Re: [Qgis-developer] Labels on topologically wrong polygons
On Jul 25, 2013, at 12:18 AM, Paolo Cavallini wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Il 25/07/2013 01:57, William Kyngesburye ha scritto: If liblwgeom becomes a requirement for QGIS, I'll certainly be packaging it with QGIS, and adding instructions to INSTALL. it is not a requirement, but it wouold be good if you could include it anyway, to let osx users enjoy our plugin. Is it a compiled plugin? Wouldn't that have to be included in the QGIS source, thus making a liblwgeom requirement? Or are you using ctypes to access liblwgeom functions from python? It probably requires a full install of Postgres. it should not; at least, o win and deb this is not the case. I mean configuration probably requires postgres. Compilation of only liblwgeom after configuration does not. - William Kyngesburye kyngchaos*at*kyngchaos*dot*com http://www.kyngchaos.com/ Oh, look, I seem to have fallen down a deep, dark hole. Now what does that remind me of? Ah, yes - life. - Marvin ___ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-developer
Re: [Qgis-developer] Labels on topologically wrong polygons
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Il 25/07/2013 15:20, William Kyngesburye ha scritto: Is it a compiled plugin? Wouldn't that have to be included in the QGIS source, thus making a liblwgeom requirement? Or are you using ctypes to access liblwgeom functions from python? It's a Python one. lwgeom is not a requirement, but it would be good to include it anyway; probably more and more of its functions will be used (easy to add them to the plugin). All the best. - -- Paolo Cavallini - Faunalia www.faunalia.eu Full contact details at www.faunalia.eu/pc Nuovi corsi QGIS e PostGIS: http://www.faunalia.it/calendario -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Icedove - http://www.enigmail.net/ iEYEARECAAYFAlHxJv8ACgkQ/NedwLUzIr4kawCeNYLK95OcwgFKzkNK1+GCiF99 s74AnRewHwjfZ1cVMZPnq0wFvd6zbaeq =+Ny2 -END PGP SIGNATURE- ___ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-developer
Re: [Qgis-developer] Labels on topologically wrong polygons
On Jul 25, 2013, at 8:24 AM, Paolo Cavallini wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Il 25/07/2013 15:20, William Kyngesburye ha scritto: Is it a compiled plugin? Wouldn't that have to be included in the QGIS source, thus making a liblwgeom requirement? Or are you using ctypes to access liblwgeom functions from python? It's a Python one. lwgeom is not a requirement, but it would be good to include it anyway; probably more and more of its functions will be used (easy to add them to the plugin). Hmm, unless QGIS itself starts using lwgeom, I don't think bundling tools for use by 3rd party plugins is the way to go. Maybe OK since it's an extension of Sextante (just refreshed what you said on this thread). Or could the plugin just be added to core Sextante? I'll think about options. - William Kyngesburye kyngchaos*at*kyngchaos*dot*com http://www.kyngchaos.com/ History is an illusion caused by the passage of time, and time is an illusion caused by the passage of history. - Hitchhiker's Guide to the Galaxy ___ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-developer
Re: [Qgis-developer] Labels on topologically wrong polygons
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Il 25/07/2013 15:38, William Kyngesburye ha scritto: Hmm, unless QGIS itself starts using lwgeom, I don't think bundling tools for use by 3rd party plugins is the way to go. Maybe OK since it's an extension of Sextante (just refreshed what you said on this thread). Or could the plugin just be added to core Sextante? that's the plan; of course it is only feasible if lwgeom is available for all major OS, so it's a chicken-egg problem. All the best. - -- Paolo Cavallini - Faunalia www.faunalia.eu Full contact details at www.faunalia.eu/pc Nuovi corsi QGIS e PostGIS: http://www.faunalia.it/calendario -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Icedove - http://www.enigmail.net/ iEYEARECAAYFAlHxK0wACgkQ/NedwLUzIr7gGgCfSWQTRbSRQRkO6uSRfoY20f3H fUUAn10M2aKPkcCSEnaYjxw4dFArG4iq =i40Z -END PGP SIGNATURE- ___ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-developer
[Qgis-developer] Labels on topologically wrong polygons
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi all. I noticed that labels are not placed on topologically wrong polygons. This makes sense, but is surprising for the user: could we think of some solution? All the best. - -- Paolo Cavallini - Faunalia www.faunalia.eu Full contact details at www.faunalia.eu/pc Nuovi corsi QGIS e PostGIS: http://www.faunalia.it/calendario -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Icedove - http://www.enigmail.net/ iEYEARECAAYFAlHv7bwACgkQ/NedwLUzIr4D1ACeKZdyAOUz7SAujvNy5ziztHTq RM8An05nyhyTMsJlts2GamUi2akvpCPy =hesG -END PGP SIGNATURE- ___ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-developer
Re: [Qgis-developer] Labels on topologically wrong polygons
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Il 24/07/2013 17:55, Larry Shaffer ha scritto: I think QGIS should offer the option to on-the-fly try to fix those geometries. This was discussed previously [0], and I think the best solution presented so far is to find a way to incorporate the standalone PostGIS library 'lwgeom' into the QGIS done for now: http://plugins.qgis.org/plugins/sextantelwgeomprovider/ Ideally, if someone where to find a way (maybe it is simple, but not for me) to have the lwgeom library compile-able as a standalone library, apart from PostGIS, it would we are doing it now, for osgeo4w. ready on debian. All the best. - -- Paolo Cavallini - Faunalia www.faunalia.eu Full contact details at www.faunalia.eu/pc Nuovi corsi QGIS e PostGIS: http://www.faunalia.it/calendario -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Icedove - http://www.enigmail.net/ iEYEARECAAYFAlHv+nUACgkQ/NedwLUzIr6orACgrj5T0/FytPBmOsiJTKfLzX/D NCUAoIY5yXtEt2Ddtht7nSnt7dq01Qi6 =2m/z -END PGP SIGNATURE- ___ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-developer
Re: [Qgis-developer] Labels on topologically wrong polygons
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Il 24/07/2013 18:21, Larry Shaffer ha scritto: But that just wraps the C++ library with Python doesn't? (Very nice, btw!) That still requires a full install of PostGIS/PostgreSQL (at this time): not, we have compiled it as standalone; in deb it is the same: http://packages.debian.org/sid/liblwgeom-2.0.3 For labeling, I don't think we would want to introduce Python into the mix, or require PostGIS to be installed. So, either C++ compiled-in or shared lib support would be best (for the speed). agreed Do you have some links to any notes on how this was done using the PostGIS source code? I'd like to make that library available for the Mac builds and pass the notes along to others. coming soon thanks. - -- Paolo Cavallini - Faunalia www.faunalia.eu Full contact details at www.faunalia.eu/pc Nuovi corsi QGIS e PostGIS: http://www.faunalia.it/calendario -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Icedove - http://www.enigmail.net/ iEYEARECAAYFAlHv//sACgkQ/NedwLUzIr4Y9wCfZm9hqdp2EcnBVShAbleg0DpW tMYAnR6S/thBQW/9XfWQekRZPAF2wYNZ =BSK3 -END PGP SIGNATURE- ___ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-developer
Re: [Qgis-developer] Labels on topologically wrong polygons
On 24/07/2013 17:55, Larry Shaffer wrote: I think QGIS should offer the option to on-the-fly try to fix those geometries. This was discussed previously [0] The MakeValid is not a fast process. Try to apply it on-the-fly will slow again the labelling flow. Another problem is tht it could change little , but not less important, part of a geometry. so if the user will decide to edit it . Instead of editing the original geometry it will edit a changed geometry. And save in the shapefile (o r other container) another more changed geometry. Don't forgot that the original ST_MakeValid of postgis (and also spatialite) will return also the removed parts of original geometry. (point , arc or other it was) To not lost of view the original geometry. ___ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-developer
Re: [Qgis-developer] Labels on topologically wrong polygons
Hi, On Wed, Jul 24, 2013 at 11:04 AM, aperi2007 aperi2...@gmail.com wrote: On 24/07/2013 17:55, Larry Shaffer wrote: I think QGIS should offer the option to on-the-fly try to fix those geometries. This was discussed previously [0] The MakeValid is not a fast process. Try to apply it on-the-fly will slow again the labelling flow. Yes, but only for those features that are tested to be invalid (already done). Also, as I noted, this should be optional, and probably disabled by default. Another problem is tht it could change little , but not less important, part of a geometry. so if the user will decide to edit it . Instead of editing the original geometry it will edit a changed geometry. And save in the shapefile (o r other container) another more changed geometry. The labeling engine sends to the backend PAL library *copies* of the feature geometries. So, the original geometry is never edited, i.e. the copy would be what is run through ST_MakeValid. Once the labels are created, those copied geometries are dumped and never rendered on the canvas. There should probably be some logging somewhere, if the geometry is invalid, but usually the copied geometry has been clipped to the extent rectangle. In other words, invalid geometries of the copies at that point have nothing to do with the original features, which may be valid. So, logging invalids at that point doesn't make sense. Don't forgot that the original ST_MakeValid of postgis (and also spatialite) will return also the removed parts of original geometry. (point , arc or other it was) This could be an issue, where a multi-geometry is return for a single input. It seems this could be overcome with some checks, and eventually fallback to rejecting the geometry, if necessary. To not lost of view the original geometry. Sorry. I don't understand your meaning here. Regards, Larry __**_ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/**mailman/listinfo/qgis-**developerhttp://lists.osgeo.org/mailman/listinfo/qgis-developer ___ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-developer
Re: [Qgis-developer] Labels on topologically wrong polygons
Hi Paolo, On Wed, Jul 24, 2013 at 10:25 AM, Paolo Cavallini cavall...@faunalia.itwrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Il 24/07/2013 18:21, Larry Shaffer ha scritto: But that just wraps the C++ library with Python doesn't? (Very nice, btw!) That still requires a full install of PostGIS/PostgreSQL (at this time): not, we have compiled it as standalone; in deb it is the same: http://packages.debian.org/sid/liblwgeom-2.0.3 For labeling, I don't think we would want to introduce Python into the mix, or require PostGIS to be installed. So, either C++ compiled-in or shared lib support would be best (for the speed). agreed Do you have some links to any notes on how this was done using the PostGIS source code? I'd like to make that library available for the Mac builds and pass the notes along to others. coming soon Actually, I hadn't tested building the standalone Mac liblwgeom.dylib since PostGIS 2.0.3 came out. I was able to easily build the .dylib for both 2.0.3 and with current source trunk. Trunk appears to now require the json-c lib, which was not part of the Kyngchaos framework installs, but is readily available via homebrew. So, it fairly simple to compile and include liblwgeom-2.0.3.dylib (422 KB) with Mac bundled app builds, once it is utilized directly in QGIS code. Very nice, indeed, for geometry repairing routines! William, here is what I did [0]. Please let me know if there is something I am missing in the build steps that might cause issues for use in a bundled QGIS. Thanks. [0] http://drive.dakotacarto.com/qgis/liblwgeom.dylib-build.txt Regards, Larry thanks. - -- Paolo Cavallini - Faunalia www.faunalia.eu Full contact details at www.faunalia.eu/pc Nuovi corsi QGIS e PostGIS: http://www.faunalia.it/calendario -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Icedove - http://www.enigmail.net/ iEYEARECAAYFAlHv//sACgkQ/NedwLUzIr4Y9wCfZm9hqdp2EcnBVShAbleg0DpW tMYAnR6S/thBQW/9XfWQekRZPAF2wYNZ =BSK3 -END PGP SIGNATURE- ___ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-developer
Re: [Qgis-developer] Labels on topologically wrong polygons
2013/7/24 Larry Shaffer lar...@dakotacarto.com Hi, On Wed, Jul 24, 2013 at 11:04 AM, aperi2007 aperi2...@gmail.com wrote: On 24/07/2013 17:55, Larry Shaffer wrote: I think QGIS should offer the option to on-the-fly try to fix those geometries. This was discussed previously [0] The MakeValid is not a fast process. Try to apply it on-the-fly will slow again the labelling flow. Yes, but only for those features that are tested to be invalid (already done). Also, as I noted, this should be optional, and probably disabled by default. Agree. Another problem is tht it could change little , but not less important, part of a geometry. so if the user will decide to edit it . Instead of editing the original geometry it will edit a changed geometry. And save in the shapefile (o r other container) another more changed geometry. The labeling engine sends to the backend PAL library *copies* of the feature geometries. So, the original geometry is never edited, i.e. the copy would be what is run through ST_MakeValid. Once the labels are created, those copied geometries are dumped and never rendered on the canvas. There should probably be some logging somewhere, if the geometry is invalid, but usually the copied geometry has been clipped to the extent rectangle. In other words, invalid geometries of the copies at that point have nothing to do with the original features, which may be valid. So, logging invalids at that point doesn't make sense. ok, your idea is more sophisticated. Don't forgot that the original ST_MakeValid of postgis (and also spatialite) will return also the removed parts of original geometry. (point , arc or other it was) This could be an issue, where a multi-geometry is return for a single input. It seems this could be overcome with some checks, and eventually fallback to rejecting the geometry, if necessary. The MakeValid is capable to resolve very complex situations, the main goal is never lost any vertex. So the MakeValid in the Postgs often could return a geometrycollection with one, two or three parts (polygons, linea and points). As example when the invalidity is a line inside a polygon (this is quite normal when the geometries came from cad systems), the MakeValid will create a collection with the polygon and a line. In Spatialite instead the collection are not so flexible so the solution was to wrap the MakeValid on two distinct functions: MakeValid() and MakeValidDiscarded. To not lost of view the original geometry. Sorry. I don't understand your meaning here. Sorry, I was unable to explain. Simply I want say that the main goal of the MakeValid was to resolve an invalidity withoun lost any vertex of the original geometry. In spatialite where the collection are no so flexible. The solution was to support two functions one to return the higher level geometry (usually the more interesting to see) and another function (MakeValidDiscarded) to return the lower level geometries. But this mean that using only the ST_MakeValid() in spatialite without see what return the MakeValidDiscarded Function could mean to lost something. Regards, Andrea. Regards, Larry __**_ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/**mailman/listinfo/qgis-**developerhttp://lists.osgeo.org/mailman/listinfo/qgis-developer -- - Andrea Peri . . . . . . . . . qwerty àèìòù - ___ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-developer
Re: [Qgis-developer] Labels on topologically wrong polygons
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Il 25/07/2013 01:57, William Kyngesburye ha scritto: If liblwgeom becomes a requirement for QGIS, I'll certainly be packaging it with QGIS, and adding instructions to INSTALL. it is not a requirement, but it wouold be good if you could include it anyway, to let osx users enjoy our plugin. It probably requires a full install of Postgres. it should not; at least, o win and deb this is not the case. re: this discussion, see also: http://hub.qgis.org/issues/4079 all the best, and thanks. - -- Paolo Cavallini - Faunalia www.faunalia.eu Full contact details at www.faunalia.eu/pc Nuovi corsi QGIS e PostGIS: http://www.faunalia.it/calendario -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Icedove - http://www.enigmail.net/ iEYEARECAAYFAlHwtSwACgkQ/NedwLUzIr6vyACgoAuq2d67cNsuxcgITMu+jmNB mp4An0wM13qFGdAuMhgpsTTd44SZ4Qth =0Bk4 -END PGP SIGNATURE- ___ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-developer
