[Kstars-devel] SkyMap surprise (Quaternions are not used in fact)

[Médéric Boquien]

Hi,

On Thursday 05 November 2009 17:27:20 Khudyakov Alexey wrote:
> I just found out that quaternions are not used in KStars code. Only place
> where function SkyMap::toScreenQuaternion is referenced is debug code and
> it's only user of quaternion related stuff.
>
> However these unused quaternions are not free at all. Each SkyPoint contain
> its quaternion representation (16 bytes wasted) and keeps it in sync which
> means wasted CPU cycles. (involve relatively costly trigonometric
> functions)
>
> Therefore I propose to remove quaternion-related code from KStars
> completely.

The better solution would probably go quaternions all the way. They should be 
significantly faster than the current method. I guess this is a remnant of a 
first attempt that has never been completed. But that's a lot of work. So in 
the meantime it is probably a waste, indeed.

Médéric