I hacked at the ground station implementation for a few tonight. My first goal was to cast a line-of-sight trace from the ground station to the satellite once it becomes visible to the ground station. In order to support this, I added two more options to the ground station configuration:
The first option is a boolean that allows you to toggle line of site visibility. The second option allows you to set the line color. These options apply equally to all ground stations and satellites. This means that any sat that is visible from a particular ground station will have a line of sight drawn towards it. I set up a few sample ground stations and tested it out. Here is a shot of one ground station with the ISS passing overhead.
Here is an example of two satellites having line of sight toward SRMSAT.
After waiting a few, we still see the two sample stations tracking SRMSAT.
And closer to the horizon...
Until... it's over! No more line of sight!
Putting this together was fun but now I am brainstorming better ways to visualize this, without having a bland line. I was thinking that maybe a elliptical fan with a transparency covering the life of the pass would look cleaner. I'll likely implement this then post-back some screenshots for opinions.