Bug 414216

Summary:	constellation names and boundaries move in respect to constellations for dates centuries ago
Product:	[Applications] kstars	Reporter:	Heiko Evermann <heiko.evermann>
Component:	general	Assignee:	Jasem Mutlaq <mutlaqja>
Status:	CONFIRMED ---
Severity:	normal	CC:	eric.dejouhanet
Priority:	NOR
Version First Reported In:	3.4.1
Target Milestone:	---
Platform:	Other
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Heiko Evermann 2019-11-16 21:00:25 UTC

SUMMARY
When going back a long time ago, e.g. 500 BC, then the constellation names and constellation boundaries move in respect to the constellations. They are no longer within their boundaries. The names however still match the constallation boundaries. 

STEPS TO REPRODUCE
1. start kstars, show constellation boundaries and names
2. enter year= -500
3. go

OBSERVED RESULT
constellation boundaries no longer match the constellations

EXPECTED RESULT
they still should


SOFTWARE/OS VERSIONS
Windows: current binaries
macOS: 
Linux/KDE Plasma: current ubuntu
(available in About System)
KDE Plasma Version: 
KDE Frameworks Version: 
Qt Version: 

ADDITIONAL INFORMATION

Comment 1 TallFurryMan 2020-04-16 20:15:31 UTC

Constellations are located with a RA/DEC mid-point that is unrelated to stars actually. That mid-point is used to render the constellation art in the sky representation.

SkyQPainter::drawConstellationArtImage only uses EquatorialToHorizontal to compute the position of the image, thus locate the drawing in J2000. So, yes, bug confirmed for me.