Space Features

• Ability to show Earth-centered view in ICRF instead of Fixed. - #825
• Draw planes perpendicular to orbits
• Stored views per track
• Render moon and other planets
• Sun centered views (Should ultimately support any CB as the center)
• Sensor improvements
  • Narrow six-arc-second field-of-view. Display condition to draw a polyline?
  • Narrow sensor like a fan
  • Wide sensor with a cap
  • Billboard aligned with sensor boresight (use a model?)
  • Draw a cone from the Sun to Earth's silhouette. Compute custom sensor?

Done

• Viewing in LLVH - #531 #818
• Render sun.
• More precise sun position. #391
• Inertial frame
• Polyline - per-vertex color for passes. Will [materials] (https://github.com/AnalyticalGraphicsInc/cesium/wiki/Fabric) on polylines work?
• Ellipsoid improvements
  • Eliminate jitter - #392
  • Zoom inside - #390
  • Covariance interpolation (in czml-writer)