perf(render): bypass redundant viewer lookups

Author: Arbousier1

src/main/java/top/ellan/mahjong/table/render/SparrowRayInteractionProxyCoordinator.java

@@ -78,23 +78,23 @@ synchronized void replace(
                 if (viewerId == null || interactions == null || interactions.isEmpty()) {
                     continue;
                 }
-                Player viewer = this.session.onlinePlayer(viewerId);
-                if (viewer == null || !viewer.isOnline()) {
-                    continue;
-                }
                 ActiveProxies current = previous.get(viewerId);
-                if (this.canReuse(viewerId, viewer, current, interactions)) {
+                if (current != null
+                    && current.viewer().isOnline()
+                    && this.canReuse(viewerId, current, interactions)) {
                     next.put(viewerId, current);
                     continue;
                 }
-                List<DisplayInteractionRayRegistry.RayInteraction> stableInteractions = List.copyOf(interactions);
-                List<InteractionGeometry> geometry = interactionGeometry(stableInteractions);
-                List<ClientProxy> proxies = List.copyOf(this.backend.create(viewer, stableInteractions));
+                Player viewer = this.session.onlinePlayer(viewerId);
+                if (viewer == null || !viewer.isOnline()) {
+                    continue;
+                }
+                List<InteractionGeometry> geometry = interactionGeometry(interactions);
+                List<ClientProxy> proxies = List.copyOf(this.backend.create(viewer, interactions));
                 if (!proxies.isEmpty()) {
                     ActiveProxies created = new ActiveProxies(
                         viewer,
                         proxies,
-                        stableInteractions,
                         geometry,
                         proxies.get(0).entityId()
                     );
@@ -156,12 +156,10 @@ private boolean canReuseRegion(
             if (viewerId == null || interactions == null || interactions.isEmpty()) {
                 continue;
             }
-            Player viewer = this.session.onlinePlayer(viewerId);
-            if (viewer == null || !viewer.isOnline()) {
-                continue;
-            }
             ActiveProxies active = previous.get(viewerId);
-            if (!this.canReuse(viewerId, viewer, active, interactions)) {
+            if (active == null
+                || !active.viewer().isOnline()
+                || !this.canReuse(viewerId, active, interactions)) {
                 return false;
             }
             reusableViewers++;
@@ -171,14 +169,10 @@ private boolean canReuseRegion(
 
     private boolean canReuse(
         UUID viewerId,
-        Player viewer,
         ActiveProxies active,
         List<DisplayInteractionRayRegistry.RayInteraction> interactions
     ) {
-        if (active == null || active.viewer() != viewer || active.proxies().isEmpty()) {
-            return false;
-        }
-        if (active.interactions() != interactions && !sameGeometry(active.geometry(), interactions)) {
+        if (active == null || active.proxies().isEmpty() || !sameGeometry(active.geometry(), interactions)) {
             return false;
         }
         return this.hasOwnership(viewerId, active);
@@ -391,7 +385,6 @@ interface ClientProxy {
     private record ActiveProxies(
         Player viewer,
         List<ClientProxy> proxies,
-        List<DisplayInteractionRayRegistry.RayInteraction> interactions,
         List<InteractionGeometry> geometry,
         int firstEntityId
     ) {

src/test/java/top/ellan/mahjong/table/render/SparrowRayInteractionProxyCoordinatorTest.java

@@ -126,7 +126,7 @@ void clearedViewerOwnershipMakesAnUnchangedRegionStaleForReconnect() {
     }
 
     @Test
-    void sameImmutableInteractionSnapshotReusesWithoutRepeatedIdentityReads() {
+    void unchangedRegionReusesWithoutRepeatedSessionOrIdentityReads() {
         TableSessionContext session = mock(TableSessionContext.class);
         SparrowRayInteractionProxyCoordinator.Backend backend = mock(
             SparrowRayInteractionProxyCoordinator.Backend.class
@@ -162,11 +162,12 @@ void sameImmutableInteractionSnapshotReusesWithoutRepeatedIdentityReads() {
         verify(backend, times(1)).spawn(viewer, List.of(proxy));
         verify(proxy, times(1)).entityId();
         verify(session, times(1)).id();
+        verify(session, times(1)).onlinePlayer(VIEWER_ID);
         assertEquals(1, coordinator.entityCount());
     }
 
     @Test
-    void mutableInteractionListGeometryChangeCannotHitIdentityFastPath() {
+    void mutableInteractionListGeometryChangeForcesRebuild() {
         TableSessionContext session = mock(TableSessionContext.class);
         SparrowRayInteractionProxyCoordinator.Backend backend = mock(
             SparrowRayInteractionProxyCoordinator.Backend.class
@@ -256,6 +257,55 @@ void multipleProxyOwnershipRemainsCompleteWithCachedFirstEntityId() {
         verify(secondProxy, times(3)).entityId();
     }
 
+    @Test
+    void offlineCachedViewerUsesFreshSessionPlayer() {
+        TableSessionContext session = mock(TableSessionContext.class);
+        SparrowRayInteractionProxyCoordinator.Backend backend = mock(
+            SparrowRayInteractionProxyCoordinator.Backend.class
+        );
+        SparrowRayInteractionProxyCoordinator.ClientProxy firstProxy = mock(
+            SparrowRayInteractionProxyCoordinator.ClientProxy.class
+        );
+        SparrowRayInteractionProxyCoordinator.ClientProxy reconnectedProxy = mock(
+            SparrowRayInteractionProxyCoordinator.ClientProxy.class
+        );
+        Player firstViewer = mock(Player.class);
+        Player reconnectedViewer = mock(Player.class);
+        when(session.id()).thenReturn("table-a");
+        when(session.onlinePlayer(VIEWER_ID)).thenReturn(firstViewer).thenReturn(reconnectedViewer);
+        when(firstViewer.isOnline()).thenReturn(true);
+        when(reconnectedViewer.isOnline()).thenReturn(true);
+        when(backend.available()).thenReturn(true);
+        when(backend.create(eq(firstViewer), any())).thenReturn(List.of(firstProxy));
+        when(backend.create(eq(reconnectedViewer), any())).thenReturn(List.of(reconnectedProxy));
+        when(firstProxy.entityId()).thenReturn(1211);
+        when(reconnectedProxy.entityId()).thenReturn(1212);
+        doAnswer(invocation -> {
+            invocation.<Runnable>getArgument(1).run();
+            return null;
+        }).when(session).runForViewer(any(Player.class), any(Runnable.class));
+        SparrowRayInteractionProxyCoordinator coordinator = new SparrowRayInteractionProxyCoordinator(
+            session,
+            backend
+        );
+        Map<UUID, List<DisplayInteractionRayRegistry.RayInteraction>> interactions = Map.of(
+            VIEWER_ID,
+            List.of(interaction())
+        );
+
+        coordinator.replace("actions", interactions);
+        when(firstViewer.isOnline()).thenReturn(false);
+        coordinator.replace("actions", interactions);
+
+        verify(backend).spawn(firstViewer, List.of(firstProxy));
+        verify(backend).spawn(reconnectedViewer, List.of(reconnectedProxy));
+        verify(backend, never()).destroy(firstViewer, List.of(firstProxy));
+        verify(session, times(2)).onlinePlayer(VIEWER_ID);
+        assertNull(ClientInteractionProxyRegistry.tableIdFor(1211, VIEWER_ID));
+        assertEquals("table-a", ClientInteractionProxyRegistry.tableIdFor(1212, VIEWER_ID));
+        assertEquals(1, coordinator.entityCount());
+    }
+
     @Test
     void cachedEntityCountTracksTheSameViewerAcrossMultipleRegions() {
         TableSessionContext session = mock(TableSessionContext.class);