cesium入門（八）

互動

• 我們可以通過三種方式來通過滑鼠和cesium互動
  
  1. scene.pick 通過視窗座標來取一個物件
  2. scene.drillPick取一個物件列表
  3. Globe.pick 根據光線和地形取一個物件

 // If the mouse is over a point of interest, change the entity billboard scale and color
    var previousPickedEntity;
    var handler = viewer.screenSpaceEventHandler
 
;
    //監聽操作型別和處理函式
    handler.setInputAction(function (movement) {
        var pickedPrimitive = viewer.scene.pick(movement.endPosition);
        var pickedEntity = Cesium.defined(pickedPrimitive) ? pickedPrimitive.id : undefined;
        // Unhighlight the previously picked entity
        if (Cesium.defined
 
(previousPickedEntity)) {
            previousPickedEntity.billboard.scale = 1.0;
            previousPickedEntity.billboard.color = Cesium.Color.WHITE;
        }
        // Highlight the currently picked entity
        if (Cesium.defined(pickedEntity) && Cesium.defined(pickedEntity.billboard)) {
            pickedEntity.billboard
 
.scale = 2.0;
            pickedEntity.billboard.color = Cesium.Color.ORANGERED;
            previousPickedEntity = pickedEntity;
        }
    }, Cesium.ScreenSpaceEventType.MOUSE_MOVE);

相機模型

• 兩種一種是靜態的也是預設的給那在那，第二種是動態的可以自動根據參照物調整

// Create a follow camera by tracking the drone entity
function setViewMode() {
    if (droneModeElement.checked) {
    //自動跟
        viewer.trackedEntity = drone;
    } else {
    //取消第一步先給值underfined第二個飛回預設
        viewer.trackedEntity = undefined;
        viewer.scene.camera.flyTo(homeCameraView);
    }
}
var freeModeElement = document.getElementById('freeMode');
    var droneModeElement = document.getElementById('droneMode');

    // Create a follow camera by tracking the drone entity
    function setViewMode() {
        if (droneModeElement.checked) {
            viewer.trackedEntity = drone;
        } else {
            viewer.trackedEntity = undefined;
            viewer.scene.camera.flyTo(homeCameraView);
        }
    }

    freeModeElement.addEventListener('change', setViewMode);
    droneModeElement.addEventListener('change', setViewMode);

    viewer.trackedEntityChanged.addEventListener(function() {
        if (viewer.trackedEntity === drone) {
            freeModeElement.checked = false;
            droneModeElement.checked = true;
        }
    });

展現

-我們可以通過entity控制單個的，同樣我們也可以控制它周邊的。如下一般用不到沒有研究

var shadowsElement = document.getElementById('shadows');
    var neighborhoodsElement =  document.getElementById('neighborhoods');

    shadowsElement.addEventListener('change', function (e) {
        viewer.shadows = e.target.checked;
    });

    neighborhoodsElement.addEventListener('change', function (e) {
        neighborhoods.show = e.target.checked;
    });

    // Finally, wait for the initial city to be ready before removing the loading indicator.
    var loadingIndicator = document.getElementById('loadingIndicator');
    loadingIndicator.style.display = 'block';
    city.readyPromise.then(function () {
        loadingIndicator.style.display = 'none';
    });