[Kstars-devel] RFC: KStars GSOC: data pipelining and OpenCL.

[Aleksey Khudyakov]

On 14 April 2013 02:41, Henry de Valence <hdevalence at gmail.com> wrote:
> On Sat, Apr 13, 2013 at 6:04 PM, Akarsh Simha <akarshsimha at gmail.com> wrote:
>>
>> > AFAIR conversions of coordinates is not worst bottleneck. Last time I
>> > checked (1
>> > or 2 years ago) drawing of constellation lines and borders and
>> > coordinates grid
>> > very much to my surprise. Any proposals to improve performance must be
>> > backed up
>> > with profiling/benchmarks. Otherwise it's too easy to fall into trap of
>> > optimizing wrong thing.
>>
>> Even with the USNO NOMAD catalog? That is a bit hard to believe,
>> although it might be the case. With the USNO NOMAD catalog, KStars
>> crawls when zoomed in on Sagittarius.
>
>
> I'm using NOMAD and I've attached some graphs from VTune. Note that they are
> all red, since we only ever use one core, of the four available on my
> machine.
>
> I tested them by running opening KStars and maximizing the number of
> displayed stars, and then slewing back and forth (with no hidden objects
> during slewing): http://i.imgur.com/BVxGi96.jpg
>
It looks like we are dominated by trigonometry calls here.