Restructured library.

lib/pixi/deepzoom/tile.js

@@ -0,0 +1,77 @@
+
+export const deepZoomTileCache = new Map()
+
+
+/** The current Tile implementation simply uses PIXI.Sprites.
+ *
+ * BTW: PIXI.extras.TilingSprite is not appropriate. It should be used for
+ * repeating patterns.
+ **/
+export class Tile extends PIXI.Sprite {
+    constructor(texture, url) {
+        super(texture)
+        this.url = url
+        this.register(url)
+    }
+
+    static fromImage(imageId, crossorigin, scaleMode) {
+        return new Tile(PIXI.Texture.fromImage(imageId, crossorigin, scaleMode), imageId)
+    }
+
+    /**
+     * Registers the tile in the global reference counter for textures
+     *
+     * @param {*} url
+     * @param {boolean} [debug=false]
+     * @memberof Tile
+     */
+    register(url, debug = false) {
+        if (deepZoomTileCache.has(url)) {
+            let tiles = deepZoomTileCache.get(url)
+            tiles.add(this)
+            if (debug) console.log("Tile.register", url, tiles.size)
+        }
+        else {
+            deepZoomTileCache.set(url, new Set([this]))
+            if (debug) console.log("Tile.register", url, 1)
+        }
+    }
+
+    /**
+     * Unregisters the rile in the global reference counter for textures
+     *
+     * @returns {number} The number of how often a texture is used.
+     * @memberof Tile
+     */
+    unregister() {
+        let tiles = deepZoomTileCache.get(this.url)
+        tiles.delete(this)
+        if (tiles.size == 0) {
+            deepZoomTileCache.delete(this.url)
+        }
+        return tiles.size
+    }
+
+    /**
+     * Destroys this sprite and optionally its texture and children
+     *
+     * @param {*} options  Part of the PIXI API, but ignored in the implementation
+     * @memberof Tile
+     */
+    destroy(options, debug = false) {
+        if (this.parent != null) {
+
+        }
+        let count = this.unregister()
+        if (count <= 0) {
+            let opts = { children: true, texture: true, baseTexture: true }
+            super.destroy(opts)
+            if (debug) console.log("Tile.destroy", deepZoomTileCache.size, opts)
+        }
+        else {
+            let opts = { children: true, texture: false, baseTexture: false }
+            if (debug) console.log("Tile.destroy", deepZoomTileCache.size, opts)
+            super.destroy(opts)
+        }
+    }
+}