Hi Mark, On Tue, Sep 22, 2009 at 12:49:17AM +0100, Mark Burton wrote:

Reduce number of Table A entries.

Previously, Table A entries were unique for each combination of start node, end node and RoadDef. But no information from the start and end nodes goes into Table A so we can ignore the start and end nodes and all roads within a given routing centre that use the same RoadDef can now share a Table A entry. This reduces the number of entries required which makes the .img files smaller and, hopefully, also improves the routing because routing centres can now cover a larger area.

I have tested this with mapsource and on a Nuvi and it appears to work OK but it really needs more testing before it could be considered for committing.

I successfully tested it on Finland with Edge 705 firmware 2.90. The map is slightly smaller (36 megabytes instead of 37) and routing (car and bicycle, 200 to 250 km distance) still works. It still makes a stupid detour for the bicycle route, but I would blame that on the Garminware.

So, all feedback is welcome regarding the effect this patch has on routing performance. With the patch, the routing changed and I thought it was more sensible but perhaps that's just wishful thinking.

It could be that the bicycle route calculation was faster with this patch, but then again, there were not that many streets to choose from in my test. Calculation of bicycling routes through cities has always been slowest (multiple minutes). Marko

Reduce number of Table A entries. Previously, Table A entries were unique for each combination of start node, end node and RoadDef. But no information from the start and end nodes goes into Table A so we can ignore the start and end nodes and all roads within a given routing centre that use the same RoadDef can now share a Table A entry. This reduces the number of entries required which makes the .img files smaller and, hopefully, also improves the routing because routing centres can now cover a larger area. I have tested this with mapsource and on a Nuvi and it appears to work OK but it really needs more testing before it could be considered for committing. So, all feedback is welcome regarding the effect this patch has on routing performance. With the patch, the routing changed and I thought it was more sensible but perhaps that's just wishful thinking. My GB map shrunk from 180 to 174 Mb with this patch. The Nuvi calculated a route from Lands End to Thurso (800+ miles and quite a few tiles) in no more than 10 seconds. Cheers, Mark Hi Mark, Up to now I've just been following the discussions without any participation, since I am IT-challenged, and just barely understand. But now you touch a subject close to my heart. I MkGMap Southern Africa for my nuvi200W. Making Southern Africa in one tile I can route maximum approx 1400km.(870m) I can approve slightly by increasing --remove_short_arcs=50, but that distorts the map :( Making SA in 2 tiles routing capability reduces to approx. 700km (435m) roughly half? I would dearly love to try this patch, But I don't even have a slight clue how to apply a patch. Is there a simple tutorial available somewhere that is suitable for realy simple-minded non-techs? Or is there a way that someone can apply the patch and make it available for people like me (although I feel like the only non-tech around and in that case its propably too much trouble;( Anyway if someone would take the time to either explain (in very simple and precise terms) or apply the patch for me I would gladly test it. If not, then I will very impatiently wait for the changes to be comitted. Thanks for all the hard work you guys put into this project. I enjoy it tremenduously. Groete BennieD The opinions contained in this message are those of the sender only and do not reflect those of Sappi Limited or any of its subsidiary or associated companies. "This message, including any attachment(s), may contain information which is private, privileged or confidential and is intended solely for the use of the individual or entity named in this message. If you are not the intended recipient of this message, please notify the sender thereof and destroy/delete the message. Neither the sender nor Sappi Limited (including its subsidiaries and associated companies, jointly referred to as 'Sappi') shall incur any liability resulting directly or indirectly from accessing any of the attached files which may contain a virus or the like. Any opinions, statements, conclusions and other information contained in this message and/or its attachment(s) that do not relate or refer to the official business of Sappi Limited or any of its subsidiary or associated companies shall be regarded as neither provided nor approved by any Sappi company. Views expressed in this message or its attachment(s) may not necessarily be those of Sappi and Sappi cannot be held liable for any direct or indirect loss or injury resulting from the contents of a message and/or its attachments." Directors names A list of Sappi companies and the names of their directors can be retrieved from http://www.sappi.com/SappiWeb/Investor+info/Corporate+governance/Board+resum... ##################################################################################### Scanned by MailMarshal - Marshal's comprehensive email content security solution. Download a free evaluation of MailMarshal at www.marshal.com #####################################################################################

Mark, As far as I can see, it works well. I haven't tested it very thoroughly, but I don't find immediate oddities. There's still the various routing oddities. Mapsource sometimes doesn't find a route; my Nuvi sometimes finds weird routes (and sometimes does it right). Anyway, your patch makes the image file a bit smaller and does not seem to change routing (not better, not worse). Best regards, Valentijn Mark Burton schreef:

Reduce number of Table A entries. [...]