Start of display conditions

Source/DataSources/ModelVisualizer.js

@@ -5,10 +5,12 @@ define([
         '../Core/defined',
         '../Core/destroyObject',
         '../Core/DeveloperError',
+        '../Core/Math',
         '../Core/Matrix3',
         '../Core/Matrix4',
         '../Core/Quaternion',
         '../Core/Transforms',
+        '../Scene/DistanceDisplayCondition',
         '../Scene/Model',
         '../Scene/ModelAnimationLoop',
         './Property'
@@ -18,10 +20,12 @@ define([
         defined,
         destroyObject,
         DeveloperError,
+        CesiumMath,
         Matrix3,
         Matrix4,
         Quaternion,
         Transforms,
+        DistanceDisplayCondition,
         Model,
         ModelAnimationLoop,
         Property) {
@@ -114,7 +118,9 @@ define([
                     delete modelHash[entity.id];
                 }
                 model = Model.fromGltf({
-                    url : uri
+                    url : uri,
+                    displayCondition : new DistanceDisplayCondition(0, 1000.0),
+                    loadOnlyIfDisplayCondition : true
                 });
 
                 model.readyToRender.addEventListener(readyToRender, this);
@@ -138,9 +144,11 @@ define([
             orientation = Property.getValueOrUndefined(entity._orientation, time, orientation);
             if (!Cartesian3.equals(position, modelData.position) || !Quaternion.equals(orientation, modelData.orientation)) {
                 if (!defined(orientation)) {
-                    Transforms.eastNorthUpToFixedFrame(position, scene.globe.ellipsoid, model.modelMatrix);
+//                    Transforms.eastNorthUpToFixedFrame(position, scene.globe.ellipsoid, model.modelMatrix);
+                    Transforms.northEastDownToFixedFrame(position, scene.globe.ellipsoid, model.modelMatrix);
+                    Matrix4.multiplyByMatrix3(model.modelMatrix, Matrix3.fromRotationZ(CesiumMath.toRadians(90.0)), model.modelMatrix);
                 } else {
-                    Matrix4.fromRotationTranslation(Matrix3.fromQuaternion(orientation, matrix3Scratch), position, model.modelMatrix);
+//                    Matrix4.fromRotationTranslation(Matrix3.fromQuaternion(orientation, matrix3Scratch), position, model.modelMatrix);
                 }
                 modelData.position = Cartesian3.clone(position, modelData.position);
                 modelData.orientation = Quaternion.clone(orientation, modelData.orientation);

Source/Scene/DistanceDisplayCondition.js

@@ -0,0 +1,73 @@
+/*global define*/
+define([
+        '../Core/Cartesian3',
+        '../Core/defaultValue',
+        '../Core/defineProperties',
+        '../Core/Matrix4'
+    ], function(
+        Cartesian3,
+        defaultValue,
+        defineProperties,
+        Matrix4) {
+    "use strict";
+
+    /**
+     * DOC_TBA
+     *
+     * @alias DistanceDisplayCondition
+     * @constructor
+     */
+    var DistanceDisplayCondition = function(near, far) {
+        /**
+         * DOC_TBA
+         */
+        near = defaultValue(near, 0.0);
+        this._near = near;
+        this._near2 = near * near;
+
+        /**
+         * DOC_TBA
+         */
+        far = defaultValue(far, Number.MAX_VALUE);
+        this._far = far;
+        this._far2 = far * far;
+    };
+
+    defineProperties(DistanceDisplayCondition.prototype, {
+        near : {
+            get : function() {
+                return this._near;
+            },
+            set : function(value) {
+                this._near = value;
+                this._near2 = value * value;
+            }
+        },
+
+        far : {
+            get : function() {
+                return this._far;
+            },
+            set : function(value) {
+                this._far = value;
+                this._far2 = value * value;
+            }
+        }
+    });
+
+    var scratchPosition = new Cartesian3();
+
+    /**
+     * DOC_TBA
+     */
+    DistanceDisplayCondition.prototype.isVisible = function(primitive, frameState) {
+        // TODO: need to consider positions, e.g., for a polyline
+
+        // Distance to center of primitive's reference frame
+        var position = Matrix4.getTranslation(primitive.modelMatrix, scratchPosition);
+        var distance2 = Cartesian3.distanceSquared(position, frameState.camera.positionWC);
+        return (distance2 >= this._near2) && (distance2 <= this._far2);
+    };
+
+    return DistanceDisplayCondition;
+});

Source/Scene/Model.js

@@ -160,6 +160,8 @@ define([
      * @param {Object} [options.gltf] The object for the glTF JSON.
      * @param {String} [options.basePath=''] The base path that paths in the glTF JSON are relative to.
      * @param {Boolean} [options.show=true] Determines if the model primitive will be shown.
+     * @param {DisplayCondition} [options.displayCondition] DOC_TBA
+     * @param {Boolean} [options.loadOnlyIfDisplayCondition] DOC_TBA
      * @param {Matrix4} [options.modelMatrix=Matrix4.IDENTITY] The 4x4 transformation matrix that transforms the model from model to world coordinates.
      * @param {Number} [options.scale=1.0] A uniform scale applied to this model.
      * @param {Number} [options.minimumPixelSize=0.0] The approximate minimum pixel size of the model regardless of zoom.
@@ -193,6 +195,16 @@ define([
          */
         this.show = defaultValue(options.show, true);
 
+        /**
+         * DOC_TBA
+         */
+        this.displayCondition = options.displayCondition;
+
+        /**
+         * DOC_TBA
+         */
+        this.loadOnlyIfDisplayCondition = defaultValue(options.loadOnlyIfDisplayCondition, false);
+
         /**
          * The 4x4 transformation matrix that transforms the model from model to world coordinates.
          * When this is the identity matrix, the model is drawn in world coordinates, i.e., Earth's WGS84 coordinates.
@@ -481,6 +493,8 @@ define([
      * @param {String} options.url The url to the .gltf file.
      * @param {Object} [options.headers] HTTP headers to send with the request.
      * @param {Boolean} [options.show=true] Determines if the model primitive will be shown.
+     * @param {DisplayCondition} [options.displayCondition] DOC_TBA
+     * @param {Boolean} [options.loadOnlyIfDisplayCondition] DOC_TBA
      * @param {Matrix4} [options.modelMatrix=Matrix4.IDENTITY] The 4x4 transformation matrix that transforms the model from model to world coordinates.
      * @param {Number} [options.scale=1.0] A uniform scale applied to this model.
      * @param {Number} [options.minimumPixelSize=0.0] The approximate minimum pixel size of the model regardless of zoom.
@@ -2198,6 +2212,12 @@ define([
             return;
         }
 
+        var displayConditionPassed = defined(this.displayCondition) ? this.displayCondition.isVisible(this, frameState) : true;
+        if (this.loadOnlyIfDisplayCondition && !displayConditionPassed) {
+            // Don't even try to load until the display condition is true
+            return;
+        }
+
         if ((this._state === ModelState.NEEDS_LOAD) && defined(this.gltf)) {
             this._state = ModelState.LOADING;
             this._boundingSphere = computeBoundingSphere(this.gltf);
@@ -2224,7 +2244,7 @@ define([
             }
         }
 
-        var show = this.show && (this.scale !== 0.0);
+        var show = this.show && (this.scale !== 0.0) && displayConditionPassed;
 
         if ((show && this._state === ModelState.LOADED) || justLoaded) {
             var animated = this.activeAnimations.update(frameState) || this._cesiumAnimationsDirty;