fix(filmstrip) Excludes partially visible tiles for dominant speaker slot.

react/features/filmstrip/actions.any.ts

@@ -60,16 +60,19 @@ export function setRemoteParticipants(participants: Array<string>) {
  *
  * @param {number} startIndex - The start index from the remote participants array.
  * @param {number} endIndex - The end index from the remote participants array.
+ * @param {number} fullyVisibleCount - The number of fully visible participants (excluding partially visible).
  * @returns {{
  *      type: SET_VISIBLE_REMOTE_PARTICIPANTS,
  *      startIndex: number,
- *      endIndex: number
+ *      endIndex: number,
+ *      fullyVisibleCount: number
  * }}
  */
-export function setVisibleRemoteParticipants(startIndex: number, endIndex: number) {
+export function setVisibleRemoteParticipants(startIndex: number, endIndex: number, fullyVisibleCount?: number) {
     return {
         type: SET_VISIBLE_REMOTE_PARTICIPANTS,
         startIndex,
-        endIndex
+        endIndex,
+        fullyVisibleCount
     };
 }

react/features/filmstrip/components/native/Filmstrip.tsx

@@ -10,6 +10,7 @@ import { ASPECT_RATIO_NARROW } from '../../../base/responsive-ui/constants';
 import { getHideSelfView } from '../../../base/settings/functions.any';
 import { isToolboxVisible } from '../../../toolbox/functions.native';
 import { setVisibleRemoteParticipants } from '../../actions.native';
+import { calculateFullyVisibleParticipantsCount } from '../../functions.any';
 import {
     getFilmstripDimensions,
     isFilmstripVisible,
@@ -190,7 +191,7 @@ class Filmstrip extends PureComponent<IProps> {
      * @returns {void}
      */
     _onViewableItemsChanged({ viewableItems = [] }: { viewableItems: ViewToken[]; }) {
-        const { _disableSelfView } = this.props;
+        const { _aspectRatio, _clientWidth, _clientHeight, _disableSelfView } = this.props;
 
         if (!this._separateLocalThumbnail && !_disableSelfView && viewableItems[0]?.index === 0) {
             // Skip the local thumbnail.
@@ -205,13 +206,31 @@ class Filmstrip extends PureComponent<IProps> {
         let startIndex = Number(viewableItems[0].index);
         let endIndex = Number(viewableItems[viewableItems.length - 1].index);
 
+        // Calculate fully visible count (excluding partially visible tiles)
+        const isNarrowAspectRatio = _aspectRatio === ASPECT_RATIO_NARROW;
+        const { height: thumbnailHeight, width: thumbnailWidth, margin } = styles.thumbnail;
+        const { height, width } = this._getDimensions();
+
+        // Calculate item size and container size based on layout orientation
+        const itemSize = isNarrowAspectRatio
+            ? thumbnailWidth + (2 * margin) // Horizontal layout
+            : thumbnailHeight + (2 * margin); // Vertical layout
+        const containerSize = isNarrowAspectRatio ? width : height;
+
+        const fullyVisibleCount = calculateFullyVisibleParticipantsCount(
+            startIndex,
+            endIndex,
+            containerSize,
+            itemSize
+        );
+
         if (!this._separateLocalThumbnail && !_disableSelfView) {
             // We are off by one in the remote participants array.
             startIndex -= 1;
             endIndex -= 1;
         }
 
-        this.props.dispatch(setVisibleRemoteParticipants(startIndex, endIndex));
+        this.props.dispatch(setVisibleRemoteParticipants(startIndex, endIndex, fullyVisibleCount));
     }
 
     /**

react/features/filmstrip/components/web/Filmstrip.tsx

@@ -44,6 +44,7 @@ import {
     TOP_FILMSTRIP_HEIGHT,
     TOUCH_DRAG_HANDLE_PADDING
 } from '../../constants';
+import { calculateFullyVisibleParticipantsCount } from '../../functions.any';
 import {
     getVerticalViewMaxWidth,
     isFilmstripDisabled,
@@ -944,10 +945,33 @@ class Filmstrip extends PureComponent <IProps, IState> {
      */
     _onListItemsRendered({ visibleStartIndex, visibleStopIndex }: {
         visibleStartIndex: number; visibleStopIndex: number; }) {
-        const { dispatch } = this.props;
+        const {
+            dispatch,
+            _currentLayout,
+            _filmstripWidth,
+            _filmstripHeight,
+            _thumbnailWidth,
+            _thumbnailHeight,
+            _isVerticalFilmstrip
+        } = this.props;
+
+        // Calculate fully visible count (excluding partially visible tiles)
+        const isHorizontal = _currentLayout === LAYOUTS.HORIZONTAL_FILMSTRIP_VIEW;
+        const itemSize = isHorizontal
+            ? _thumbnailWidth + TILE_HORIZONTAL_MARGIN
+            : _thumbnailHeight + TILE_VERTICAL_MARGIN;
+        const containerSize = isHorizontal ? _filmstripWidth : _filmstripHeight;
+
+        const fullyVisibleCount = calculateFullyVisibleParticipantsCount(
+            visibleStartIndex,
+            visibleStopIndex,
+            containerSize,
+            itemSize
+        );
+
         const { startIndex, stopIndex } = this._calculateIndices(visibleStartIndex, visibleStopIndex);
 
-        dispatch(setVisibleRemoteParticipants(startIndex, stopIndex));
+        dispatch(setVisibleRemoteParticipants(startIndex, stopIndex, fullyVisibleCount));
     }
 
     /**

react/features/filmstrip/functions.any.ts

@@ -45,7 +45,7 @@ export function updateRemoteParticipants(store: IStore, force?: boolean, partici
         ? [ ...sortedRemoteVirtualScreenshareParticipants.keys() ] : [];
     const sharedVideos = fakeParticipants ? Array.from(fakeParticipants.keys()) : [];
     const speakers = new Array<string>();
-    const { visibleRemoteParticipants } = state['features/filmstrip'];
+    const { fullyVisibleRemoteParticipantsCount } = state['features/filmstrip'];
 
     const participantsWithScreenShare = screenShareParticipants.reduce<string[]>((acc, screenshare) => {
         const ownerId = getVirtualScreenshareParticipantOwnerId(screenshare);
@@ -69,9 +69,13 @@ export function updateRemoteParticipants(store: IStore, force?: boolean, partici
         speakers.push(dominant.id);
     }
 
-    // Find the number of slots available for speakers.
+    // Find the number of slots available for speakers. Use fullyVisibleRemoteParticipantsCount to exclude partially
+    // visible tiles, ensuring dominant speaker is placed on a fully visible tile.
     const slotsForSpeakers
-        = visibleRemoteParticipants.size - (screenShareParticipants.length * 2) - sharedVideos.length - dominantSpeakerSlot;
+        = fullyVisibleRemoteParticipantsCount
+        - (screenShareParticipants.length * 2)
+        - sharedVideos.length
+        - dominantSpeakerSlot;
 
     // Construct the list of speakers to be shown.
     if (slotsForSpeakers > 0) {
@@ -127,3 +131,31 @@ export function isTileViewModeDisabled(state: IReduxState) {
 
     return tileView.disabled;
 }
+
+/**
+ * Calculates the count of fully visible participants, excluding any partially visible tiles.
+ * This respects the actual rendered items from the list component while accounting for
+ * container padding/gaps.
+ *
+ * @param {number} visibleStartIndex - The start index of visible items.
+ * @param {number} visibleEndIndex - The end index of visible items.
+ * @param {number} containerSize - The width or height of the filmstrip container.
+ * @param {number} itemSize - The width or height of each item including margin.
+ * @returns {number} - The count of fully visible participants (at least 1).
+ */
+export function calculateFullyVisibleParticipantsCount(
+        visibleStartIndex: number,
+        visibleEndIndex: number,
+        containerSize: number,
+        itemSize: number
+): number {
+    // Current visible count from the list component (includes any partially visible tile)
+    const currentVisibleCount = visibleEndIndex - visibleStartIndex + 1;
+
+    // Theoretical max that can fit fully in the container
+    const maxFullyVisible = Math.floor(containerSize / itemSize);
+
+    // Fully visible count is the minimum of actual visible and max that can fit fully
+    // Ensure at least 1 if there are any visible items
+    return Math.max(1, Math.min(currentVisibleCount, maxFullyVisible));
+}

react/features/filmstrip/reducer.ts

@@ -158,6 +158,15 @@ const DEFAULT_STATE = {
      */
     visibleRemoteParticipants: new Set<string>(),
 
+    /**
+     * The number of fully visible remote participants (excluding partially visible ones).
+     * Used for calculating speaker slots to avoid placing dominant speaker on partially visible tiles.
+     *
+     * @public
+     * @type {number}
+     */
+    fullyVisibleRemoteParticipantsCount: 0,
+
     /**
      * The width of the resizable filmstrip.
      *
@@ -201,6 +210,7 @@ export interface IFilmstripState {
         pinned?: boolean;
     }>;
     enabled: boolean;
+    fullyVisibleRemoteParticipantsCount: number;
     horizontalViewDimensions: {
         hasScroll?: boolean;
         local?: IDimensions;
@@ -301,15 +311,16 @@ ReducerRegistry.register<IFilmstripState>(
                 }
             };
         case SET_VISIBLE_REMOTE_PARTICIPANTS: {
-            const { endIndex, startIndex } = action;
+            const { endIndex, startIndex, fullyVisibleCount } = action;
             const { remoteParticipants } = state;
             const visibleRemoteParticipants = new Set(remoteParticipants.slice(startIndex, endIndex + 1));
 
             return {
                 ...state,
                 visibleParticipantsStartIndex: startIndex,
                 visibleParticipantsEndIndex: endIndex,
-                visibleRemoteParticipants
+                visibleRemoteParticipants,
+                fullyVisibleRemoteParticipantsCount: fullyVisibleCount ?? visibleRemoteParticipants.size
             };
         }
         case PARTICIPANT_LEFT: {