Re: [osg-users] dimension oh a model
That's why I still like Openflight Models they have their units it the header :) ( Plus I can use Creator quite well :) ) One way I also solve this is to have a sidecar file that has the units of the model(once known) if the format does not supported and then I process the sidecar along with the model file etc. Gordon Tomlinson 3D Technical Product Manager Overwatch(r) An Operating Unit of Textron Systems __ -Original Message- From: osg-users-boun...@lists.openscenegraph.org [mailto:osg-users-boun...@lists.openscenegraph.org] On Behalf Of Paul Martz Sent: Friday, August 12, 2011 3:50 PM To: osg-users@lists.openscenegraph.org Subject: Re: [osg-users] dimension oh a model On 8/12/2011 11:11 AM, Sanat Talmaki wrote: Hi Paul, Sorry for my late reply to your post. That is a very good point you bring up about the units of different objects in a scene. When one uses data from USGS in VPB to create a terrain, the rest of the objects have to be scaled up or down to represent their real world size prior to be being used in the scene... But the confusion for me arises when say I load a truck in osg and its dimensions are (12, 6, 8) = (L,W,H). (don't know what units these are in) Without knowing the units of the model (whether 12 feet/meters), how does one apply a scaling factor? As I said in my previous post, if you don't have access to any metadata that tells you what the units are, there's no way for your software to handle this in an automated way. You must either manually scale the model to fit your application coordinate system, or you must manually create some metadata. In the case you cite, both options would be based entirely on guesswork. -Paul ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.or g ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] dimension oh a model
Hi Paul, Sorry for my late reply to your post. That is a very good point you bring up about the units of different objects in a scene. When one uses data from USGS in VPB to create a terrain, the rest of the objects have to be scaled up or down to represent their real world size prior to be being used in the scene... But the confusion for me arises when say I load a truck in osg and its dimensions are (12, 6, 8) = (L,W,H). (don't know what units these are in) Without knowing the units of the model (whether 12 feet/meters), how does one apply a scaling factor? I'm not sure if I have explained my point well enough. I can try and re-post if that is the case. Thanks Sincerely, Sanat -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=42038#42038 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] dimension oh a model
On 8/12/2011 11:11 AM, Sanat Talmaki wrote: Hi Paul, Sorry for my late reply to your post. That is a very good point you bring up about the units of different objects in a scene. When one uses data from USGS in VPB to create a terrain, the rest of the objects have to be scaled up or down to represent their real world size prior to be being used in the scene... But the confusion for me arises when say I load a truck in osg and its dimensions are (12, 6, 8) = (L,W,H). (don't know what units these are in) Without knowing the units of the model (whether 12 feet/meters), how does one apply a scaling factor? As I said in my previous post, if you don't have access to any metadata that tells you what the units are, there's no way for your software to handle this in an automated way. You must either manually scale the model to fit your application coordinate system, or you must manually create some metadata. In the case you cite, both options would be based entirely on guesswork. -Paul ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] dimension oh a model
I've had this problem before with models that are unit-less. I just manually scaled the models (as Paul suggests) until they looked right based on landmarks in the database where the sizes were known. It's an empirical approach but it's the best you can really do if you don't know the units of the model. -Shayne -Original Message- From: osg-users-boun...@lists.openscenegraph.org [mailto:osg-users-boun...@lists.openscenegraph.org] On Behalf Of Paul Martz Sent: Friday, August 12, 2011 1:50 PM To: osg-users@lists.openscenegraph.org Subject: Re: [osg-users] dimension oh a model On 8/12/2011 11:11 AM, Sanat Talmaki wrote: Hi Paul, Sorry for my late reply to your post. That is a very good point you bring up about the units of different objects in a scene. When one uses data from USGS in VPB to create a terrain, the rest of the objects have to be scaled up or down to represent their real world size prior to be being used in the scene... But the confusion for me arises when say I load a truck in osg and its dimensions are (12, 6, 8) = (L,W,H). (don't know what units these are in) Without knowing the units of the model (whether 12 feet/meters), how does one apply a scaling factor? As I said in my previous post, if you don't have access to any metadata that tells you what the units are, there's no way for your software to handle this in an automated way. You must either manually scale the model to fit your application coordinate system, or you must manually create some metadata. In the case you cite, both options would be based entirely on guesswork. -Paul ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.or g ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] dimension oh a model
Coincidentally that was the approach I was going to take: Place some object of known size on my terrain and scale the unknown units object accordingly, sort of digitally 'eyeballing' it. This empirical approach seems to be the most appropriate way when dealing with objects of unknown units that need to be used with other objects/terrain of a known size ( units). Thanks Sincerely, Sanat -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=42042#42042 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] dimension oh a model
It has worked for us just fine in the absence of data. Good luck with your effort... -Shayne -Original Message- From: osg-users-boun...@lists.openscenegraph.org [mailto:osg-users-boun...@lists.openscenegraph.org] On Behalf Of Sanat Talmaki Sent: Friday, August 12, 2011 2:59 PM To: osg-users@lists.openscenegraph.org Subject: Re: [osg-users] dimension oh a model Coincidentally that was the approach I was going to take: Place some object of known size on my terrain and scale the unknown units object accordingly, sort of digitally 'eyeballing' it. This empirical approach seems to be the most appropriate way when dealing with objects of unknown units that need to be used with other objects/terrain of a known size ( units). Thanks Sincerely, Sanat -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=42042#42042 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.or g ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] dimension oh a model
Hi David, I guess I am replying to a rather old post, but I'll try my luck anyway: Adding to your post on getting the size of the terrain, I had a similar question in mind. For a given terrain model (built using osgeart/vpb etc), is there a way to ensure that models loaded on the terrain conform to the scale of the terrain. If I loaded a building model onto a terrain, unless I knows the size of the terrain and the dimensions/scaling it is conforming to, my building model may be unrealistically big/small not representing reality. I was searching along these lines and came across your post and just wanted to check if you had found any tool that helps you do this (getting terrain size) Thanks Sincerely, Sanat -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=41951#41951 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] dimension oh a model
In response to David's post (which I didn't see until now), it's fairly straightforward to back-transform a pixel into world coordinates. I've posted on this in the past, email me offline and I'll send you more info about it. Sanat, one thing I learned in the GIS classes years ago is that you must be very careful to have all of your GIS data in the same projection/ellipsoid/units, or they won't mix well. If your buildings are too large, then perhaps they were modeled in feet and your Earth is modeled in meters, for example. If you don't have any meta data for the models to tell your application what coordinate system and units the model uses, there is no magic software trick to handle that situation. So you have two solutions: Either manually put all your models (Earth and buildings) into the same coordinate system and units, or manually ensure that each model contains the necessary metadata so that your application can transform them as needed into a common coordinate system and units. -Paul On 8/9/2011 10:24 AM, Sanat Talmaki wrote: Hi David, I guess I am replying to a rather old post, but I'll try my luck anyway: Adding to your post on getting the size of the terrain, I had a similar question in mind. For a given terrain model (built using osgeart/vpb etc), is there a way to ensure that models loaded on the terrain conform to the scale of the terrain. If I loaded a building model onto a terrain, unless I knows the size of the terrain and the dimensions/scaling it is conforming to, my building model may be unrealistically big/small not representing reality. I was searching along these lines and came across your post and just wanted to check if you had found any tool that helps you do this (getting terrain size) Thanks Sincerely, Sanat -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=41951#41951 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org -- -Paul Martz Skew Matrix Software http://www.skew-matrix.com/ ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
[osg-users] dimension oh a model
Hi, how can I retrieve the dimension of an OSG model loaded in the scene? I see that with getBound().radius() I can retrieve informations about the BoundingSphere. But I need also the three dimensions.. Thanks! -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=27354#27354 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] dimension oh a model
daniele argiolas writes: Hi, how can I retrieve the dimension of an OSG model loaded in the scene? I see that with getBound().radius() I can retrieve informations about the BoundingSphere. But I need also the three dimensions.. Hi Daniele, Assuming that no transformation nodes exist in the graph describing your node, you can write a node visitor that joins all the bounding boxes of every geode. Else you'll need to modify every bounding box by its parent transforms in order to join them. -- Alberto ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] dimension oh a model
Hi Daniele, Alberto, Assuming that no transformation nodes exist in the graph describing your node, you can write a node visitor that joins all the bounding boxes of every geode. Else you'll need to modify every bounding box by its parent transforms in order to join them. Actually you don't need to write this, it's so common that it exists in OSG already: osg::ComputeBoundsVisitor. And it does the right thing with transforms. osg::ComputeBoundsVisitor cbbv; node-accept(cbbv); osg::BoundingBox bb = cbbv.getBoundingBox(); osg::Vec3 size = bb._max - bb._min; // Then size contains the size in X, Y and Z. Hope this helps, J-S -- __ Jean-Sebastien Guayjean-sebastien.g...@cm-labs.com http://www.cm-labs.com/ http://whitestar02.webhop.org/ ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] dimension oh a model
Jean-Sébastien Guay wrote: Hi Daniele, Alberto, Assuming that no transformation nodes exist in the graph describing your node, you can write a node visitor that joins all the bounding boxes of every geode. Else you'll need to modify every bounding box by its parent transforms in order to join them. Actually you don't need to write this, it's so common that it exists in OSG already: osg::ComputeBoundsVisitor. And it does the right thing with transforms. osg::ComputeBoundsVisitor cbbv; node-accept(cbbv); osg::BoundingBox bb = cbbv.getBoundingBox(); osg::Vec3 size = bb._max - bb._min; // Then size contains the size in X, Y and Z. For purposes of analyzing models, it's often useful to have access to this information from the command line. The osgWorks project (osgworks.googlecode.com) contains the osgwbvv application to display bounding volume information, either as a sphere or (using ComputeBoundsVisitor) as a box. osgwbvv cow.osg Sphere: Center 0.776125 -0.43866 0 Radius 6.35558 osgwbvv --box cow.osg Box: Center 0.776125 -0.43866 0 Radius 6.35558 Extents 10.4439 3.40282 6.39676 The bounding volume (sphere or box) is also displayed graphically as line geometry around the model. -- -Paul Martz Skew Matrix Software http://www.skew-matrix.com/ ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] dimension oh a model
Paul Martz writes: Jean-Sébastien Guay wrote: Hi Daniele, Alberto, Assuming that no transformation nodes exist in the graph describing your node, you can write a node visitor that joins all the bounding boxes of every geode. Else you'll need to modify every bounding box by its parent transforms in order to join them. Actually you don't need to write this, it's so common that it exists in OSG already: osg::ComputeBoundsVisitor. And it does the right thing with transforms. osg::ComputeBoundsVisitor cbbv; node-accept(cbbv); osg::BoundingBox bb = cbbv.getBoundingBox(); osg::Vec3 size = bb._max - bb._min; // Then size contains the size in X, Y and Z. For purposes of analyzing models, it's often useful to have access to this information from the command line. The osgWorks project (osgworks.googlecode.com) contains the osgwbvv application to display bounding volume information, either as a sphere or (using ComputeBoundsVisitor) as a box. osgwbvv cow.osg Sphere: Center 0.776125 -0.43866 0 Radius 6.35558 osgwbvv --box cow.osg Box: Center 0.776125 -0.43866 0 Radius 6.35558 Extents 10.4439 3.40282 6.39676 The bounding volume (sphere or box) is also displayed graphically as line geometry around the model. Hi J-S, Paul, how could I have missed this! Thank you for the tips :) ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] dimension oh a model
It works!!! Thank you very much! Daniele -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=27371#27371 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] dimension oh a model
Alberto Luaces wrote: how could I have missed this! Thank you for the tips :) OSG is big. :-) -- -Paul Martz Skew Matrix Software http://www.skew-matrix.com/ ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] dimension oh a model
Paul Martz wrote: Alberto Luaces wrote: how could I have missed this! Thank you for the tips :) OSG is big. :-) -- -Paul Martz Skew Matrix Software http://www.skew-matrix.com/ ___ osg-users mailing list http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org -- Post generated by Mail2Forum Hi Paul and J-S! While we are on the subject, let’s turn this inside out for a moment! :? If say, I was looking at a chunk of the earth on a globe (Assuming that you have it dimensioned out properly) You know altitude your camera is from the surface (assuming that its the same as the theoretical ellipsoid) and you want to know the distance (width and height) of the territory you are covering (in the view of your camera) is there a function in OSG that does that? D Glenn D Glenn (a.k.a David Glenn) - Join the Navy and See the World ... from your Desk! -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=27400#27400 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
