Add existing to tracked

node_modules/@cesium/engine/Source/Scene/BufferPoint.js

@@ -0,0 +1,149 @@
+// @ts-check
+
+import BufferPrimitive from "./BufferPrimitive.js";
+import Cartesian3 from "../Core/Cartesian3.js";
+import assert from "../Core/assert.js";
+import BufferPrimitiveCollection from "./BufferPrimitiveCollection.js";
+
+/** @import BufferPointCollection from "./BufferPointCollection.js"; */
+
+const { ERR_CAPACITY } = BufferPrimitiveCollection.Error;
+
+const scratchCartesian = new Cartesian3();
+
+/**
+ * View bound to the underlying buffer data of a {@link BufferPointCollection}.
+ *
+ * <p>BufferPoint instances are {@link https://en.wikipedia.org/wiki/Flyweight_pattern|flyweights}:
+ * a single BufferPoint instance can be temporarily bound to any conceptual
+ * "point" in a BufferPointCollection, allowing very large collections to be
+ * iterated and updated with a minimal memory footprint.</p>
+ *
+ * Represented as one (1) position.
+ *
+ * @see BufferPointCollection
+ * @see BufferPointMaterial
+ * @see BufferPrimitive
+ * @experimental This feature is not final and is subject to change without Cesium's standard deprecation policy.
+ * @extends BufferPrimitive
+ */
+class BufferPoint extends BufferPrimitive {
+  /**
+   * @type {BufferPointCollection}
+   * @ignore
+   */
+  _collection = null;
+
+  /** @ignore */
+  static Layout = {
+    ...BufferPrimitive.Layout,
+
+    /**
+     * Offset in position array to current point vertex, number of VEC3 elements.
+     * @type {number}
+     * @ignore
+     */
+    POSITION_OFFSET_U32: BufferPrimitive.Layout.__BYTE_LENGTH,
+
+    /**
+     * @type {number}
+     * @ignore
+     */
+    __BYTE_LENGTH: BufferPrimitive.Layout.__BYTE_LENGTH + 4,
+  };
+
+  /////////////////////////////////////////////////////////////////////////////
+  // LIFECYCLE
+
+  /**
+   * Copies data from source point to result.
+   *
+   * @param {BufferPoint} point
+   * @param {BufferPoint} result
+   * @return {BufferPoint}
+   * @override
+   */
+  static clone(point, result) {
+    super.clone(point, result);
+    result.setPosition(point.getPosition(scratchCartesian));
+    return result;
+  }
+
+  /////////////////////////////////////////////////////////////////////////////
+  // GEOMETRY
+
+  /**
+   * Offset in collection position array to position of this point, number
+   * of VEC3 elements.
+   *
+   * @type {number}
+   * @readonly
+   * @ignore
+   */
+  get vertexOffset() {
+    return this._getUint32(BufferPoint.Layout.POSITION_OFFSET_U32);
+  }
+
+  /**
+   * Count of positions (vertices) in this primitive. Always 1.
+   *
+   * @type {number}
+   * @readonly
+   */
+  get vertexCount() {
+    return 1;
+  }
+
+  /**
+   * Gets the position of this point.
+   *
+   * @param {Cartesian3} [result]
+   * @returns {Cartesian3}
+   */
+  getPosition(result) {
+    const positionF64 = this._collection._positionView;
+    // @ts-expect-error TODO(tsd-jsdoc): See https://github.com/CesiumGS/cesium/pull/13302.
+    return Cartesian3.fromArray(positionF64, this.vertexOffset * 3, result);
+  }
+
+  /**
+   * Sets the position of this point.
+   *
+   * @param {Cartesian3} position
+   */
+  setPosition(position) {
+    const collection = this._collection;
+    const vertexOffset = this.vertexOffset;
+
+    //>>includeStart('debug', pragmas.debug);
+    assert(vertexOffset < collection.vertexCountMax, ERR_CAPACITY);
+    //>>includeEnd('debug');
+
+    collection._positionView[vertexOffset * 3] = position.x;
+    collection._positionView[vertexOffset * 3 + 1] = position.y;
+    collection._positionView[vertexOffset * 3 + 2] = position.z;
+
+    this._dirty = true;
+    collection._makeDirtyBoundingVolume();
+  }
+
+  /////////////////////////////////////////////////////////////////////////////
+  // DEBUG
+
+  /**
+   * Returns a JSON-serializable object representing the point. This encoding
+   * is not memory-efficient, and should generally be used for debugging and
+   * testing.
+   *
+   * @returns {Object} JSON-serializable object.
+   * @override
+   */
+  toJSON() {
+    return {
+      ...super.toJSON(),
+      position: Cartesian3.pack(this.getPosition(), []),
+    };
+  }
+}
+
+export default BufferPoint;