創(chuàng)建從對(duì)象的位置和半徑以及相機(jī)位置派生的封堵器。封堵器可用于確定其他對(duì)象是否可見或隱藏在由封堵器和相機(jī)位置定義的可見地平線之后。
new Occluder(occluderBoundingSphere, cameraPosition)
Parameters:
Example
// Construct an occluder one unit away from the origin with a radius of one.
var cameraPosition = bmgl.Cartesian3.ZERO;
var occluderBoundingSphere = new bmgl.BoundingSphere(new bmgl.Cartesian3(0, 0, -1), 1);
var occluder = new bmgl.Occluder(occluderBoundingSphere, cameraPosition);Members
cameraPosition : Cartesian3
相機(jī)的位置。
position : Cartesian3
封堵器的位置。
radius : Number
封堵器的半徑。
Methods
(static) computeOccludeePoint(occluderBoundingSphere, occludeePosition, positions) → {Object}
計(jì)算一個(gè)點(diǎn)，該點(diǎn)可用作可見性函數(shù)的遮掩位置。使用半徑為零作為遮擋半徑。通常，用戶計(jì)算用于可見性的對(duì)象周圍的邊界球；但是，也可以計(jì)算一個(gè)點(diǎn)，如果看到/不看到，也會(huì)指示對(duì)象是否可見/不可見。對(duì)于相對(duì)于遮光罩不移動(dòng)且較大的對(duì)象（如一塊地形），更好地調(diào)用此函數(shù)。最好不要這樣稱呼，不要將對(duì)象的邊界球用于衛(wèi)星或地面車輛等對(duì)象。
Parameters:
Example
var cameraPosition = new bmgl.Cartesian3(0, 0, 0);
var occluderBoundingSphere = new bmgl.BoundingSphere(new bmgl.Cartesian3(0, 0, -8), 2);
var occluder = new bmgl.Occluder(occluderBoundingSphere, cameraPosition);
var positions = [new bmgl.Cartesian3(-0.25, 0, -5.3), new bmgl.Cartesian3(0.25, 0, -5.3)];
var tileOccluderSphere = bmgl.BoundingSphere.fromPoints(positions);
var occludeePosition = tileOccluderSphere.center;
var occludeePt = bmgl.Occluder.computeOccludeePoint(occluderBoundingSphere, occludeePosition, positions);Throws
-
DeveloperError :
positions必須至少包含一個(gè)元素。
計(jì)算一個(gè)點(diǎn)，該點(diǎn)可用作矩形中可見性函數(shù)的遮擋位置。
Parameters:
從邊界球體和相機(jī)位置創(chuàng)建遮光罩。
Parameters:
確定封堵器的可見程度（不可見、部分可見或完全可見）。
Parameters:
Example
var sphere1 = new bmgl.BoundingSphere(new bmgl.Cartesian3(0, 0, -1.5), 0.5);
var sphere2 = new bmgl.BoundingSphere(new bmgl.Cartesian3(0, 0, -2.5), 0.5);
var cameraPosition = new bmgl.Cartesian3(0, 0, 0);
var occluder = new bmgl.Occluder(sphere1, cameraPosition);
occluder.computeVisibility(sphere2); //returns Visibility.NONE- Occluder#isVisible
See:
確定遮擋器是否隱藏了一個(gè)球體，即
occludee。
Parameters:
Example
var cameraPosition = new bmgl.Cartesian3(0, 0, 0);
var littleSphere = new bmgl.BoundingSphere(new bmgl.Cartesian3(0, 0, -1), 0.25);
var occluder = new bmgl.Occluder(littleSphere, cameraPosition);
var bigSphere = new bmgl.BoundingSphere(new bmgl.Cartesian3(0, 0, -3), 1);
occluder.isBoundingSphereVisible(bigSphere); //returns true
確定遮擋器是否隱藏了一個(gè)點(diǎn)，即
occludee。