Add initial ol.structs.Buffer

src/ol/structs/buffer.js

@@ -0,0 +1,137 @@
+goog.provide('ol.structs.Buffer');
+
+goog.require('ol.structs.IntegerSet');
+
+
+
+/**
+ * @constructor
+ * @param {Array.<number>=} opt_arr Array.
+ * @param {number=} opt_used Used.
+ * @param {boolean=} opt_dirty Dirty.
+ */
+ol.structs.Buffer = function(opt_arr, opt_used, opt_dirty) {
+
+  /**
+   * @private
+   * @type {Array.<number>}
+   */
+  this.arr_ = goog.isDef(opt_arr) ? opt_arr : [];
+
+  /**
+   * @private
+   * @type {ol.structs.IntegerSet}
+   */
+  this.dirtySet_ = new ol.structs.IntegerSet();
+
+  /**
+   * @private
+   * @type {ol.structs.IntegerSet}
+   */
+  this.freeSet_ = new ol.structs.IntegerSet();
+
+  var used = goog.isDef(opt_used) ? opt_used : this.arr_.length;
+  if (used < this.arr_.length) {
+    this.freeSet_.addRange(used, this.arr_.length);
+  }
+  if (opt_dirty && used !== 0) {
+    this.dirtySet_.addRange(0, used);
+  }
+
+};
+
+
+/**
+ * @param {Array.<number>} values Values.
+ * @return {number} Index.
+ */
+ol.structs.Buffer.prototype.add = function(values) {
+  var size = values.length;
+  goog.asserts.assert(size > 0);
+  var index = this.freeSet_.findRange(size);
+  goog.asserts.assert(index != -1);  // FIXME
+  this.freeSet_.removeRange(index, index + size);
+  var i;
+  for (i = 0; i < size; ++i) {
+    this.arr_[index + i] = values[i];
+  }
+  this.dirtySet_.addRange(index, index + size);
+  return index;
+};
+
+
+/**
+ * @param {function(this: T, number, number)} f Callback.
+ * @param {T=} opt_obj The object to be used as the value of 'this' within f.
+ * @template T
+ */
+ol.structs.Buffer.prototype.forEachRange = function(f, opt_obj) {
+  if (this.arr_.length !== 0) {
+    this.freeSet_.forEachRangeInverted(0, this.arr_.length, f, opt_obj);
+  }
+};
+
+
+/**
+ * @return {Array.<number>} Array.
+ */
+ol.structs.Buffer.prototype.getArray = function() {
+  return this.arr_;
+};
+
+
+/**
+ * @return {number} Count.
+ */
+ol.structs.Buffer.prototype.getCount = function() {
+  return this.arr_.length - this.freeSet_.getSize();
+};
+
+
+/**
+ * @return {ol.structs.IntegerSet} Dirty set.
+ */
+ol.structs.Buffer.prototype.getDirtySet = function() {
+  return this.dirtySet_;
+};
+
+
+/**
+ * @return {ol.structs.IntegerSet} Free set.
+ */
+ol.structs.Buffer.prototype.getFreeSet = function() {
+  return this.freeSet_;
+};
+
+
+/**
+ * @param {number} index Index.
+ * @param {number} size Size.
+ */
+ol.structs.Buffer.prototype.remove = function(index, size) {
+  this.freeSet_.addRange(index, index + size);
+  this.dirtySet_.removeRange(index, index + size);
+};
+
+
+/**
+ * @param {number} index Index.
+ * @param {Array.<number>} values Values.
+ */
+ol.structs.Buffer.prototype.set = function(index, values) {
+  var arr = this.arr_;
+  var n = values.length;
+  goog.asserts.assert(0 <= index && index + n <= arr.length);
+  for (i = 0; i < n; ++i) {
+    arr[index + i] = values[i];
+  }
+  this.dirtySet_.addRange(index, index + n);
+};
+
+
+/**
+ * Marks the buffer as being clean.
+ */
+ol.structs.Buffer.prototype.setClean = function() {
+  this.dirtySet_.clear();
+};