DV: Update tile selection to defer replace refinement until global selection

lerna.json

@@ -6,7 +6,6 @@
     "bootstrap": {}
   },
   "npmClient": "yarn",
-  "useWorkspaces": true,
   "exact": true,
   "packages": [
     "modules/*"

modules/tiles/src/tileset/grouped-tiles.array.ts

@@ -14,8 +14,82 @@ export class GroupedTilesArray {
     this.array.push(other);
   }
 
-  addTilesOrGroups(other: GroupedTilesArray) {
-    this.array.push(...other.array);
+  /**
+   * Adds the content of another GroupedTilesArray instance to this one.
+   * Optionally, a maximum size can be specified which will add items in
+   * order of _displayPriority up until the maximum size is reached.
+   * @param other The other instance to read from
+   * @param maxSize Optional maximum size of this GroupedTilesArray after
+   * the operation.
+   */
+  addTilesOrGroups(other: GroupedTilesArray, maxSize: number = 0) {
+    const totalItems = this.array.length + other.array.length;
+
+    if (maxSize <= 0 || totalItems <= maxSize) {
+      // unlimited, or enough space to append all elements
+      this.array = this.array.concat(other.array);
+    } else {
+      // add as many items as possible by display priority, up to the maximum size
+      const replacedTileIds = new Set<string>();
+      let itemsToAdd = maxSize - this.array.length;
+
+      // shallow copy of other array to not modify other group
+      const otherArray = other.array.slice();
+
+      // ensure array is sorted DESCENDING by priority
+      otherArray.sort((a, b) => b._displayPriority - a._displayPriority);
+
+      while (itemsToAdd > 0 && otherArray.length > 0) {
+        // popping off end means iterating the list ASCENDING in priority
+        const nextItem = otherArray.pop()!; // safe assertion as we just checked the length
+
+        const nextItemReplacedIds =
+          nextItem instanceof Tile3D
+            ? [nextItem._replacedTileId]
+            : nextItem.tiles.map((tile) => tile._replacedTileId);
+
+        const tilesInItem = nextItem instanceof Tile3D ? 1 : nextItem.tiles.length;
+        if (tilesInItem > itemsToAdd) {
+          // can't add the next item as it'd make the list too long
+          break;
+        }
+
+        // add the item
+        this.array.push(nextItem);
+        itemsToAdd -= tilesInItem;
+
+        // update replaced tile Ids (and increase the count if needed)
+        for (let i = 0; i < nextItemReplacedIds.length; i++) {
+          const replacedTileId = nextItemReplacedIds[i];
+
+          if (replacedTileId !== undefined && !replacedTileIds.has(replacedTileId)) {
+            // we're replacing a new item, so we need to add an extra item
+            itemsToAdd++;
+            replacedTileIds.add(replacedTileId);
+          }
+        }
+      }
+
+      // splice out any replaced tiles
+      this.array = this.array
+        .map((tileOrGroup) => {
+          if (tileOrGroup instanceof TileGroup3D) {
+            const filteredGroup = new TileGroup3D();
+
+            for (let i = 0; i < tileOrGroup.tiles.length; i++) {
+              const tile = tileOrGroup.tiles[i];
+              if (!replacedTileIds.has(tile.id)) {
+                filteredGroup.addTile(tile);
+              }
+            }
+
+            return filteredGroup.tiles.length > 0 ? filteredGroup : null;
+          }
+
+          return !replacedTileIds.has(tileOrGroup.id) ? tileOrGroup : null;
+        })
+        .filter((item): item is Tile3D | TileGroup3D => item !== null);
+    }
   }
 
   numTiles() {

modules/tiles/src/tileset/tileset-traverser.ts

@@ -136,12 +136,12 @@ export class TilesetTraverser {
 
         // replace tiles
       } else if (tile.refine === TILE_REFINEMENT.REPLACE) {
-        // Always load tiles in the base traversal
-        // Select tiles that can't refine further
+        // Always load and select replacement tiles (so we can handle refinement at a global scale later)
+        // note (ck): This differs from the normal loadersgl implementation as we want to keep track of replaced
+        // root nodes so we can decide which level of detail to render based on the global tile budget rather than
+        // a per tile budget.
         this.loadTile(tile, frameState);
-        if (stoppedRefining) {
-          this.selectTile(tile, frameState);
-        }
+        this.selectTile(tile, frameState);
       }
 
       // 3. update cache, most recent touched tiles have higher priority to be fetched from server
@@ -259,8 +259,8 @@ export class TilesetTraverser {
       // only be necessary to set the replacedTileId once, on load.
       if (tile.parent?.refine === TILE_REFINEMENT.REPLACE) {
         // The root tile of a tileset does not have an ID, so when the tileset root is a REPLACE
-        // tile , its children set the _replacedTileId to the URL for the whole tileset.
-        tile._replacedTileId = tile.parent._replacedTileId ?? tile.parent.id ?? tile.tileset.url;
+        // tile, its children set the _replacedTileId to the URL for the whole tileset.
+        tile._replacedTileId = tile.parent.id ?? tile.tileset.url;
       }
     }
   }

package.json

@@ -64,5 +64,9 @@
   "volta": {
     "node": "18.19.0",
     "yarn": "4.1.1"
-  }
+  },
+  "dependencies": {
+    "lerna": "^8.1.8"
+  },
+  "packageManager": "yarn@1.22.22+sha512.a6b2f7906b721bba3d67d4aff083df04dad64c399707841b7acf00f6b133b7ac24255f2652fa22ae3534329dc6180534e98d17432037ff6fd140556e2bb3137e"
 }