bad projected screen coordinates in Equatorial mode
See forum topic https://indilib.org/forum/general/12339-artificial-horizon-gone-bonkers.html#86540 and I've confirmed this--easy to repeat.
I tried to trace down the bad rendering of the horizon, and found that inside SkyQPainter::drawSkyPolygon() m_proj->toScreen(point.get(), false, &isVisibleLast); was returning bad values in equatorial mode. E.g. here's an output from horizon mode where the first line is a list of az,alt values and the coords line is a list of x,y screen coordinates:
drawSkyPolygon(drawSkyPolygon((10.0 90.0)(10.0 88.0)(10.0 86.0)(10.0 84.0)(10.0 82.0)(10.0 80.0)(10.0 80.0)(11.0 80.0)(11.0 80.0)(11.0 82.0)(11.0 84.0)(11.0 86.0)(11.0 88.0)(11.0 90.0)(11.0 90.0)(10.0 90.0) F coords: (352.0 259.2)(348.7 271.0)(345.4 282.9)(342.2 294.9)(339.0 306.9)(335.8 318.9)(335.8 318.9)(336.8 319.2)(336.8 319.2)(339.8 307.1)(342.8 295.0)(345.9 283.0)(348.9 271.1)(352.0 259.2)(352.0 259.2)(352.0 259.2)
and the same polygon in equatorial mode (pressing space on the skymap shows a much distorted polygon
drawSkyPolygon(drawSkyPolygon((10.0 90.0)(10.0 88.0)(10.0 86.0)(10.0 84.0)(10.0 82.0)(10.0 80.0)(10.0 80.0)(11.0 80.0)(11.0 80.0)(11.0 82.0)(11.0 84.0)(11.0 86.0)(11.0 88.0)(11.0 90.0)(11.0 90.0)(10.0 90.0) F coords: (286.7 -153.3)(485.5 503.3)(477.1 494.3)(468.6 485.3)(460.0 476.3)(451.4 467.3)(286.7 -153.3)(450.7 468.1)(286.7 -153.3)(459.4 476.9)(468.1 485.8)(476.8 494.6)(485.4 503.5)(493.9 512.3)(493.9 512.3)(286.7 -153.3)