model not visible in realtime mode

CesiumJS
1

Hi,

I just upgraded to cesium 1.1 from b28. I have a CZML stream which sends realtime flight information about a UAV. All elements of the UAV (model, point (not emitted in CZML below), label) are only visible, if I am not viewing the UAV in realtime (don't click the clock on the left-bottom). The Path is always visible, though... here's my CZML:

data: [
data: {
data: "id":"document",
data: "version":"1.0"
data: },
data: {
data: "id":"170f4c62-89be-5995-b287-e10e73b2ec51",
data: "name":"UAV",
data: "model":{
data: "gltf":"/Models/UAV/UAV.json",
data: "minimumPixelSize":20,
data: "scale":2,
data: "show":true
data: },
data: "orientation":{
data: "unitQuaternion":[
data: 0.7198903546511335,-0.5759122837209067,0.25916052767440806,-0.2879561418604534
data: ]
data: },
data: "label":{
data: "text":"UAV",
data: "scale":0.8,
data: "eyeOffset":{
data: "cartesian":[
data: 0,-10,0
data: ]
data: }
data: },
data: "path":{
data: "show":true,
data: "width":1,
data: "color":{
data: "rgba":[
data: 255,255,0,255
data: ]
data: },
data: "trailTime":60,
data: "leadTime":0
data: },
data: "position":{
data: "epoch":"2014-09-23T12:09:13.844776Z",
data: "cartographicDegrees":[
data: 0,aa.74308,bb.42744,1,
data: ...
data: 782,aa.7427,bb.42747,18
data: ],
data: "previousTime":"2014-09-23T12:22:19.2677821Z"
data: }
data: }
data: ]

data: {
data: "id":"170f4c62-89be-5995-b287-e10e73b2ec51",
data: "name":"UAV",
data: "position":{
data: "epoch":"2014-09-23T12:28:19.3477442000001Z",
data: "cartographicDegrees":[
data: 0,aa.74263,bb.42746,18
data: ],
data: "previousTime":"2014-09-23T12:22:19.2677821Z"
data: }
data: }

...

2

By default, positions defined in CZML do not extrapolate outside the time interval for which the data is specified. This was a change in CZML 1.0. In your example, the time interval that the position is valid would be “2014-09-23T12:09:13.844776Z” plus 782 seconds. I assume that when you tried it, the current time was after that time interval.

You can configure this by sending down a different value for “forwardExtrapolationType”. http://cesiumjs.org/Cesium/Build/Documentation/ExtrapolationType.html

3

yep, that worked, great, thanks!