Cesium Click to obtain the longitude and latitude elevation coordinates (3D coordinates) of the model surface

The following code applies to Model surface Three dimensional coordinates .

Be careful ：

1. The following code only applies to models 、 Acquisition of surface coordinates such as tilt photography （ Terrain three-dimensional coordinates of my other articles ）
2. Depth detection needs to be turned on depthTestAgainstTerrain = true.

//  Open depth detection 
viewer.scene.globe.depthTestAgainstTerrain = true

var handler = new Cesium.ScreenSpaceEventHandler(gvEarth.scene.canvas);
handler.setInputAction(function (evt) {
    
  var scene = gvEarth.scene;
  //  Judge the mode of the scene , It can't be   Deformation mode 
  if (scene.mode !== Cesium.SceneMode.MORPHING) {
    
    // scene.pick:  return scene At the top of the specified position in primitive An object of property 
    let pickedObject = scene.pick(evt.position);
    //  Determine if the model is picked up 
    if (scene.pickPositionSupported && Cesium.defined(pickedObject) && pickedObject.node) {
    
      let cartesian = gvEarth.scene.pickPosition(evt.position);
      //  Whether spatial coordinates are obtained 
      if (Cesium.defined(cartesian)) {
    
        // //  Space coordinates to world coordinates ( radian )
        let cartographic = Cesium.Cartographic.fromCartesian(cartesian);
        //  Radian to angle （ Longitude and latitude ）
        let lon = Cesium.Math.toDegrees(cartographic.longitude);
        let lat = Cesium.Math.toDegrees(cartographic.latitude);
        // Model height 
        let height = cartographic.height;  
        console.log(' The longitude and latitude elevation of the model surface is ：', {
     x: lon, y: lat, height: height })
      }
    }
  }
}, Cesium.ScreenSpaceEventType.LEFT_CLICK);

Explain ：

viewer.scene.pickPosition(e.position) In the absence of 3dTile The problem of Cartesian coordinates inaccuracy under the model , It can be solved by opening depth detection viewer.scene.globe.depthTestAgainstTerrain = true

viewer.scene.pick： return scene At the top of the specified position in primitive An object of property . Applicable to selection 3dTile, change 3dTile Properties of （ Such as color ）.

viewer.scene.pickPosition： Returns a point specified by the screen coordinates and depth cache . It is applicable to the selection of model surface position , Generally speaking, it means camera Look at the first blocked model （ Such as entity） The coordinates on , Usually combined with other selection methods, it is used to select the points on the model and ball （ combination viewer.scene.pick Use together ）.