On 9/10/07, Stefan Steiniger <[EMAIL PROTECTED]> wrote: > > > Paul Austin schrieb: > > CoordinateOperations should use the Ellipsoid they are created with (can > > be parameterised), they should not need to know how to do Ellipsoid > > transformations. Ellipsoid transformations would only need to be defined > > once in geographics to/from one ellipsoid to another, or we could define > > a pivot ellipsoid then you'd only need to go to/from that ellipsoid. > > > > They one thing we need to be careful of is the accuracy of the > > transformations, which may mean avoiding too many transformation steps. > > mhm.. > actually if i remember x,y => lat/lon and vice versa are approximating > calculations (Taylor expansions?).. so some insecure is always axisting
Actually, I'm not sure this is true. For example, the Gnomonic projection I am working on uses simple trig, and no other appriximations that I know of. (Thus its beauty for small areas.) Unless you count the approximation used in calculating the trig ratios. SS > so.. i am leaving the thread for today > > stefan > > > Paul > > > > ------------------------------------------------------------------------- > > This SF.net email is sponsored by: Microsoft > > Defy all challenges. Microsoft(R) Visual Studio 2005. > > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > > _______________________________________________ > > Jump-pilot-devel mailing list > > Jump-pilot-devel@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel > > > > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2005. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > Jump-pilot-devel mailing list > Jump-pilot-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel > ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Jump-pilot-devel mailing list Jump-pilot-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel
