Entity Polygon Alpha Flickering

CesiumJS
1

Hi,

I’m trying to add multiple entities to a datasource, each one containing a polygon with an alpha value set, however when a new entity is added the alpha values for all the other polygons in the collection appear to flicker or flash to 100% briefly before returning to their original values.

var viewer = new Cesium.Viewer(‘cesiumContainer’);

var dataSource = new Cesium.CustomDataSource(‘Polygons’);
viewer.dataSources.add(dataSource);

var x = 0;
var y = 0;

setInterval(function(){
x += 5;
y += 2;

var area = [0 + y, 51 + x, 5 + y, 51 + x, 2.50 + y, 48 + x];

dataSource.entities.add({
name: ‘test’,
show : true,
polygon : {
hierarchy :{
positions: Cesium.Cartesian3.fromDegreesArray(area)
},
material : Cesium.Color.RED.withAlpha(0.5)
}
});
}, 1000);

``

In the full code being used in our application I’m trying to fade the polygons out over time (as per the advice in https://groups.google.com/forum/#!newtopic/cesium-dev/cesium-dev/kbTxKXbRF44) - but it still seems to occur when using a solid colour too.

Also from what I can tell this doesn’t appear to be the case for other types in an entity, for example polylines or billboards.

Many Thanks,

Oliver

2

Hello Oliver,

Thanks for including the code sample! I was able to reproduce this on my machine. I submitted an issue to our Github: https://github.com/AnalyticalGraphicsInc/cesium/issues/3945

Best,

Hannah

3

Hello,

This has been fixed and will be available in the Cesium 1.45 release available on May 1st.

Thanks!

Hannah