Re: [osg-users] [vpb] Geocentric Database, how to flattening area or cut out piece
On 1/14/2010 12:52 PM, Luc Claustres wrote: >> It doesn't do any blending into the surrounding areas. That's the >> higher-level >> functionality that my library adds. > Something simple I tested and which helps producing a smooth blend is to > upsample the elevation, rasterize your polygon, then downsample back to the > original resolution. > It is easy with the GDAL tools or API. Not a bad idea. I needed a configurable blend curve, so your trick (effectively a linear blend) wouldn't work for me, but good suggestion. -- Chris 'Xenon' Hanson, omo sanza lettere Xenon AlphaPixel.com PixelSense Landsat processing now available! http://www.alphapixel.com/demos/ "There is no Truth. There is only Perception. To Perceive is to Exist." - Xen ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] [vpb] Geocentric Database, how to flattening area or cut out piece
Chris 'Xenon' Hanson wrote: > > It doesn't do any blending into the surrounding areas. That's the higher-level > functionality that my library adds. > Something simple I tested and which helps producing a smooth blend is to upsample the elevation, rasterize your polygon, then downsample back to the original resolution. It is easy with the GDAL tools or API. -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=22647#22647 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] [vpb] Geocentric Database, how to flattening area or cut out piece
On 1/14/2010 10:16 AM, Torben Dannhauer wrote: > Hi, > is it possible to specifiy my polygon outline position and elevation, and > GDAL rasterize code will interpolate correctly that this area is really > flattend? I'm not really sure what you're asking. > or does it lift up/sink sown all coordinates inside the polygon to the > specified value? This is what it does. You specify the BURN_VALUE_FROM_Z option and it no longer uses a constant value for a fill, rather it uses the Z value from the polyline/polygon. In the case of the polygon, it uses the value from the first vertex since interpolating non-constant values across a polygon interior is computationally messy. In the case of a polyline, it can use varying Z values from each vertex, interpolated linearly. It doesn't do any blending into the surrounding areas. That's the higher-level functionality that my library adds. > How can I access the new API if now available via rasterize? Look at the GDAL rasterize API in the latest GDAL subversion checkout. I think GDAL 1.7 will have the new feature once it's released publicly. > Thank you, > Torben -- Chris 'Xenon' Hanson, omo sanza lettere Xenon AlphaPixel.com PixelSense Landsat processing now available! http://www.alphapixel.com/demos/ "There is no Truth. There is only Perception. To Perceive is to Exist." - Xen ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] [vpb] Geocentric Database, how to flattening area or cut out piece
Hi, is it possible to specifiy my polygon outline position and elevation, and GDAL rasterize code will interpolate correctly that this area is really flattend? or does it lift up/sink sown all coordinates inside the polygon to the specified value? How can I access the new API if now available via rasterize? Thank you, Torben -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=22632#22632 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] [vpb] Geocentric Database, how to flattening area or cut out piece
On 1/14/2010 1:43 AM, Luc Claustres wrote: >> Is it possible to flatten the geocentric database at specific coordiantes, >> or cut out speciffic areas, so the gap can be refilled with a completely >> flat area? > Maybe you could also directly alter your input data with the GDAL rasterizer > tool : http://www.gdal.org/gdal_rasterize.html I recently helped add support for GDAL rasterizing to the Z elevation of a polyline and polygon to the underlying GDAL rasterize code. I'm not sure this new functionality is accessible through the GDAL rasterize utility program yet, but this API is what my terrain deformation library uses internally. -- Chris 'Xenon' Hanson, omo sanza lettere Xenon AlphaPixel.com PixelSense Landsat processing now available! http://www.alphapixel.com/demos/ "There is no Truth. There is only Perception. To Perceive is to Exist." - Xen ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] [vpb] Geocentric Database, how to flattening area or cut out piece
zonk wrote: > Hi, > Is it possible to flatten the geocentric database at specific coordiantes, or > cut out speciffic areas, so the gap can be refilled with a completely flat > area? > Maybe you could also directly alter your input data with the GDAL rasterizer tool : http://www.gdal.org/gdal_rasterize.html -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=22593#22593 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] [vpb] Geocentric Database, how to flattening area or cut out piece
Hi, Can you publish your code where to access the elevation data? At the moment I try to calculate how much the elevation differenz to the elipsoid must be to get a flat. Thank you and merry Christmas, Torben -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=21834#21834 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] [vpb] Geocentric Database, how to flattening area or cut out piece
Hi, Well, now I don't understand the different between your loader/saver and your .modifyterrain and your "pseudo loader/saver I suppose your "what-elevation-should-I-put-here" LOADER callback is for modifying terrain on the fly during visualization What ist your callback SAVER for?= creating terrain with VPB? I think the problem is divided in to seperate aspects: a) building an interface to OSG / VPB to modify terrain elevation b) more or less sophisticated algorithms to determine what the desired elevation of a specifiy coordinate should be ( maybe only lifting/sinking, mybe smoothing like osgTDS does) Is your available code now compatible with osg 2.9.5, oder is it any old styled (you mentioned something abould a code which hast to be adapted) The background of my project: I develope a visualization for flight simulators, focused on research simulators. I am allowed to publish the whole project as open source, so when I'm finished, i will post it as a new nodekit. The porject is different from flightgear, because it is focused on the aspects of a flightsimulator, not a game ( framerate,, lights must be specific, multichannel projection with softedge blending, HAT/HOT/Collision query interface,etc.etc.etc.) The data like airports and orthophoto is of course commercial und won't be posted in any way, but maybe screenshots... The terrain modification is requiered because the airports need to be settled at flat terrain. so my problem consist of two aspects; a) interface to osg/VPB to control elevation b) algorithm to determine my desired algorithm. Just setting the elevation to a constant value is NOT enough because surface is curved and would cause an elevation error of about 4m on a 10km long airport. Because my project is academic, I have no budget for developement work, but I would like to participate work packages to create an open source solution of my problem. If you introduce me in your solution of the elevation modifikation, I'll try to implement a solution for the question how height area must be. Best regards, Torben -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=21364#21364 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] [vpb] Geocentric Database, how to flattening area or cut out piece
On 12/11/2009 3:55 PM, Torben Dannhauer wrote: > Hi, > yes, a simple rectangular region would be enough. > Does your algorithm determine the "height" of your flattend area itself by > the selected area, or do you specify a destination height and you lift/sink > your rectangular area to this level? > I'm interested in both methods. Some models are always on, so in best case > this flattening is compiled into DB to save rendering time. Additionally some > models are inserted on demand on free coordinates, so this flattening would > be great.. > Is your feature closed source or is it planned to integrate it into VPB? Well, the code I can release now is simply the "what-elevation-should-I-put-here" callback for the loader/saver. It provides you with the location and current elevation and you can return a new elevation. but, obviously for simple rectangular regions it's easy for you to determine if you're within the rectangle and return a new elevation. In this case it would be more like your "or do you specify a destination height and you lift/sink your rectangular area to this level". I provided a .modifyterrain pseudoloader/saver a while ago, but I've had to modify it since to avoid needing changes in the core OSG. I can probably provide a new version of it shortly. At the present time, it has not been selected for inclusion in core OSG, so it will probably make its home in some sort of osgTerrainTools add-on library. The deformation library that goes with this, that actually can answer the what-elevation question given some number of area or line features and additional attributes is something I'm developing for a client of mine, and the open-ness of it is an issue not yet fully determined. If this is something your organization needs, maybe we could discuss cost-sharing on the development. > Cheers, > Torben -- Chris 'Xenon' Hanson, omo sanza lettere Xenon AlphaPixel.com PixelSense Landsat processing now available! http://www.alphapixel.com/demos/ "There is no Truth. There is only Perception. To Perceive is to Exist." - Xen ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] [vpb] Geocentric Database, how to flattening area or cut out piece
Hi, yes, a simple rectangular region would be enough. Does your algorithm determine the "height" of your flattend area itself by the selected area, or do you specify a destination height and you lift/sink your rectangular area to this level? I'm interested in both methods. Some models are always on, so in best case this flattening is compiled into DB to save rendering time. Additionally some models are inserted on demand on free coordinates, so this flattening would be great.. Is your feature closed source or is it planned to integrate it into VPB? Thank you very much! Cheers, Torben -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=21356#21356 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] [vpb] Geocentric Database, how to flattening area or cut out piece
On 12/11/2009 2:20 PM, Torben Dannhauer wrote: > Hi, > I use a lowRes local database and want to add small 3D townmodels for local > areas which require a completely flat underground. Unfortunately the global > elevation model is not flat and not correct at the models area. > Is it possible to flatten the geocentric database at specific coordiantes, or > cout out speciffic areas, so the gap can be refilled with a completely flat > area? > What would be the best approach to get some areas flat? I don't know how to > reach this goal at runtime or at compile time. I have been making enhancements to VPB and OSG to support this sort of deformation. While my work is not complete, doing a trivial flatten-within-rectangular-region would not be tough for you to implement. I have made changes to support VPB terrain elevation alteration during load/save operations (through a pseudoloader) or during the initial VPB build time (via a callback). If this would work for you, I can explain more. -- Chris 'Xenon' Hanson, omo sanza lettere Xenon AlphaPixel.com PixelSense Landsat processing now available! http://www.alphapixel.com/demos/ "There is no Truth. There is only Perception. To Perceive is to Exist." - Xen ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
[osg-users] [vpb] Geocentric Database, how to flattening area or cut out piece
Hi, I use a lowRes local database and want to add small 3D townmodels for local areas which require a completely flat underground. Unfortunately the global elevation model is not flat and not correct at the models area. Is it possible to flatten the geocentric database at specific coordiantes, or cout out speciffic areas, so the gap can be refilled with a completely flat area? What would be the best approach to get some areas flat? I don't know how to reach this goal at runtime or at compile time. Thank you! Cheers, Torben -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=21350#21350 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
