[Update: this issue has now been fixed, see my followup post]
I’ve been playing with importing horizon data into PiAware from HeyWhatsThat and I’ve noticed a discrepancy in the scale of the horizon when displayed in Skyview. The effect is more noticeable at higher (and presumably lower) latitudes and less so towards the equator. Has anyone else noticed this? I have contacted HWT but thought I’d make people here aware too and see if there’s any feedback.
Here’s an example.
I went to https://www.heywhatsthat.com/?refraction=1 and created a new panorama with an index of 0.25. I centered it on part of Poland’s northern coast at an elevation of 5 metres above the ground.
The panorama is completed with ID MAVVN9WW [Edit: I have also tried this with elevation set to 0 metres in panorama NQTF4WQB, after ensuring old data was not cached the result was identical to the original]. I have it display a horizon for an altitude of 12192 metres. You can see that shown in blue.
I import the JSON data with the same parameters and move it into the relevant subdirectory.
I view the horizon in Skyview.
Notice that, while it is the correct shape and item, it has a different scaling on each map. On HWT it just passes Copenhagen; on Skyview it goes right past it. On HWT it intersects Warsaw; on Skyview it goes past it. On HWT it doesn’t reach Riga, Latvia’s capital; on Skyview it goes past it. The horizon is around 50 statute miles further out in all directions on Skyview than it is on HWT.
I’m trying to get to the bottom of whether this is:
- A bug in the way the horizon is shown on the HWT map
- A bug in the way the horizon is shown on the Skyview map
- A bug in the generation of the JSON data
- Something else
I’ll update if HWT responds.