I have created another virtual solar system model a good decade ago and modeled a comet consisting of an irregular (.OBJ ?) core, coma (simple 2D billboard) and two parabolas textured with a semitransparent gradient that dissipated on the outer end. The parabolas became visible somewhere outside Mars orbit and grew in solar vicinity, a bluish slim "gas" tail pointed strictly away from the sun, a wider whitish "dust" tail lagged somewhat behind the comet depending on its speed. It did not look too bad from a distance even with static textures (I still had rather fresh memories of Hyakutake and Hale-Bopp), but maybe the gradient can even be (slowly!) animated nowadays! Of course, the comet data must include some information about "absolute magnitude", there are standardized parameters in comet elements for this, hopefully they are also included with orbital elements updates? This would at least be a reasonable start. But no, I don't think I have the code anymore, sorry.
Kind regards, Georg On Mo, 19.03.2012, 23:38, Reaves, Timothy wrote: > If you feel you can take on the comet rendering, please do. The second > one > you mention is fine as well. It comes down to your abilities with OpenGL, > and then the modeling of either phenomena. > > On Mon, Mar 19, 2012 at 6:35 PM, Srijan Tiwari > <[email protected]>wrote: > >> comet rendering appears too difficult then, thanks for the advice >> what about "satellite and ring shadows on parent planets"? >> >> Regards >> >> On 20 March 2012 03:56, Barry Gerdes <[email protected]> wrote: >> >>> The subject of comet rendering is another wishlist item that has been >>> brought up many times in the past and usually consigned to the "too >>> Hard" >>> basket >>> Providing a meaning full 3D display would be an immense task due to the >>> nature of comets and their changing form as they approach the Sun. >>> However a 2D texture simulation could probably be implimented that >>> could >>> have an intensity graded tail that can show depending on visible >>> brightness >>> and oriented depending on its location relative to the sun along with >>> its >>> relative size. >>> >>> >>> Barry Gerdes >>> Beaumont Hills Observatory >>> S 33' 41' 44" E 150' 56' 32" >>> >>> >>> ------------------------------ >>> Date: Tue, 20 Mar 2012 03:37:50 +0530 >>> From: [email protected] >>> To: [email protected] >>> Subject: [Stellarium-pubdevel] GSoc Project "Realistic comet rendering" >>> >>> >>> dear sir or madam, >>> I am a student of IIIT Hyderabad , India. Due to my inclination towards >>> opengl and computer graphics i was really interested in projects >>> offered by Stellarium, especially "Realistic comet renderin". >>> I have worked out many projects in opengl including 2-D and 3-D games >>> with lighting and shading effects, and have also done Computer graphics >>> course thus very well understand the pipeline and the mathematics >>> involved in graphics. >>> Please provide me some guidelines how should i work towards this >>> project. >>> What are your expectations from the project? >>> Are you expecting some specific bugs to be solved? Or anything >>> significant related to the project. >>> Can i have some source code for reference ? >>> >>> Regards >>> Srijan >>> >>> >>> ------------------------------------------------------------------------------ >>> This SF email is sponsosred by: Try Windows Azure free for 90 days >>> Click >>> Here http://p.sf.net/sfu/sfd2d-msazure >>> _______________________________________________ Stellarium-pubdevel >>> mailing list [email protected] >>> https://lists.sourceforge.net/lists/listinfo/stellarium-pubdevel >>> >>> >>> -- DI Dr Georg Zotti Archaeoastronomy / ASTROSIM VIAS-Vienna Institute for Archaeological Science University of Vienna ------------------------------------------------------------------------------ This SF email is sponsosred by: Try Windows Azure free for 90 days Click Here http://p.sf.net/sfu/sfd2d-msazure _______________________________________________ Stellarium-pubdevel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/stellarium-pubdevel
