CesiumGS · mramato · Mar 20, 2018 · Mar 9, 2018 · Mar 14, 2018 · Mar 14, 2018
diff --git a/Apps/Sandcastle/gallery/DataSource Ordering.html b/Apps/Sandcastle/gallery/DataSource Ordering.html
@@ -0,0 +1,127 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="utf-8">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, minimum-scale=1, user-scalable=no">
+    <meta name="description" content="Change the order in which DataSources draw ground primitives">
+    <meta name="cesium-sandcastle-labels" content="DataSources">
+    <title>Cesium Demo</title>
+    <script type="text/javascript" src="../Sandcastle-header.js"></script>
+    <script type="text/javascript" src="../../../ThirdParty/requirejs-2.1.20/require.js"></script>
+    <script type="text/javascript">
+        if(typeof require === "function") {
+            require.config({
+                baseUrl : '../../../Source',
+                waitSeconds : 120
+            });
+        }
+    </script>
+</head>
+<body class="sandcastle-loading" data-sandcastle-bucket="bucket-requirejs.html">
+<style>
+    @import url(../templates/bucket.css);
+</style>
+<div id="cesiumContainer" class="fullSize"></div>
+<div id="loadingOverlay"><h1>Loading...</h1></div>
+<div id="toolbar"></div>
+<script id="cesium_sandcastle_script">
+function startup(Cesium) {
+    'use strict';
+//Sandcastle_Begin
+var czml1 = [{
+    "id" : "document",
+    "name" : "CZML Geometries: Rectangle",
+    "version" : "1.0"
+}, {
+    "rectangle" : {
+        "coordinates" : {
+            "wsenDegrees" : [-120, 40, -110, 50]
+        },
+        "fill" : true,
+        "material" : {
+            "solidColor" : {
+                "color": {
+                    "rgba" : [255, 0, 0, 255]
+                }
+            }
+        }
+    }
+}, {
+    "rectangle" : {
+        "coordinates" : {
+            "wsenDegrees" : [-110, 40, -100, 50]
+        },
+        "fill" : true,
+        "material" : {
+            "solidColor" : {
+                "color": {
+                    "rgba" : [0, 0, 255, 255]
+                }
+            }
+        }
+    }
+}];
+
+var czml2 = [{
+    "id" : "document",
+    "name" : "CZML Geometries: Rectangle",
+    "version" : "1.0"
+}, {
+    "rectangle" : {
+        "coordinates" : {
+            "wsenDegrees" : [-120, 45, -110, 55]
+        },
+        "fill" : true,
+        "material" : {
+            "solidColor" : {
+                "color": {
+                    "rgba" : [255, 255, 0, 255]
+                }
+            }
+        }
+    }
+}, {
+    "rectangle" : {
+        "coordinates" : {
+            "wsenDegrees" : [-110, 45, -100, 55]
+        },
+        "fill" : true,
+        "material" : {
+            "solidColor" : {
+                "color": {
+                    "rgba" : [0, 255, 255, 255]
+                }
+            }
+        }
+    }
+}];
+
+var viewer = new Cesium.Viewer('cesiumContainer');
+var promise1 = Cesium.CzmlDataSource.load(czml1);
+viewer.dataSources.add(promise1);
+var promise2 = Cesium.CzmlDataSource.load(czml2);
+viewer.dataSources.add(promise2);
+
+Sandcastle.addToolbarButton('Swap', function() {
+    Cesium.when.all([promise1, promise2])
+    .then(function(results) {
+        var ds1 = results[0];
+        var ds2 = results[1];
+        if (viewer.dataSources.indexOf(ds1) === 0) {
+            viewer.dataSources.raise(ds1);
+        } else {
+            viewer.dataSources.lower(ds1);
+        }
+    });
+});//Sandcastle_End
+    Sandcastle.finishedLoading();
+}
+if (typeof Cesium !== "undefined") {
+    startup(Cesium);
+} else if (typeof require === "function") {
+    require(["Cesium"], startup);
+}
+</script>
+</body>
+</html>
diff --git a/Apps/Sandcastle/gallery/DataSource Ordering.jpg b/Apps/Sandcastle/gallery/DataSource Ordering.jpg
diff --git a/CHANGES.md b/CHANGES.md
@@ -3,6 +3,9 @@ Change Log
 
 ### 1.44 - 2018-04-02
 
+##### Breaking Changes :mega:
+* `GeometryVisualizer` now requires `primitive` and `groundPrimitive` parameters. [#6316](https://github.com/AnalyticalGraphicsInc/cesium/pull/6316)
+
 ##### Deprecated :hourglass_flowing_sand:
 * `ClippingPlaneCollection` is now supported in Internet Explorer, so `ClippingPlaneCollection.isSupported` has been deprecated and will be removed in Cesium 1.45.
 * `ClippingPlaneCollection` should now be used with `ClippingPlane` objects instead of `Plane`. Use of `Plane` objects has been deprecated and will be removed in Cesium 1.45.
@@ -19,6 +22,9 @@ Change Log
   * sourceType specifies the type of data source if the URL doesn't have a known file extension.
   * flyTo=false optionally disables the automatic flyTo after loading the data source.
 * Added a multi-part CZML example to Sandcastle. [#6320](https://github.com/AnalyticalGraphicsInc/cesium/pull/6320)
+* Added support for ordering in `DataSourceCollection` [#6316](https://github.com/AnalyticalGraphicsInc/cesium/pull/6316)
+  * All ground geometry from one `DataSource` will render in front of all ground geometry from another `DataSource` in the same collection with a lower index.
+  * Use `DataSourceCollection.raise`, `DataSourceCollection.lower`, `DataSourceCollection.raiseToTop` and `DataSourceCollection.lowerToBottom` functions to change the ordering of a `DataSource` in the collection. 
 
 ##### Fixes :wrench:
 * Fixed support of glTF-supplied tangent vectors. [#6302](https://github.com/AnalyticalGraphicsInc/cesium/pull/6302)

diff --git a/Source/DataSources/DataSourceCollection.js b/Source/DataSources/DataSourceCollection.js
@@ -5,6 +5,7 @@ define([
         '../Core/destroyObject',
         '../Core/DeveloperError',
         '../Core/Event',
+        '../Core/Math',
         '../ThirdParty/when'
     ], function(
         defaultValue,
@@ -13,6 +14,7 @@ define([
         destroyObject,
         DeveloperError,
         Event,
+        CesiumMath,
         when) {
     'use strict';
 
@@ -25,6 +27,7 @@ define([
         this._dataSources = [];
         this._dataSourceAdded = new Event();
         this._dataSourceRemoved = new Event();
+        this._dataSourceMoved = new Event();
     }
 
     defineProperties(DataSourceCollection.prototype, {
@@ -64,6 +67,19 @@ define([
             get : function() {
                 return this._dataSourceRemoved;
             }
+        },
+
+        /**
+         * An event that is raised when a data source changes position in the collection.  Event handlers are passed the data source
+         * that was moved, its new index after the move, and its old index prior to the move.
+         * @memberof DataSourceCollection.prototype
+         * @type {Event}
+         * @readonly
+         */
+        dataSourceMoved : {
+            get : function() {
+                return this._dataSourceMoved;
+            }
         }
     });
 
@@ -177,6 +193,105 @@ define([
         return this._dataSources[index];
     };
 
+    function getIndex(dataSources, dataSource) {
+        //>>includeStart('debug', pragmas.debug);
+        if (!defined(dataSource)) {
+            throw new DeveloperError('dataSource is required.');
+        }
+        //>>includeEnd('debug');
+
+        var index = dataSources.indexOf(dataSource);
+
+        //>>includeStart('debug', pragmas.debug);
+        if (index === -1) {
+            throw new DeveloperError('dataSource is not in this collection.');
+        }
+        //>>includeEnd('debug');
+
+        return index;
+    }
+
+    function swapDataSources(collection, i, j) {
+        var arr = collection._dataSources;
+        var length = arr.length - 1;
+        i = CesiumMath.clamp(i, 0, length);
+        j = CesiumMath.clamp(j, 0, length);
+
+        if (i === j) {
+            return;
+        }
+
+        var temp = arr[i];
+        arr[i] = arr[j];
+        arr[j] = temp;
+
+        collection.dataSourceMoved.raiseEvent(temp, j, i);
+    }
+
+    /**
+     * Raises a data source up one position in the collection.
+     *
+     * @param {DataSource} dataSource The data source to move.
+     *
+     * @exception {DeveloperError} dataSource is not in this collection.
+     * @exception {DeveloperError} This object was destroyed, i.e., destroy() was called.
+     */
+    DataSourceCollection.prototype.raise = function(dataSource) {
+        var index = getIndex(this._dataSources, dataSource);
+        swapDataSources(this, index, index + 1);
+    };
+
+    /**
+     * Lowers a data source down one position in the collection.
+     *
+     * @param {DataSource} dataSource The data source to move.
+     *
+     * @exception {DeveloperError} dataSource is not in this collection.
+     * @exception {DeveloperError} This object was destroyed, i.e., destroy() was called.
+     */
+    DataSourceCollection.prototype.lower = function(dataSource) {
+        var index = getIndex(this._dataSources, dataSource);
+        swapDataSources(this, index, index - 1);
+    };
+
+    /**
+     * Raises a data source to the top of the collection.
+     *
+     * @param {DataSource} dataSource The data source to move.
+     *
+     * @exception {DeveloperError} dataSource is not in this collection.
+     * @exception {DeveloperError} This object was destroyed, i.e., destroy() was called.
+     */
+    DataSourceCollection.prototype.raiseToTop = function(dataSource) {
+        var index = getIndex(this._dataSources, dataSource);
+        if (index === this._dataSources.length - 1) {
+            return;
+        }
+        this._dataSources.splice(index, 1);
+        this._dataSources.push(dataSource);
+
+        this.dataSourceMoved.raiseEvent(dataSource, this._dataSources.length - 1, index);
+    };
+
+    /**
+     * Lowers a data source to the bottom of the collection.
+     *
+     * @param {DataSource} dataSource The data source to move.
+     *
+     * @exception {DeveloperError} dataSource is not in this collection.
+     * @exception {DeveloperError} This object was destroyed, i.e., destroy() was called.
+     */
+    DataSourceCollection.prototype.lowerToBottom = function(dataSource) {
+        var index = getIndex(this._dataSources, dataSource);
+        if (index === 0) {
+            return;
+        }
+        this._dataSources.splice(index, 1);
+        this._dataSources.splice(0, 0, dataSource);
+
+        this.dataSourceMoved.raiseEvent(dataSource, 0, index);
+    };
+
     /**
      * Returns true if this object was destroyed; otherwise, false.
      * If this object was destroyed, it should not be used; calling any function other than