Fix unbounded tree node growth in XYZ globe image tiles

src/core/renderer/tiles/TilesRendererBase.js

@@ -885,6 +885,18 @@ export class TilesRendererBase {
 		// remove any tiles that are loading but no longer used
 		this.removeUnusedPendingTiles();
 
+		const plugins = this.plugins;
+		for ( let i = 0, l = plugins.length; i < l; i ++ ) {
+
+			const plugin = plugins[ i ];
+			if ( plugin.pruneUnusedSubtrees ) {
+
+				plugin.pruneUnusedSubtrees();
+
+			}
+
+		}
+
 		// TODO: This will only sort for one tileset. We may want to store this queue on the
 		// LRUCache so multiple tilesets can use it at once
 		// start the downloads of the tiles as needed
@@ -1347,6 +1359,18 @@ export class TilesRendererBase {
 
 	ensureChildrenArePreprocessed( tile, forceImmediate = this.stats.tilesProcessed < this.maxTilesProcessed ) {
 
+		const plugins = this.plugins;
+		for ( let i = 0, l = plugins.length; i < l; i ++ ) {
+
+			const plugin = plugins[ i ];
+			if ( plugin.ensureChildrenAreExpanded ) {
+
+				plugin.ensureChildrenAreExpanded( tile );
+
+			}
+
+		}
+
 		const children = tile.children;
 		if ( children.length === 0 || children[ children.length - 1 ].traversal ) {
 

src/core/renderer/tiles/optimizedTraverseFunctions.js

@@ -48,8 +48,6 @@ function canUnconditionallyRefine( tile ) {
 // Resets the frame information for the given tile
 function resetFrameState( tile, renderer ) {
 
-	renderer.ensureChildrenArePreprocessed( tile );
-
 	if ( tile.traversal.lastFrameVisited !== renderer.frameCount ) {
 
 		tile.traversal.lastFrameVisited = renderer.frameCount;
@@ -164,6 +162,8 @@ function canTraverse( tile, renderer ) {
 
 	}
 
+	renderer.ensureChildrenArePreprocessed( tile );
+
 	// Early out if the children haven't been processed, yet
 	if ( ! areChildrenProcessed( tile ) ) {
 

src/core/renderer/tiles/traverseFunctions.js

@@ -72,14 +72,19 @@ function resetFrameState( tile, renderer ) {
 // Recursively mark tiles used down to the next layer, skipping external tilesets
 function recursivelyMarkUsed( tile, renderer, cacheOnly = false ) {
 
-	renderer.ensureChildrenArePreprocessed( tile );
-
 	resetFrameState( tile, renderer );
 	markUsed( tile, renderer, cacheOnly );
 
 	// don't traverse if the children have not been processed, yet but tileset content
 	// should be considered to be "replaced" by the loaded children so await that here.
-	if ( canUnconditionallyRefine( tile ) && areChildrenProcessed( tile ) ) {
+	if ( canUnconditionallyRefine( tile ) ) {
+
+		renderer.ensureChildrenArePreprocessed( tile );
+		if ( ! areChildrenProcessed( tile ) ) {
+
+			return;
+
+		}
 
 		const children = tile.children;
 		for ( let i = 0, l = children.length; i < l; i ++ ) {
@@ -95,8 +100,6 @@ function recursivelyMarkUsed( tile, renderer, cacheOnly = false ) {
 // Recursively traverses to the next tiles with unloaded renderable content to load them
 function recursivelyLoadNextRenderableTiles( tile, renderer ) {
 
-	renderer.ensureChildrenArePreprocessed( tile );
-
 	// exit the recursion if the tile hasn't been used this frame
 	if ( isUsedThisFrame( tile, renderer.frameCount ) ) {
 
@@ -167,6 +170,8 @@ function canTraverse( tile, renderer ) {
 
 	}
 
+	renderer.ensureChildrenArePreprocessed( tile );
+
 	// Early out if the children haven't been processed, yet
 	if ( ! areChildrenProcessed( tile ) ) {
 
@@ -181,10 +186,6 @@ function canTraverse( tile, renderer ) {
 // Determine which tiles are used by the renderer given the current camera configuration
 function markUsedTiles( tile, renderer ) {
 
-	// determine frustum set is run first so we can ensure the preprocessing of all the necessary
-	// child tiles has happened here.
-	renderer.ensureChildrenArePreprocessed( tile );
-
 	resetFrameState( tile, renderer );
 
 	if ( ! tile.traversal.inFrustum ) {