Autodesk Forge:通过fitToView()将焦点放在对象上后以编程方式缩小

Question

使用 fitToView(objectIds， model( 选择并聚焦在对象上之后，我想以编程方式缩小相机，而不是通过鼠标事件。

我尝试了以下代码，它能够缩小，但 3D 空间失真了。如果您知道如何正确缩小，请告诉我。

// select and isolate target object
let dbid = [1137]
viewer.impl.visibilityManager.isolate(dbid, viewer.model)
viewer.select(dbid)
//focus on target object
viewer.getAggregateSelection((data) => {
    let rootId = data.selector.getInstanceTree().nodeAccess.rootId
    viewer.fitToView(rootId, viewer.model)
})
//zoom out camera
let cam = viewer.getCamera().perspectiveCamera
cam.zoom *= 0.05
viewer.impl.syncCamera();

Answer 1

您需要更改的不是缩放属性，而是相机位置：

var nav = viewer.navigation
var pos = nav.getPosition()
var target = nav.getTarget()
var viewdir = new THREE.Vector3()
viewdir.subVectors (pos, target).normalize()
// zooms out by 100 along the view direction
viewdir.multiplyScalar (100)
pos.add(viewdir)
nav.setPosition(pos)

Answer 2

您需要更改的不是缩放属性，而是设置相机位置：

let camera = this.viewer3D.getCamera();
viewer.fitToView(dbIds, null, true); //provide your device id to locate
var direction = new THREE.Vector3();
camera.getWorldDirection( direction );
//set distance move the camera forward to your needs (gives value in minus for zoomout)
camera.position.add( direction.multiplyScalar(-15)); 
let fov = viewer.navigation.getVerticalFov();  //or horizontalFov
viewer.navigation.setRequestTransition(true, camera.position,viewer.navigation.getTarget(), fov);
//if not work then try fov + 20,30,40 etc..