerCore?.setSubtitleStyle(fontSize, textColor, borderSize, borderColor, bgColor, bgOpacity, subtitlePosition, bold, italic)
+    playerCore?.setSubtitleStyle(fontSize, textColor, borderSize, borderColor, bgColor, bgOpacity, subtitlePosition, bold, italic, anchorToScreen)
     result.success(null)
   }
 

android/app/src/main/kotlin/com/edde746/plezy/exoplayer/SubtitleViewLayout.kt

@@ -13,12 +13,18 @@ internal object SubtitleViewLayout {
     videoHeight: Int,
     pixelRatio: Float,
     resizeMode: Int,
-    zoomScale: Float
+    zoomScale: Float,
+    anchorToScreen: Boolean = false
   ): SubtitleViewDimensions? {
     val videoAspect = videoAspect(videoWidth, videoHeight, pixelRatio) ?: return null
     if (containerWidth <= 0 || containerHeight <= 0) return null
 
-    if (resizeMode != AspectRatioFrameLayout.RESIZE_MODE_FIT) {
+    // Anchor-to-screen (#1730): size the text view to the full container so
+    // media3's fractional text size and bottom-anchored cue placement compute
+    // against the physical screen, letting subtitles render in the letterbox
+    // bars instead of inside the video rect. Same geometry the non-FIT modes
+    // below already use.
+    if (anchorToScreen || resizeMode != AspectRatioFrameLayout.RESIZE_MODE_FIT) {
       return SubtitleViewDimensions(containerWidth, containerHeight)
     }
 

android/app/src/test/kotlin/com/edde746/plezy/exoplayer/SubtitleViewLayoutTest.kt

@@ -45,9 +45,49 @@ class SubtitleViewLayoutTest {
     assertAspectCloseTo16By9(bitmap!!)
   }
 
+  @Test
+  fun anchorToScreenSizesTextToContainerAndKeepsBitmapOnVideoRect() {
+    val text = textDimensions(resizeMode = AspectRatioFrameLayout.RESIZE_MODE_FIT, anchorToScreen = true)
+    val bitmap = bitmapDimensions(resizeMode = AspectRatioFrameLayout.RESIZE_MODE_FIT)
+
+    assertEquals(SubtitleViewDimensions(2424, 1080), text)
+    assertEquals(SubtitleViewDimensions(1920, 1080), bitmap)
+    assertAspectCloseTo16By9(bitmap!!)
+  }
+
+  @Test
+  fun anchorToScreenReachesBelowLetterboxedWideVideo() {
+    // 2.37:1 video on a 16:9 screen — the #1730 use case. Without the anchor
+    // the text view stops at the bottom letterbox bar; with it the view spans
+    // the physical screen height.
+    val unanchored = SubtitleViewLayout.textDimensions(
+      containerWidth = 1920,
+      containerHeight = 1080,
+      videoWidth = 2560,
+      videoHeight = 1080,
+      pixelRatio = 1f,
+      resizeMode = AspectRatioFrameLayout.RESIZE_MODE_FIT,
+      zoomScale = 1f
+    )
+    val anchored = SubtitleViewLayout.textDimensions(
+      containerWidth = 1920,
+      containerHeight = 1080,
+      videoWidth = 2560,
+      videoHeight = 1080,
+      pixelRatio = 1f,
+      resizeMode = AspectRatioFrameLayout.RESIZE_MODE_FIT,
+      zoomScale = 1f,
+      anchorToScreen = true
+    )
+
+    assertEquals(SubtitleViewDimensions(1920, 810), unanchored)
+    assertEquals(SubtitleViewDimensions(1920, 1080), anchored)
+  }
+
   private fun textDimensions(
     resizeMode: Int,
-    zoomScale: Float = 1f
+    zoomScale: Float = 1f,
+    anchorToScreen: Boolean = false
   ): SubtitleViewDimensions? = SubtitleViewLayout.textDimensions(
     containerWidth = 2424,
     containerHeight = 1080,
@@ -55,7 +95,8 @@ class SubtitleViewLayoutTest {
     videoHeight = 1080,
     pixelRatio = 1f,
     resizeMode = resizeMode,
-    zoomScale = zoomScale
+    zoomScale = zoomScale,
+    anchorToScreen = anchorToScreen
   )
 
   private fun bitmapDimensions(

lib/i18n/az.i18n.json

@@ -744,6 +744,8 @@
     "overrideStrip": "Formatlaşdırmanı sil",
     "positionTop": "Yuxarı",
     "positionBottom": "Aşağı",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Qalın",
     "italic": "Kursiv",
     "renderResolution": "Emal imkanı (Resolution)",

lib/i18n/bg.i18n.json

@@ -744,6 +744,8 @@
     "overrideStrip": "Премахване на стиловете",
     "positionTop": "Горе",
     "positionBottom": "Долу",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Получер",
     "italic": "Курсив",
     "renderResolution": "Резолюция на изобразяване",

lib/i18n/da.i18n.json

@@ -744,6 +744,8 @@
     "overrideStrip": "Fjern formatering",
     "positionTop": "Øverst",
     "positionBottom": "Nederst",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Fed",
     "italic": "Kursiv",
     "renderResolution": "Gengivelsesopløsning",

lib/i18n/de.i18n.json

@@ -744,6 +744,8 @@
     "overrideStrip": "Formatierung entfernen",
     "positionTop": "Oben",
     "positionBottom": "Unten",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Fett",
     "italic": "Kursiv",
     "renderResolution": "Render-Auflösung",

lib/i18n/en.i18n.json

@@ -744,6 +744,8 @@
     "overrideStrip": "Remove styling",
     "positionTop": "Top",
     "positionBottom": "Bottom",
+    "anchorToScreen": "Anchor to Screen",
+    "anchorToScreenDescription": "Show text subtitles in the black bars below widescreen video",
     "bold": "Bold",
     "italic": "Italic",
     "renderResolution": "Render Resolution",

lib/i18n/es.i18n.json

@@ -744,6 +744,8 @@
     "overrideStrip": "Quitar estilos",
     "positionTop": "Arriba",
     "positionBottom": "Abajo",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Negrita",
     "italic": "Cursiva",
     "renderResolution": "Resolución de renderizado",

lib/i18n/fr.i18n.json

@@ -744,6 +744,8 @@
     "overrideStrip": "Supprimer le style",
     "positionTop": "Haut",
     "positionBottom": "Bas",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Gras",
     "italic": "Italique",
     "renderResolution": "Résolution de rendu",

lib/i18n/hu.i18n.json

@@ -744,6 +744,8 @@
     "overrideStrip": "Stílus eltávolítása",
     "positionTop": "Fent",
     "positionBottom": "Lent",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Félkövér",
     "italic": "Dőlt",
     "renderResolution": "Renderelési felbontás",

lib/i18n/it.i18n.json

@@ -744,6 +744,8 @@
     "overrideStrip": "Rimuovi stile",
     "positionTop": "In alto",
     "positionBottom": "In basso",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Grassetto",
     "italic": "Corsivo",
     "renderResolution": "Risoluzione di rendering",

lib/i18n/ja.i18n.json

@@ -740,6 +740,8 @@
     "overrideStrip": "スタイルを削除",
     "positionTop": "上",
     "positionBottom": "下",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "太字",
     "italic": "斜体",
     "renderResolution": "レンダリング解像度",

lib/i18n/kk.i18n.json

@@ -744,6 +744,8 @@
     "overrideStrip": "Форматтауды жою",
     "positionTop": "Жоғары",
     "positionBottom": "Төмен",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Қалың",
     "italic": "Көлбеу",
     "renderResolution": "Рендеринг ажыратымдылығы",

lib/i18n/ko.i18n.json

@@ -740,6 +740,8 @@
     "overrideStrip": "스타일 제거",
     "positionTop": "위",
     "positionBottom": "아래",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "굵게",
     "italic": "기울임꼴",
     "renderResolution": "렌더링 해상도",

lib/i18n/nb.i18n.json

@@ -744,6 +744,8 @@
     "overrideStrip": "Fjern formatering",
     "positionTop": "Øverst",
     "positionBottom": "Nederst",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Fet",
     "italic": "Kursiv",
     "renderResolution": "Gjengivelsesoppløsning",

lib/i18n/nl.i18n.json

@@ -744,6 +744,8 @@
     "overrideStrip": "Opmaak verwijderen",
     "positionTop": "Bovenaan",
     "positionBottom": "Onderaan",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Vet",
     "italic": "Cursief",
     "renderResolution": "Renderresolutie",

lib/i18n/pl.i18n.json

@@ -752,6 +752,8 @@
     "overrideStrip": "Usuń style",
     "positionTop": "Góra",
     "positionBottom": "Dół",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Pogrubienie",
     "italic": "Kursywa",
     "renderResolution": "Rozdzielczość renderowania",

lib/i18n/pt.i18n.json

@@ -744,6 +744,8 @@
     "overrideStrip": "Remover estilo",
     "positionTop": "Superior",
     "positionBottom": "Inferior",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Negrito",
     "italic": "Itálico",
     "renderResolution": "Resolução de renderização",

lib/i18n/ru.i18n.json

@@ -752,6 +752,8 @@
     "overrideStrip": "Удалить стили",
     "positionTop": "Сверху",
     "positionBottom": "Снизу",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Жирный",
     "italic": "Курсив",
     "renderResolution": "Разрешение отрисовки",

lib/i18n/strings.g.dart

@@ -4,7 +4,7 @@
 /// To regenerate, run: `dart run slang`
 ///
 /// Locales: 22
-/// Strings: 38352 (1743 per locale)
+/// Strings: 38354 (1743 per locale)
 
 // coverage:ignore-file
 // ignore_for_file: type=lint, unused_import

lib/i18n/strings_en.g.dart

@@ -2212,6 +2212,12 @@ class Translations$subtitlingStyling$en {
 	/// en: 'Bottom'
 	String get positionBottom => 'Bottom';
 
+	/// en: 'Anchor to Screen'
+	String get anchorToScreen => 'Anchor to Screen';
+
+	/// en: 'Show text subtitles in the black bars below widescreen video'
+	String get anchorToScreenDescription => 'Show text subtitles in the black bars below widescreen video';
+
 	/// en: 'Bold'
 	String get bold => 'Bold';
 
@@ -6762,6 +6768,8 @@ extension on Translations {
 			'subtitlingStyling.overrideStrip' => 'Remove styling',
 			'subtitlingStyling.positionTop' => 'Top',
 			'subtitlingStyling.positionBottom' => 'Bottom',
+			'subtitlingStyling.anchorToScreen' => 'Anchor to Screen',
+			'subtitlingStyling.anchorToScreenDescription' => 'Show text subtitles in the black bars below widescreen video',
 			'subtitlingStyling.bold' => 'Bold',
 			'subtitlingStyling.italic' => 'Italic',
 			'subtitlingStyling.renderResolution' => 'Render Resolution',
@@ -7091,10 +7099,10 @@ extension on Translations {
 			'explore.stats.favorited' => ({required Object n}) => '${n} favorites',
 			'explore.stats.dropRate' => ({required Object percent}) => '${percent} dropped it',
 			'explore.stats.comments' => ({required num n}) => (_root.$meta.cardinalResolver ?? PluralResolvers.cardinal('en'))(n, one: '${n} comment', other: '${n} comments', ), 
-			'explore.stats.votes' => ({required Object n}) => '${n} votes',
-			'explore.stats.watching' => ({required Object n}) => '${n} watching it',
 			_ => null,
 		} ?? switch (path) {
+			'explore.stats.votes' => ({required Object n}) => '${n} votes',
+			'explore.stats.watching' => ({required Object n}) => '${n} watching it',
 			'explore.stats.completed' => ({required Object n}) => '${n} completed',
 			'explore.stats.onHold' => ({required Object n}) => '${n} on hold',
 			'explore.stats.dropped' => ({required Object n}) => '${n} dropped',
@@ -7605,10 +7613,10 @@ extension on Translations {
 			'externalPlayer.useExternalPlayerDescription' => 'Open videos in another app',
 			'externalPlayer.selectPlayer' => 'Select Player',
 			'externalPlayer.customPlayers' => 'Custom Players',
-			'externalPlayer.systemDefault' => 'System Default',
-			'externalPlayer.addCustomPlayer' => 'Add Custom Player',
 			_ => null,
 		} ?? switch (path) {
+			'externalPlayer.systemDefault' => 'System Default',
+			'externalPlayer.addCustomPlayer' => 'Add Custom Player',
 			'externalPlayer.playerName' => 'Player Name',
 			'externalPlayer.playerNameHint' => 'My Player',
 			'externalPlayer.playerCommand' => 'Command',

lib/i18n/sv.i18n.json

@@ -744,6 +744,8 @@
     "overrideStrip": "Ta bort formatering",
     "positionTop": "Överst",
     "positionBottom": "Nederst",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Fet",
     "italic": "Kursiv",
     "renderResolution": "Renderingsupplösning",

lib/i18n/tr.i18n.json

@@ -744,6 +744,8 @@
     "overrideStrip": "Biçimlendirmeyi kaldır",
     "positionTop": "Üst",
     "positionBottom": "Alt",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Kalın",
     "italic": "İtalik",
     "renderResolution": "İşleme Çözünürlüğü",

lib/i18n/uz.i18n.json

@@ -744,6 +744,8 @@
     "overrideStrip": "Formatlashni olib tashlash",
     "positionTop": "Yuqori",
     "positionBottom": "Pastki",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "Qalin",
     "italic": "Qiya",
     "renderResolution": "Renderlash oʻlchamlari",

lib/i18n/zh-Hant.i18n.json

@@ -740,6 +740,8 @@
     "overrideStrip": "移除樣式",
     "positionTop": "頂部",
     "positionBottom": "底部",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "粗體",
     "italic": "斜體",
     "renderResolution": "渲染解析度",

lib/i18n/zh.i18n.json

@@ -740,6 +740,8 @@
     "overrideStrip": "移除样式",
     "positionTop": "顶部",
     "positionBottom": "底部",
+    "anchorToScreen": "",
+    "anchorToScreenDescription": "",
     "bold": "粗体",
     "italic": "斜体",
     "renderResolution": "渲染分辨率",

lib/mpv/player/platform/player_android.dart

@@ -542,6 +542,7 @@ class PlayerAndroid extends PlayerBase {
     int subtitlePosition = 100,
     bool bold = false,
     bool italic = false,
+    bool anchorToScreen = false,
   }) async {
     if (disposed || !initialized) return;
     await invoke('setSubtitleStyle', {
@@ -554,6 +555,7 @@ class PlayerAndroid extends PlayerBase {
       'subtitlePosition': subtitlePosition,
       'bold': bold,
       'italic': italic,
+      'anchorToScreen': anchorToScreen,
     });
   }
 

lib/mpv/player/player.dart

@@ -314,6 +314,7 @@ abstract class Player {
     int subtitlePosition = 100,
     bool bold = false,
     bool italic = false,
+    bool anchorToScreen = false,
   });
 
   /// Apply the box-fit mode to the native video layer

lib/mpv/player/player_base.dart

@@ -1097,6 +1097,7 @@ abstract class PlayerBase with PlayerStreamControllersMixin implements Player {
     int subtitlePosition = 100,
     bool bold = false,
     bool italic = false,
+    bool anchorToScreen = false,
   }) async {}
 
   @override

lib/screens/settings/subtitle_styling_screen.dart

@@ -42,6 +42,9 @@ class SubtitleStylingScreen extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
+    // Anchor-to-screen is an ExoPlayer text-subtitle knob; mpv already places
+    // plaintext subtitles in the letterbox margins by default.
+    final exoActive = Platform.isAndroid && SettingsService.instance.read(SettingsService.useExoPlayer);
     return SettingsPage(
       title: Text(t.screens.subtitleStyling),
       children: [
@@ -108,6 +111,13 @@ class SubtitleStylingScreen extends StatelessWidget {
               min: 0,
               max: 100,
             ),
+            if (exoActive)
+              SettingSwitchTile(
+                pref: SettingsService.subtitleAnchorToScreen,
+                icon: Symbols.fit_screen_rounded,
+                title: t.subtitlingStyling.anchorToScreen,
+                subtitle: t.subtitlingStyling.anchorToScreenDescription,
+              ),
             SettingSwitchTile(
               pref: SettingsService.subtitleBold,
               icon: Symbols.format_bold_rounded,

lib/screens/video_player/parts/playback_open.dart

@@ -432,6 +432,7 @@ extension _VideoPlayerOpenMethods on VideoPlayerScreenState {
       subtitlePosition: settingsService.read(SettingsService.subtitlePosition),
       bold: settingsService.read(SettingsService.subtitleBold),
       italic: settingsService.read(SettingsService.subtitleItalic),
+      anchorToScreen: settingsService.read(SettingsService.subtitleAnchorToScreen),
     );
   }
 

lib/services/settings_service.dart

@@ -377,6 +377,12 @@ class SettingsService extends BaseSharedPreferencesService {
   );
   static const subtitleBold = BoolPref('subtitle_bold');
   static const subtitleItalic = BoolPref('subtitle_italic');
+
+  /// Render text subtitles (SRT/VTT/mov_text) anchored to the physical screen
+  /// instead of the video rect, so they land in the letterbox bars of
+  /// widescreen video (#1730). ExoPlayer backend only; mpv already places
+  /// plaintext subtitles in the margins by default (sub-use-margins=yes).
+  static const subtitleAnchorToScreen = BoolPref('subtitle_anchor_to_screen');
   static const cleanedOldImageCache = BoolPref('cleaned_old_image_cache');
   static const rememberTrackSelections = BoolPref('remember_track_selections', defaultValue: true);
 
@@ -935,6 +941,7 @@ class SettingsService extends BaseSharedPreferencesService {
     maxVolume,
     downmixCenterBoost,
     subtitlePosition,
+    subtitleAnchorToScreen,
     defaultPlaybackSpeed,
     defaultBoxFitMode,
     themeMode,

test/services/music/music_playback_service_test.dart

@@ -368,6 +368,7 @@ class FakePlayer implements Player {
     int subtitlePosition = 100,
     bool bold = false,
     bool italic = false,
+    bool anchorToScreen = false,
   }) async {}
 
   @override