Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
Am Samstag, den 08.08.2009, 14:42 +0200 schrieb Martin Koppenhoefer: An example from the result of the current tidy-points-function here: http://trac.openstreetmap.org/attachment/ticket/2148/090808_potlatch_tidy-points_.png The exsample shows a problem which I also had once until I found that at least the simplify way plugin of JOSM has an option named simplify-way.max-error in the preference. Unfortunately, the default value of this option seems to be very high. If you set it to 1 (one meter) means below the accuracy of any currently available GPS than it should not be a problem. Problem for the JOSM plugin is that this option is not automatically added to the preferences and hidden in the description in the WIKI and you have to actively search for this option. Means the user has likely already done some damage before he is forced to change something. So I would think, that if the default value of the plugin is set to 1 and the option is automatically added to the preferences, than the situation would be much less bad and it would become a useful tool. Regards Andre signature.asc Description: Dies ist ein digital signierter Nachrichtenteil ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
Hi! Martin Koppenhoefer schrieb: 2009/8/9 Liz ed...@billiau.net: I concur I found about 350 -400 km of highway uploaded (twice) with points at one per second at 100kmh travel speed Once uploaded and made into a way, and then the way deleted without removing the points, then uploaded again and while we have editors that allow that sort of default behaviour, then we need simplifying tools not sure. If someone left a real mess (like here leaving thousands of useless nodes behind), maybe it's better to undo his action and start from scratch. Why? When applying simplify way on these you get exactly what you want. bye Nop ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
[OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
Hi! Andre Hinrichs schrieb: Problem for the JOSM plugin is that this option is not automatically added to the preferences and hidden in the description in the WIKI and you have to actively search for this option. +1 As long as you don't have any idea that such an option exists you don't start looking for it. So I would think, that if the default value of the plugin is set to 1 and the option is automatically added to the preferences, than the situation would be much less bad and it would become a useful tool. I disagree. Actually, when I download a plugin, I assume that the default operation of the plugin is already set to reasonable values and there should be no need to change anything before using it. If you set it to 1 it will simply appear broken. The main problem is simply that the tool looks harmless, but isn't, and is easily applied wrongly due to an overly aggressive default setting. Why don't we simply add a dialog when you apply the tool, showing the current setting, allowing to change it and giving some reasonable upper and lower bounds for the value. To prevent accidential damage, there could be a warning when you are using it in a dangerous or most likely harmful way. E.g. more than 10 ways are selected or using it on ways that already have less than 10 nodes. bye Nop ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
Hi! Apollinaris Schoell schrieb: To prevent accidential damage, there could be a warning when you are using it in a dangerous or most likely harmful way. E.g. more than 10 ways are selected or using it on ways that already have less than 10 nodes. use the plugin and if you miss features file a trac ticket. but you will see it's all builtin already How many users do you think are using JOSM? How many of those have any idea what trac is? I am not missing those features, I already did some damage simplyfying ways and learned from it. This is about future users. bye Nop ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
2009/8/10 Nop ekkeh...@gmx.de: Hi! Apollinaris Schoell schrieb: To prevent accidential damage, there could be a warning when you are using it in a dangerous or most likely harmful way. E.g. more than 10 ways are selected or using it on ways that already have less than 10 nodes. IMHO let not apply it to more than 1 way at a time will be an approach. If we agree that it is in every case necessary to manually control the effect of this function, why should you apply it to more than 1 way? I am not missing those features, I already did some damage simplyfying ways and learned from it. This is about future users. +1 and NOP is a poweruser. Imagine hundreds or thousands of users that don't want to follow the mailing-list and read the wiki twice a month but just do some occasional mapping. cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
On Aug 10, 2009, at 7:45 AM, Nop wrote: Hi! Apollinaris Schoell schrieb: To prevent accidential damage, there could be a warning when you are using it in a dangerous or most likely harmful way. E.g. more than 10 ways are selected or using it on ways that already have less than 10 nodes. use the plugin and if you miss features file a trac ticket. but you will see it's all builtin already How many users do you think are using JOSM? How many of those have any idea what trac is? I am not missing those features, I already did some damage simplyfying ways and learned from it. This is about future users. the warnings are builtin, don't understand how you can do big damage. the default for simplify is aggressive but everyone able to download a plugin will also watch the change when done the first time. I considered to file a ticket for the default value but didn't see a need. I don't think newbies use this function a lot but I might be completely wrong. bye Nop ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [Talk-de] [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
Hi! Andre Hinrichs schrieb: Problem for the JOSM plugin is that this option is not automatically added to the preferences and hidden in the description in the WIKI and you have to actively search for this option. +1 As long as you don't have any idea that such an option exists you don't start looking for it. So I would think, that if the default value of the plugin is set to 1 and the option is automatically added to the preferences, than the situation would be much less bad and it would become a useful tool. I disagree. Actually, when I download a plugin, I assume that the default operation of the plugin is already set to reasonable values and there should be no need to change anything before using it. If you set it to 1 it will simply appear broken. The main problem is simply that the tool looks harmless, but isn't, and is easily applied wrongly due to an overly aggressive default setting. Why don't we simply add a dialog when you apply the tool, showing the current setting, allowing to change it and giving some reasonable upper and lower bounds for the value. To prevent accidential damage, there could be a warning when you are using it in a dangerous or most likely harmful way. E.g. more than 10 ways are selected or using it on ways that already have less than 10 nodes. bye Nop ___ Talk-de mailing list Talk-de@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-de
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
Martin and I have had this conversation on private e-mail too, but one point bears repeating: I know that some people like this tidy-points-function to work on TIGER-Data, but I tell you: if the TIGER-Data is not good/precise, it won't get better using this function ;-) That is evidently not true. Find a grid system - almost any US city will do. Look at the TIGER data. It weaves and waves all over the place. Turn on the Yahoo imagery, align the start and end points of the way, and select the 'Tidy' function. Hey presto, the street is now correctly aligned to the grid. You could have done this manually, but it would have taken 10 times as long and wouldn't be as precise. _That_ is why this function is here: to simplify the work of one of the most tedious parts of TIGER fixup. As always, it's of no use for my mapping should not be extrapolated to it's of no use and should be banned. cheers Richard -- View this message in context: http://www.nabble.com/to-all-potlatch-and-JOSM-users---automatic-simplification-of-geometry-tp24877882p24885509.html Sent from the OpenStreetMap - General mailing list archive at Nabble.com. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
On Sun, 9 Aug 2009, Richard Fairhurst wrote: Turn on the Yahoo imagery, align the start and end points of the way, and select the 'Tidy' function. Hey presto, the street is now correctly aligned to the grid. You could have done this manually, but it would have taken 10 times as long and wouldn't be as precise. And then you realise that the alignment of Yahoo Imagery is wrong on most places, and you have killed good vector material. Great job :) Stefan ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
Stefan de Konink wrote: And then you realise that the alignment of Yahoo Imagery is wrong on most places, and you have killed good vector material. Great job :) Good vector material? Tell me, have you ever _seen_ TIGER? Seriously, you're kidding me. Yahoo may be out-of-alignment here and there but by and large if the street looks straight in Yahoo, it is straight. And US city streets generally are. TIGER streets are bonkers mad wavy. I can't believe I'm having to explain this to people who could actually go and see for themselves with two clicks of the mouse. Ah, the joys of mailing lists. :( cheers Richard ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
Richard Fairhurst wrote: _That_ is why this function is here: to simplify the work of one of the most tedious parts of TIGER fixup. As always, it's of no use for my mapping should not be extrapolated to it's of no use and should be banned. But maybe in those parts of the world where streets are not perfectly straight, it is of no use and even dangerous in the hands of newbies should be extrapolated to it should not be included by default but provided by a plugin/option? Tobias Knerr ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
On Sun, 9 Aug 2009, Richard Fairhurst wrote: Stefan de Konink wrote: And then you realise that the alignment of Yahoo Imagery is wrong on most places, and you have killed good vector material. Great job :) Good vector material? Tell me, have you ever _seen_ TIGER? Yes, and I have also _seen_ Yahoo been wrong on more places than it was right. So I am still skeptical people tracing Yahoo and claiming they are better than [insert source here] mainly because except that source they have 0 ground reference. Seriously, you're kidding me. Yahoo may be out-of-alignment here and there but by and large if the street looks straight in Yahoo, it is straight. And US city streets generally are. TIGER streets are bonkers mad wavy. Most likely this is true because the TIGER dataset was actually traced from/for a much lower precision map, hence wavy because you are plotting it on a far higher resolution then it was created for. With respect to TIGER you might say: TIGER is *so* bad, Yahoo will always be better. My point is, unless Yahoo is actualy validated where you are tracing it gives poor output too, no matter how bad you think TIGER is. Stefan ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
Tobias Knerr wrote: But maybe in those parts of the world where streets are not perfectly straight, it is of no use and even dangerous in the hands of newbies should be extrapolated to it should not be included by default but provided by a plugin/option? Hm. I can think of plenty of towns where one part of town has grid- like streets, another a few metres away is all curly housing estate roads. As I've said several times to Martin, once I have a spare minute I'll add some sort of confirmation dialogue if you try to straighten a street with more than n metres divergence. But for now, I'm off on holiday. cheers Richard ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
On Sun, Aug 9, 2009 at 11:12 AM, Stefan de Koninkste...@konink.de wrote: On Sun, 9 Aug 2009, Richard Fairhurst wrote: Stefan de Konink wrote: And then you realise that the alignment of Yahoo Imagery is wrong on most places, and you have killed good vector material. Great job :) Good vector material? Tell me, have you ever _seen_ TIGER? Yes, and I have also _seen_ Yahoo been wrong on more places than it was right. So I am still skeptical people tracing Yahoo and claiming they are better than [insert source here] mainly because except that source they have 0 ground reference. Seriously, you're kidding me. Yahoo may be out-of-alignment here and there but by and large if the street looks straight in Yahoo, it is straight. And US city streets generally are. TIGER streets are bonkers mad wavy. Most likely this is true because the TIGER dataset was actually traced from/for a much lower precision map, hence wavy because you are plotting it on a far higher resolution then it was created for. With respect to TIGER you might say: TIGER is *so* bad, Yahoo will always be better. My point is, unless Yahoo is actualy validated where you are tracing it gives poor output too, no matter how bad you think TIGER is. Um, no. It'll be potentially misaligned, potentially outdated, and potentially misinterpreted. So potentially poor, but it's entirely possible (and actually quite likely) that it's fine and you get pretty good data out. And it's definitely better than most tiger data I've ever seen. So choosing between potentially poor, and very horrible isn't really so hard is it. Hopefully someone on the ground will eventually verify it -- they can fix it if it's still broken. Dave ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
--- On Sun, 9/8/09, Stefan de Konink ste...@konink.de wrote: Most likely this is true because the TIGER dataset was actually traced from/for a much lower precision map, hence wavy because you are plotting it on a far higher resolution then it was created for. With respect to TIGER you might say: TIGER is *so* bad, Yahoo will always be better. My point is, unless Yahoo is actualy validated where you are tracing it gives poor output too, no matter how bad you think TIGER is. Assuming that yahoo is wrong, at least it will be consistently wrong and it's trivially to mass move ways when you do get reference points to re-align the data to. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
On Sun, 9 Aug 2009, John Smith wrote: Assuming that yahoo is wrong, at least it will be consistently wrong and it's trivially to mass move ways when you do get reference points to re-align the data to. Moving stuff in GIS is never trivial. You don't know why it is wrong, and even if it looks 'locally' shifted it could be even misrectified causing it to be shifted and streched possibly rotated. My own town is in this situation. And most AND data imported in NL has also a very strange offset to what several GPX traces show as 'this is the road'. Stefan ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
On Sun, 9 Aug 2009, Shaun McDonald wrote: How does your town compare to Yahoo? It seems to have an offset in both X and Y. But I can only see that locally. I don't know if there is a more global problem. I have only heard of trival shifts in the rectification being a problem. I think it could be fixed to just measure some points in on the ground and hook them up to a pixel then transform it. Maybe we could work /with/ Yahoo on this. Stefan ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
Am Samstag 08 August 2009 14:42:43 schrieb Martin Koppenhoefer: An example from the result of the current tidy-points-function here: http://trac.openstreetmap.org/attachment/ticket/2148/090808_potlatch_tidy-p oints_.png In this case it looks more like an error of the tidy-function, or at least it having wrong parameters. Most of the nodes in the back of the linkway are indeed collinear and can probably be removed without loss of precision. Personally, I almost never use this function. There were a few cases where someone seems to have converted a GPX track, or where it was clear that the excessive amount of nodes was wrong, because I knew the concerning area. Regards, Marc signature.asc Description: This is a digitally signed message part. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
--- On Sun, 9/8/09, Stefan de Konink ste...@konink.de wrote: Moving stuff in GIS is never trivial. You don't know why it is wrong, and even if it looks 'locally' shifted it could be even misrectified causing it to be shifted and streched possibly rotated. You get 4 or more points on the ground by GPS and you align to that, I meant suburb level, not an entire city or states or countries. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
2009/8/9 Richard Fairhurst rich...@systemed.net: As I've said several times to Martin, once I have a spare minute I'll add some sort of confirmation dialogue if you try to straighten a street with more than n metres divergence. But for now, I'm off on holiday. Actually those confirmation dialogues are a bit annoying (if I imagine someone cleaning big aeras of TIGER-data), but what about a keyboard shortcut (preferably with modifier like shift or ctrl) instead of an Icon? For mappers aware of what they are doing it's completely OK to use this functions in a responsible manner. Actually I wasn't aware myself that it just straightens (thought it would simplify, blame on me). Maybe there could be added the word straighten to the function name tidy points in some way. In my area (and probably not only here) there's lots of registrees that actually haven't performed a single edit, and other's that think potlatch is an online painting programm (drawing motorways wildly across the city-center) when you write to them, they apologize and say they didn't know they were actually modifying the public database, so my concern is more about people incidently harming data, not about real vandalism. anyway: have a nice holiday! cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
2009/8/9 John Smith delta_foxt...@yahoo.com: Assuming that yahoo is wrong, at least it will be consistently wrong and it's trivially to mass move ways when you do get reference points to re-align the data to. no, unfortunately according to my gps-traces and knowledge of the actual situation in my city, it is sometimes misaligned and distorted, sometimes it seems OK. There is no general rule about this (seems to depend on rectifiying and stiching of the original fotos / on their tiling). There is also often a curvy distortion, where perfectly straight buildings and streets are curved in yahoo. cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
On Sun, 9 Aug 2009, John Smith wrote: You get 4 or more points on the ground by GPS and you align to that, I meant suburb level, not an entire city or states or countries. Already saw an OSM editor supporting realigning Yahoo Imagery based on existing points? Stefan ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
--- On Sun, 9/8/09, Stefan de Konink ste...@konink.de wrote: Already saw an OSM editor supporting realigning Yahoo Imagery based on existing points? Not automatically, but JOSM can shift the yahoo image to align it to known points then you just move nodes/ways as needed. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
Hi! Martin Koppenhoefer schrieb: I want to point attention to the potlatch-funtion tidy-points (similar to JOSM simplify way). I encourage everybody not to use these functions (at least not on data someone else entered) as it harms severly the data. First of all, I agree with you that these function can seriously harm data, at least when carelessly applied to data that is already well-designed. Some people mentioned that the default settings of these tools are very agressive - this is true and a more lenient approach might produce much better results. But then, I have not seen any options to change this (in JOSM). But on the other hand, there's some areas where you need those tools. During my mapping I have found two areas where the way were hideously over-defined. When ways have 10 or 20 times more nodes than required to show their none-too-complex form or when nodes are set in 2m distances it appears that someone has just uploaded raw GPS traces. This makes those areas nearly unusable as even a very modest bounding box will exeed the 50k nodes limit. In these cases, simplify way is your good friend. Eventually, in an anarchic open source society like OSM you can't take away a tool anyway, so don't even try. But it is definitely worth refining and pointing out proper and improper uses. bye Nop ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
Some people mentioned that the default settings of these tools are very agressive - this is true and a more lenient approach might produce much better results. But then, I have not seen any options to change this (in JOSM). I think you can change the presets in Einstein-mode. cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
2009/8/9 John Smith delta_foxt...@yahoo.com: --- On Sun, 9/8/09, Stefan de Konink ste...@konink.de wrote: Already saw an OSM editor supporting realigning Yahoo Imagery based on existing points? Not automatically, but JOSM can shift the yahoo image to align it to known points then you just move nodes/ways as needed. AFAIK potlatch can do this as well, it is much better than nothing but it doesn't do a full job if the image needs warping (instead of moving). Without the original imagery you will also get worse results because yahoo already manipulated the images, now you do it again, in the end the details that normally could have been on the limit of visibility will disappear. cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
2009/8/9 Liz ed...@billiau.net: I concur I found about 350 -400 km of highway uploaded (twice) with points at one per second at 100kmh travel speed Once uploaded and made into a way, and then the way deleted without removing the points, then uploaded again and while we have editors that allow that sort of default behaviour, then we need simplifying tools not sure. If someone left a real mess (like here leaving thousands of useless nodes behind), maybe it's better to undo his action and start from scratch. cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
On Aug 9, 2009, at 2:23 PM, Liz wrote: On Mon, 10 Aug 2009, Nop wrote: Some people mentioned that the default settings of these tools are very agressive - this is true and a more lenient approach might produce much better results. But then, I have not seen any options to change this (in JOSM). It was in advanced preferences. Can't find it right now simplify-way.max-error you need to play a bit with the numbers to find the right one for your use model But on the other hand, there's some areas where you need those tools. During my mapping I have found two areas where the way were hideously over-defined. When ways have 10 or 20 times more nodes than required to show their none-too-complex form or when nodes are set in 2m distances it appears that someone has just uploaded raw GPS traces. This makes those areas nearly unusable as even a very modest bounding box will exeed the 50k nodes limit. In these cases, simplify way is your good friend. I concur I found about 350 -400 km of highway uploaded (twice) with points at one per second at 100kmh travel speed Once uploaded and made into a way, and then the way deleted without removing the points, then uploaded again and while we have editors that allow that sort of default behaviour, then we need simplifying tools +1 this discussion is pointless. all editors allow deleting ways. why should we bother about the power of simplifying a way. Eventually, in an anarchic open source society like OSM you can't take away a tool anyway, so don't even try. But it is definitely worth refining and pointing out proper and improper uses. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
[OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
Hi all, I want to point attention to the potlatch-funtion tidy-points (similar to JOSM simplify way). I encourage everybody not to use these functions (at least not on data someone else entered) as it harms severly the data. IMHO OSM is a project about drawing a collaborative map, not about computers drawing it. They don't know the world, e.g. don't know and can't know, where there is a curve and where the street is straight. For this reason, they will never be able to do the job of generalization as good as humans can do. Therefore it is not just about optimizing the algorithm of performing this action, but it is generally not possible for computers to do it. Of course an elaborated algorithm (that knows for example the functions usually used to design curves in streets, ramps, minimum radius, etc., probably even considerating the road class and speedlimits) could do a much better job than the current one, but it will still be guessing and not knowing about the optimal geometry. I think that the respect for the work of the comunity requests us to ban these functions or restrict the use to ways drawn but not yet uploaded. An example from the result of the current tidy-points-function here: http://trac.openstreetmap.org/attachment/ticket/2148/090808_potlatch_tidy-points_.png I'd like to start a discussion about which automated functionalities we want to allow and if there is a majority in the community for setting some limits to what should be possible by automated interaction. What if I scripted my own tidy-up-function that allows to specify a location, radius and tag and then deletes all these tags inside the radius. Might be useful in areas to start certain things from scratch where data is not reliable (I'm obviously not serious, that's probably an extreme example, but there might be other functions that in some cases are useful, in others they aren't). I know that some people like this tidy-points-function to work on TIGER-Data, but I tell you: if the TIGER-Data is not good/precise, it won't get better using this function ;-) cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
On Sat, Aug 8, 2009 at 10:42 PM, Martin Koppenhoeferdieterdre...@gmail.com wrote: I'd like to start a discussion about which automated functionalities we want to allow As long as the automated functionalities are initiated and controlled by human judgment, there is no need to limit them. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
On Sat, 8 Aug 2009 14:42:43 +0200, Martin Koppenhoefer dieterdre...@gmail.com wrote: Hi all, I want to point attention to the potlatch-funtion tidy-points (similar to JOSM simplify way). I encourage everybody not to use these functions (at least not on data someone else entered) as it harms severly the data. IMHO OSM is a project about drawing a collaborative map, not about computers drawing it. They don't know the world, e.g. don't know and can't know, where there is a curve and where the street is straight. But what is a straight line? I have seen different results of straight line depending on projection and on line calculation. For example, UTM Straightline, Great Circle and Rhumb Line makes different straight lines, and they look different on UTM, WGS84, ED50 or other projections. The computerised organization, does it make a straight UTM straight line or a straight Rhumb Line? (I guess they do not try Great Circle) And does it calculate to some certain predefined datum, or the active datum in your JOSM preferences? -- Brgds Aun Johnsen via Webmail ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] to all potlatch and JOSM users - automatic simplification of geometry
I know that some people like this tidy-points-function to work on TIGER-Data, but I tell you: if the TIGER-Data is not good/precise, it won't get better using this function ;-) bad data doesn't get worse either. for a lot of tiger data it can compact without any loss. And tiger is not a community created data. anyone improving it shouldn't be limited As long as someone verifies the results it's same like any other user input. Josm default is too aggressive tough. this should be definitely changed. cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
