Add ol.geom2.LineStringCollection

src/ol/geom2/linestringcollection.exports

@@ -0,0 +1,2 @@
+@exportSymbol ol.geom2.LineStringCollection
+@exportSymbol ol.geom2.LineStringCollection.pack

src/ol/geom2/linestringcollection.js

@@ -0,0 +1,183 @@
+goog.provide('ol.geom2.LineString');
+goog.provide('ol.geom2.LineStringCollection');
+
+goog.require('goog.asserts');
+goog.require('goog.object');
+goog.require('ol.geom2');
+goog.require('ol.structs.Buffer');
+
+
+/**
+ * @typedef {Array.<Array.<number>>}
+ */
+ol.geom2.LineString;
+
+
+
+/**
+ * @constructor
+ * @param {ol.structs.Buffer} buf Buffer.
+ * @param {Object.<number, Array.<number>>=} opt_ranges Ranges.
+ * @param {number=} opt_dim Dimension.
+ */
+ol.geom2.LineStringCollection = function(buf, opt_ranges, opt_dim) {
+
+  /**
+   * @type {ol.structs.Buffer}
+   */
+  this.buf = buf;
+
+  /**
+   * @type {Object.<number, Array.<number>>}
+   */
+  this.ranges = goog.isDef(opt_ranges) ? opt_ranges : {};
+
+  /**
+   * @type {number}
+   */
+  this.dim = goog.isDef(opt_dim) ? opt_dim : 2;
+
+};
+
+
+/**
+ * @param {number} capacity Capacity.
+ * @param {number=} opt_dim Dimension.
+ * @return {ol.geom2.LineStringCollection} Line string collection.
+ */
+ol.geom2.LineStringCollection.createEmpty = function(capacity, opt_dim) {
+  var dim = goog.isDef(opt_dim) ? opt_dim : 2;
+  var buf = new ol.structs.Buffer(new Array(capacity * dim), 0);
+  return new ol.geom2.LineStringCollection(buf, undefined, dim);
+};
+
+
+/**
+ * @param {Array.<ol.geom2.LineString>} unpackedLineStrings Unpacked line
+ *     strings.
+ * @param {number=} opt_capacity Capacity.
+ * @param {number=} opt_dim Dimension.
+ * @return {ol.geom2.LineStringCollection} Line string collection.
+ */
+ol.geom2.LineStringCollection.pack =
+    function(unpackedLineStrings, opt_capacity, opt_dim) {
+  var i;
+  var n = unpackedLineStrings.length;
+  var dim = goog.isDef(opt_dim) ? opt_dim :
+      n > 0 ? unpackedLineStrings[0][0].length : 2;
+  var capacity;
+  if (goog.isDef(opt_capacity)) {
+    capacity = opt_capacity;
+  } else {
+    capacity = 0;
+    for (i = 0; i < n; ++i) {
+      capacity += unpackedLineStrings[i].length;
+    }
+  }
+  capacity *= dim;
+  var arr = new Array(capacity);
+  /** @type {Object.<number, Array.<number>>} */
+  var ranges = {};
+  var offset = 0;
+  var start;
+  for (i = 0; i < n; ++i) {
+    goog.asserts.assert(unpackedLineStrings[i].length > 1);
+    start = offset;
+    offset = ol.geom2.packPoints(arr, offset, unpackedLineStrings[i], dim);
+    ranges[start] = [start, offset];
+  }
+  goog.asserts.assert(offset <= capacity);
+  var buf = new ol.structs.Buffer(arr, offset);
+  return new ol.geom2.LineStringCollection(buf, ranges, dim);
+};
+
+
+/**
+ * @param {ol.geom2.LineString} lineString Line string.
+ * @return {number} Offset.
+ */
+ol.geom2.LineStringCollection.prototype.add = function(lineString) {
+  var n = lineString.length * this.dim;
+  var offset = this.buf.allocate(n);
+  goog.asserts.assert(offset != -1);
+  this.ranges[offset] = [offset, offset + n];
+  ol.geom2.packPoints(this.buf.getArray(), offset, lineString, this.dim);
+  return offset;
+};
+
+
+/**
+ * @param {number} offset Offset.
+ * @return {ol.geom2.LineString} Line string.
+ */
+ol.geom2.LineStringCollection.prototype.get = function(offset) {
+  goog.asserts.assert(offset in this.ranges);
+  var range = this.ranges[offset];
+  return ol.geom2.unpackPoints(
+      this.buf.getArray(), range[0], range[1], this.dim);
+};
+
+
+/**
+ * @return {number} Count.
+ */
+ol.geom2.LineStringCollection.prototype.getCount = function() {
+  return goog.object.getCount(this.ranges);
+};
+
+
+/**
+ * @return {ol.Extent} Extent.
+ */
+ol.geom2.LineStringCollection.prototype.getExtent = function() {
+  return ol.geom2.getExtent(this.buf, this.dim);
+};
+
+
+/**
+ * @param {number} offset Offset.
+ */
+ol.geom2.LineStringCollection.prototype.remove = function(offset) {
+  goog.asserts.assert(offset in this.ranges);
+  var range = this.ranges[offset];
+  this.buf.remove(range[1] - range[0], range[0]);
+  delete this.ranges[offset];
+};
+
+
+/**
+ * @param {number} offset Offset.
+ * @param {ol.geom2.LineString} lineString Line string.
+ * @return {number} Offset.
+ */
+ol.geom2.LineStringCollection.prototype.set = function(offset, lineString) {
+  var dim = this.dim;
+  goog.asserts.assert(offset in this.ranges);
+  var range = this.ranges[offset];
+  if (lineString.length * dim == range[1] - range[0]) {
+    ol.geom2.packPoints(this.buf.getArray(), range[0], lineString, dim);
+    this.buf.markDirty(range[1] - range[0], range[0]);
+    return offset;
+  } else {
+    this.remove(offset);
+    return this.add(lineString);
+  }
+};
+
+
+/**
+ * @return {Array.<ol.geom2.LineString>} Line strings.
+ */
+ol.geom2.LineStringCollection.prototype.unpack = function() {
+  var dim = this.dim;
+  var n = this.getCount();
+  var lineStrings = new Array(n);
+  var i = 0;
+  var offset, range;
+  for (offset in this.ranges) {
+    range = this.ranges[Number(offset)];
+    lineStrings[i++] = ol.geom2.unpackPoints(
+        this.buf.getArray(), range[0], range[1], dim);
+  }
+  return lineStrings;
+};