Cesium之【高度】量算

//****************************高度测量 第一个点的经纬度，第二个点的高度，两点水平距离为半径************************************************//
 var measureHeight = function (viewer, handler){		
		handler_g = handler = new Cesium.ScreenSpaceEventHandler(viewer.scene._imageryLayerCollection);	
		var positions = [];
		var poly = null;
		var tooltip = document.getElementById("toolTip");
		var height = 0;
		var cartesian = null;
		var floatingPoint;
		tooltip.style.display = "block";
		
		handler.setInputAction(function(movement){
			tooltip.style.left = movement.endPosition.x + 3 + "px";
			tooltip.style.top = movement.endPosition.y - 25 + "px";
			tooltip.innerHTML ='
单击开始，双击结束
';
			cartesian = viewer.scene.pickPosition(movement.endPosition); 
			
			console.log(positions);
			if(positions.length >= 2){
				if (!Cesium.defined(poly)) {
					poly = new PolyLinePrimitive(positions);
				}else{
					positions.pop();					
					positions.push(cartesian);
				}
				height = getHeight(positions);				
			}
		},Cesium.ScreenSpaceEventType.MOUSE_MOVE);
		
		handler.setInputAction(function(movement){
			tooltip.style.display = "none";
			
			cartesian = viewer.scene.pickPosition(movement.position); 
	
			if(positions.length == 0) {
				positions.push(cartesian.clone());
				positions.push(cartesian);

				floatingPoint_g = floatingPoint = viewer.entities.add({
				parent:measure_entities,
				name : '高度',
				position : positions[0],				
				point : {
					pixelSize : 5,
					color : Cesium.Color.RED,
					outlineColor : Cesium.Color.WHITE,
					outlineWidth : 2,
					heightReference:Cesium.HeightReference.none 
					},
				label : {
					text : "0米",
					font : '18px sans-serif',
					fillColor : Cesium.Color.GOLD,
					style: Cesium.LabelStyle.FILL_AND_OUTLINE,
					outlineWidth : 2,
					verticalOrigin : Cesium.VerticalOrigin.BOTTOM,
					pixelOffset : new Cesium.Cartesian2(20, -40)
					}
				});
			}						
			
		}, Cesium.ScreenSpaceEventType.LEFT_CLICK);
		 
		handler.setInputAction(function(movement){
			handler.destroy();
			//positions.pop();//清除移动点			
			tooltip.style.display = "none";
			//viewer_g.entities.remove(floatingPoint);
			// console.log(positions);
			//在三维场景中添加Label
			
			var textDisance = height + "米";
							
			var point1cartographic = Cesium.Cartographic.fromCartesian(positions[0]);
			var point2cartographic = Cesium.Cartographic.fromCartesian(positions[1]);					
			var point_temp= Cesium.Cartesian3.fromDegrees(Cesium.Math.toDegrees(point1cartographic.longitude), Cesium.Math.toDegrees(point1cartographic.latitude),point2cartographic.height);	
			

			viewer.entities.add({
				parent:measure_entities,
				name : '直线距离',
				position : point_temp,			
				point : {
					pixelSize : 5,
					color : Cesium.Color.RED,
					outlineColor : Cesium.Color.WHITE,
					outlineWidth : 2,
					heightReference:Cesium.HeightReference.none 
				},
				label : {
					text : textDisance,
					font : '18px sans-serif',
					fillColor : Cesium.Color.GOLD,
					style: Cesium.LabelStyle.FILL_AND_OUTLINE,
					outlineWidth : 2,
					verticalOrigin : Cesium.VerticalOrigin.BOTTOM,
					pixelOffset : new Cesium.Cartesian2(20, -20)
				}
			});		
		}, Cesium.ScreenSpaceEventType.LEFT_DOUBLE_CLICK );		
	
		function getHeight(_positions){
			var cartographic = Cesium.Cartographic.fromCartesian(_positions[0]);
			var cartographic1 = Cesium.Cartographic.fromCartesian(_positions[1]);
			var height_temp = cartographic1.height - cartographic.height;				
			return height_temp.toFixed(2);    			
		}
	
		var PolyLinePrimitive = (function(){
			function _(positions){
				this.options = {
					parent:measure_entities,
					name:'直线',
					polyline : {					
						show : true,
						positions : [],
						material : Cesium.Color.AQUA    ,
						width : 2						
					},
					ellipse : {
						show : true,
						// semiMinorAxis : 30.0,
						// semiMajorAxis : 30.0,
						// height: 20.0,
						material : Cesium.Color.GREEN.withAlpha(0.5),
						outline : true // height must be set for outline to display
					}
				};
				this.positions = positions;
				this._init();
			}
		
			_.prototype._init = function(){
				var _self = this;
				var _update = function(){	
					var temp_position =[];
					temp_position.push( _self.positions[0]);
					var point1cartographic = Cesium.Cartographic.fromCartesian(_self.positions[0]);
					var point2cartographic = Cesium.Cartographic.fromCartesian(_self.positions[1]);					
					var point_temp= Cesium.Cartesian3.fromDegrees(Cesium.Math.toDegrees(point1cartographic.longitude), Cesium.Math.toDegrees(point1cartographic.latitude),point2cartographic.height);			
					temp_position.push(point_temp);
					console.log(temp_position);
					return temp_position;
				};
				var _update_ellipse = function(){					
					return _self.positions[0];
				};
				var _semiMinorAxis = function(){
					var point1cartographic = Cesium.Cartographic.fromCartesian(_self.positions[0]);
					var point2cartographic = Cesium.Cartographic.fromCartesian(_self.positions[1]);
					/**根据经纬度计算出距离**/
					var geodesic = new Cesium.EllipsoidGeodesic();
					geodesic.setEndPoints(point1cartographic, point2cartographic);
					var s = geodesic.surfaceDistance;
					return s;
				};
				var _height =  function(){
					var height_temp = getHeight(_self.positions);
					return height_temp;
				};
				//实时更新polyline.positions
				 this.options.polyline.positions = new Cesium.CallbackProperty(_update,false);
				this.options.position = new Cesium.CallbackProperty(_update_ellipse,false);
				this.options.ellipse.semiMinorAxis =new Cesium.CallbackProperty(_semiMinorAxis,false);
				 this.options.ellipse.semiMajorAxis = new Cesium.CallbackProperty(_semiMinorAxis,false);
				this.options.ellipse.height =  new Cesium.CallbackProperty(_height,false);
				viewer.entities.add(this.options);
			};
		
			return _;
		})();
	};