From 1a63bf078fdd313d9bbb90b6aa19aacc078c957f Mon Sep 17 00:00:00 2001
From: Tim Schaub <tim.schaub@gmail.com>
Date: Mon, 21 Jan 2013 17:59:09 -0700
Subject: [PATCH] Basic vector source and layer

The vector source maintains a cache of features.  These are indexed by geometry type in anticipation of the renderer's needs.
---
 src/ol/layer/vectorlayer.js   |  24 +++++
 src/ol/source/vectorsource.js | 178 ++++++++++++++++++++++++++++++++++
 2 files changed, 202 insertions(+)
 create mode 100644 src/ol/layer/vectorlayer.js
 create mode 100644 src/ol/source/vectorsource.js

diff --git a/src/ol/layer/vectorlayer.js b/src/ol/layer/vectorlayer.js
new file mode 100644
index 0000000000..acdd8d7f27
--- /dev/null
+++ b/src/ol/layer/vectorlayer.js
@@ -0,0 +1,24 @@
+goog.provide('ol.layer.VectorLayer');
+
+goog.require('ol.layer.Layer');
+goog.require('ol.source.Vector');
+
+
+
+/**
+ * @constructor
+ * @extends {ol.layer.Layer}
+ * @param {ol.layer.LayerOptions} layerOptions Layer options.
+ */
+ol.layer.VectorLayer = function(layerOptions) {
+  goog.base(this, layerOptions);
+};
+goog.inherits(ol.layer.VectorLayer, ol.layer.Layer);
+
+
+/**
+ * @return {ol.source.Vector} Source.
+ */
+ol.layer.VectorLayer.prototype.getVectorSource = function() {
+  return /** @type {ol.source.Vector} */ (this.getSource());
+};
diff --git a/src/ol/source/vectorsource.js b/src/ol/source/vectorsource.js
new file mode 100644
index 0000000000..f6a5fa73a1
--- /dev/null
+++ b/src/ol/source/vectorsource.js
@@ -0,0 +1,178 @@
+goog.provide('ol.source.Vector');
+
+goog.require('ol.Feature');
+goog.require('ol.filter.Filter');
+goog.require('ol.filter.Geometry');
+goog.require('ol.geom.GeometryType');
+goog.require('ol.source.Source');
+
+
+
+/**
+ * @constructor
+ */
+ol.source.FeatureCache = function() {
+
+  /**
+   * @type {Object.<string, ol.Feature>}
+   * @private
+   */
+  this.idLookup_;
+
+
+  /**
+   * @type {Object.<string, Array.<string>>}
+   * @private
+   */
+  this.geometryTypeIndex_;
+
+  this.clear();
+
+};
+
+
+/**
+ * Clear the cache.
+ */
+ol.source.FeatureCache.prototype.clear = function() {
+  this.idLookup_ = {};
+
+  var geometryTypeIndex_ = {};
+  for (var key in ol.geom.GeometryType) {
+    geometryTypeIndex_[ol.geom.GeometryType[key]] = [];
+  }
+  this.geometryTypeIndex_ = geometryTypeIndex_;
+};
+
+
+/**
+ * Add a feature to the cache.
+ * @param {ol.Feature} feature Feature to be cached.
+ */
+ol.source.FeatureCache.prototype.add = function(feature) {
+  var id = goog.getUid(feature).toString(),
+      geometry = feature.getGeometry();
+
+  this.idLookup_[id] = feature;
+
+  // index by geometry type
+  if (!goog.isNull(geometry)) {
+    this.geometryTypeIndex_[geometry.getType()].push(id);
+  }
+
+  /**
+   * TODO: Index by tile coord.  To do this for real requires knowledge about
+   * the evaluated symbolizer literal for each feature.  Initially, a pixel
+   * buffer could be provided.
+   */
+
+};
+
+
+/**
+ * @param {ol.filter.Filter=} opt_filter Optional filter.
+ * @return {Array.<ol.Feature>} Array of features.
+ */
+ol.source.FeatureCache.prototype.getFeatures = function(opt_filter) {
+  var features;
+  if (!goog.isDef(opt_filter)) {
+    features = new Array();
+    for (var id in this.idLookup_) {
+      features.push(this.idLookup_[id]);
+    }
+  } else {
+    if (opt_filter instanceof ol.filter.Geometry) {
+      features = this.getFeaturesByGeometryType_(
+          /** @type {ol.filter.Geometry} */ (opt_filter));
+    } else {
+      // TODO: support other filter types
+      throw new Error('Filter type not supported: ' + opt_filter);
+    }
+  }
+  return features;
+};
+
+
+/**
+ * @param {ol.filter.Geometry} filter Geometry type filter.
+ * @return {Array.<ol.Feature>} Array of features.
+ * @private
+ */
+ol.source.FeatureCache.prototype.getFeaturesByGeometryType_ = function(filter) {
+  var type = filter.getType(),
+      ids = this.geometryTypeIndex_[filter.getType()];
+
+  return this.getFeaturesByIds_(ids);
+};
+
+
+/**
+ * Get features by ids.
+ * @param {Array.<string>} ids Array of (internal) identifiers.
+ * @return {Array.<ol.Feature>} Array of features.
+ * @private
+ */
+ol.source.FeatureCache.prototype.getFeaturesByIds_ = function(ids) {
+  var len = ids.length,
+      features = new Array(len),
+      i;
+  for (i = 0; i < len; ++i) {
+    features[i] = this.idLookup_[ids[i]];
+  }
+  return features;
+};
+
+
+/**
+ * @typedef {{attributions: (Array.<ol.Attribution>|undefined),
+ *            extent: (ol.Extent|undefined),
+ *            projection: (ol.Projection|undefined)}}
+ */
+ol.source.VectorOptions;
+
+
+
+
+/**
+ * @constructor
+ * @extends {ol.source.Source}
+ * @param {ol.source.VectorOptions} options Source options.
+ */
+ol.source.Vector = function(options) {
+
+  goog.base(this, {
+    attributions: options.attributions,
+    extent: options.extent,
+    projection: options.projection
+  });
+
+  /**
+   * @type {ol.source.FeatureCache}
+   * @private
+   */
+  this.featureCache_ = null;
+
+};
+goog.inherits(ol.source.Vector, ol.source.Source);
+
+
+
+/**
+ * @param {Array.<ol.Feature>} features Array of features.
+ */
+ol.source.Vector.prototype.setFeatures = function(features) {
+  this.featureCache_.clear();
+
+  for (var i = 0, ii = features.length; i < ii; ++i) {
+    this.featureCache_.add(features[i]);
+  }
+};
+
+
+/**
+ * @param {ol.filter.Filter=} opt_filter Optional filter.
+ * @return {Array.<ol.Feature>} Array of features.
+ */
+ol.source.Vector.prototype.getFeatures = function(opt_filter) {
+  return this.featureCache_.getFeatures(opt_filter);
+};