Generating ghost billboards on timeinterval limits - how do intervals merge?


In our product we represent ending time series by showing an entity’s billboard faded for a given period immediately before and after the effective data samples. As such, first our data shows up as faded icons, then the real data kicks in and we show them moving in full color, and finally they show up faded again when the data series ends.

As of now, we’re generating CZML with three distinct intervals, changing the billboard’s color alpha accordingly to represent those 3 time segments.

Nonetheless, as we changed our data backend, we’d like to real-time stream our new positions to the web client where Cesium runs, and most of those new positions impact the final interval, when the entity fades to the end.

Thus, two questions:

  1. while sending CZML sampled data back to cesium and partially overlapping intervals, how does Cesium manage the intersections, and do the new data points eat away the previous ones?

  2. Is there a simple way to perform (out of the box or customizing Cesium) in order for a given entity to stay still and displayed x amount of time after its data source’s data availability?