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#271681 - 09/12/2005 00:25 navigation revisited
Daria carpal tunnel Registered: 24/01/2002 Posts: 3937 Loc: Providence, RI	Try out RoadNav (http://roadnav.sourceforge.net/). The navigation functionality is in a library released under the LGPL.
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#271682 - 09/12/2005 13:27 Re: navigation revisited [Re: Daria]
wfaulk carpal tunnel Registered: 25/12/2000 Posts: 16706 Loc: Raleigh, NC US	Quote: Roadnav uses the free TIGER/Line files from the US Census Bureau to build the maps Which we've determined doesn't have accurate enough data, missing things like one-way roads. _________________________ Bitt Faulk
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#271683 - 09/12/2005 15:32 Re: navigation revisited [Re: Daria]
siberia37 old hand Registered: 09/01/2002 Posts: 702 Loc: Tacoma,WA	Quote: Try out RoadNav (http://roadnav.sourceforge.net/). The navigation functionality is in a library released under the LGPL. Looks pretty sweet- have to check that one out. It will take some code examination to see if it's up to the challenge of running on the Empeg (with no Math Coprocessor!). And of course, Navigation will never be great with TIGER but I think we can always do our point-to-point directions with Google maps and be happy.
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#271684 - 09/12/2005 16:11 Re: navigation revisited [Re: wfaulk]
tfabris carpal tunnel Registered: 20/12/1999 Posts: 31565 Loc: Seattle, WA	I seem to recall they said they also used a second data source in addtiion to Tiger. Perhaps it's worth a look. _________________________ Tony Fabris
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#271685 - 09/12/2005 21:31 Re: navigation revisited [Re: siberia37]
siberia37 old hand Registered: 09/01/2002 Posts: 702 Loc: Tacoma,WA	Quote: Quote: Try out RoadNav (http://roadnav.sourceforge.net/). The navigation functionality is in a library released under the LGPL. Looks pretty sweet- have to check that one out. It will take some code examination to see if it's up to the challenge of running on the Empeg (with no Math Coprocessor!). And of course, Navigation will never be great with TIGER but I think we can always do our point-to-point directions with Google maps and be happy. An examination of the code reveals lots of floating point operations- it's main base point unit seems to be represented by a double. This is opposed to RoadMap where the main base unit is an Integer- Roadmap isn't exactly quick, so I can't Imagine RoadNav would be doable on the Empeg. At least not without some code changes..
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#271686 - 09/12/2005 21:37 Re: navigation revisited [Re: siberia37]
tfabris carpal tunnel Registered: 20/12/1999 Posts: 31565 Loc: Seattle, WA	Aren't there a whole lot of FP-to-Integer libraries that could be grafted in? I mean, yes, I know those aren't as fast as an FPU, but how much FP math are we talking about? _________________________ Tony Fabris
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#271687 - 09/12/2005 23:51 Re: navigation revisited [Re: tfabris]
tman carpal tunnel Registered: 24/12/2001 Posts: 5528	Quote: Aren't there a whole lot of FP-to-Integer libraries that could be grafted in? I mean, yes, I know those aren't as fast as an FPU, but how much FP math are we talking about? You can either let the kernel emulate the FP instructions or link in a library which handles it for you. Either one isn't going to be as fast as if you used integers in the first place.
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#271688 - 08/01/2006 04:26 Re: navigation revisited [Re: tfabris]
genixia Carpal Tunnel Registered: 08/02/2002 Posts: 3411	User-space FP emulation is doable - I've even done in-kernel FP emulation on the empeg. You'd take the performance hit though if you're doing a lot of FP operations. I suspect that would be the case here. _________________________ Mk2a 60GB Blue. Serial 030102962 sig.mp3: File Format not Valid.
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#271689 - 08/01/2006 13:10 Re: navigation revisited [Re: tfabris]
mlord carpal tunnel Registered: 29/08/2000 Posts: 14477 Loc: Canada	The default Empeg and Hijack kernels already include floating-point support, emulated in software. -ml
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#271690 - 08/01/2006 15:28 Re: navigation revisited [Re: mlord]
tfabris carpal tunnel Registered: 20/12/1999 Posts: 31565 Loc: Seattle, WA	So Derrick, how much FP are we talking about in that code? _________________________ Tony Fabris
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#271691 - 09/01/2006 13:53 Re: navigation revisited [Re: tfabris]
wfaulk carpal tunnel Registered: 25/12/2000 Posts: 16706 Loc: Raleigh, NC US	If the main unit is a floating point figure, as stated, I'd guess nearly all of them. _________________________ Bitt Faulk
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