Drawing and updating polyline issue

Hi folks,

we use Cesium (v. 1.90.0) in an Angular app to display airplane tracks. They are updated every second. To smoothly display tracks and updates we use a callback-property:

      const aircraftPositionsCallback = () => this.aircraftPositions;
      const aircraftPositionsCallbackProperty = new Cesium.CallbackProperty(aircraftPositionsCallback, false);

      this.polyline = new PolylineGraphics({
        positions: aircraftPositionsCallbackProperty,
        material: ApplicationStyles.OUTLINE_COLOR,
        width: 1,

      this.wall = new WallGraphics({
        positions: aircraftPositionsCallbackProperty,
        outline: false,
        material: ApplicationStyles.SELECTION_COLOR_LIGHT,

Although the wall and the polyline are generated in the same way, we face a display problem with the polyline (see screenshot). As you can see the polyline creates a shortcut. Any idea on this?

Kind Regards,

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We have probably found the problem. The aircraft positions sometimes have duplicates. The WallGraphic can obviously handle duplicates better than the PolylineGraphic. As a solution, we filter duplicate in the backend so that Cesium has less work to do.

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