Re: [osg-users] Tesselator.cpp build error on MacOS X

Hi Philip, Philip Lowman wrote: Can you do an svn update to the latest and configure a fresh build tree on your OSX system (either nuke your out-of-source build tree or delete CMakeCache.txt) then try building osgUtil again? I believe this issue All good now. I cleaned my build directory

[osg-users] updateTraversal and camera manipulator

Hi, In our application, I need to get the cameraViewMatrix in the updateTraversal. I have done that with an update callback. But I think I have the ViewMatrix of the last frame, not the current frame, because of some graphics problems. I have look in Viewer::updateTraversal() and I have found

Re: [osg-users] Shapefile troubles

(I posted these earlier but it got moderated out... no file attachment this time) Could anybody have a look at these shapefiles? It should be a network of roads but I can't get the shp plugin to read it correctly. http://www.wikiupload.com/download_page.php?id=33045 ~300KB zip

Re: [osg-users] Problem with osgviewerGTK example

Hello, I checked the lighting and that is not the problem. But I tried to implement a osgViewer::Viewer in the application (after the gtk main loop). Now I have the same problem in the osgViewer. But the cessna.osg looks fine, when I comment all GTK stuff out. Ergo, I think the problem is

Re: [osg-users] How to document osgShadow?

Hi Ben, Many thanks for offering to pitch in on the documentation side, not at all the easiest tasks but valued no less. A mixture of Programming Guide style articles and Doxygen Docs are good ways, going the tutorial route is another. Tweaking the osgshadow example so its more useful for

Re: [osg-users] Building the SVG plugin

Hi Paul, As JS, Ulrich and Philip has mentioned at present the dependency checking code relies upon pkg-config, which isn't standard under Windows. For Windows we'll need write our won FindCario and FindRSVG.cmake files such as the ones we already have in OpenSceneGraph/CMakeModules. Robert.

Re: [osg-users] updateTraversal and camera manipulator

Hi Christophe, There is a reason why ViewerBase::updateTraversals() is a virtual function :-) Basically different applications will have different requirements w.r.t set up and use of the view matrix, most apps they won't be dependant on each other, other applications will have a view matrix

Re: [osg-users] window

On Tue, May 13, 2008 at 8:33 AM, Miriam D'Elia [EMAIL PROTECTED] wrote: Hi Robert, we apologise, but only yesterday I noticed that pressing the button f you switch from full-screen display to display in a window. osgProducer::Viewer is a everything and the kitchen sink viewer so does contain

Re: [osg-users] pagedLOD question

HI Brett, What I have done VirtualPlanetBuilder is to have a quad tree scene graph structure like: Group PagedLOD child 0 - local tile geometry at low resolution child 1 - external file reference PagedLOD child 0 - local tile geometry at low resolution

Re: [osg-users] How to document osgShadow?

Alright. I have created a wiki page here, with my best attempt at documenting what i've learned so far: http://www.openscenegraph.org/projects/osg/wiki/Support/ProgrammingGuide/osgShadow It would be really great if someone who actually /knows/ the code could fill in things like: * How do

Re: [osg-users] Problem with osgviewerGTK example

Sorry, I make a misstake. I have the 2.12.5 of gtk and I updated it to 2.12.9. But I it doesn't works. And I found out it works fine on Windows XP. It works on Windows and on Kubuntu, but not on Fedora 8. The gtk_init(...) and the osgViewer are incompatible on Fedora 8??? Cheers, Martin

Re: [osg-users] Problem with osgviewerGTK example

Hi Martin, I just tried your example and it works fine on my Kubuntu 7.10 system pkg-config gtk+-2.0 --modversion 2.12.0 Perhaps your version of gtk is screwing up X11 in a way that the osgViewer::Viewer's own creation of windows is going astray. Robert. On Tue, May 13, 2008 at 9:26 AM,

Re: [osg-users] updateTraversal and camera manipulator

ok, thanks for the explanation ! 2008/5/13 Robert Osfield [EMAIL PROTECTED]: Hi Christophe, There is a reason why ViewerBase::updateTraversals() is a virtual function :-) Basically different applications will have different requirements w.r.t set up and use of the view matrix, most apps

Re: [osg-users] Problem with PrecipitationEffect

Hi all, So I have tested the osgPrecipitationEffect with the osgQT exemples, and it works fine with all except the one using CompositeViewer in AdapterWidget.cpp The rain effect is here, but there is no animation. In the two cases, there is the osgViewer::GraphicsWindowEmbedded in one it works, so

Re: [osg-users] How to document osgShadow?

Ben Discoe wrote on Tuesday 13 May 2008: SSM definitely does not work on my (fairly old) ATI Radeon 9800, perhaps this is due to needing some specific modern shader capability? On my harware (ATI mobility X300), only -st (shadow texture) works. From an earlier thread: Jean-Sébastien Guay

[osg-users] osgthirdpersonview example: anyone else with an ATI having problems?

On my new system, with a crappy ATI card, the osgthirdpersonview example in 2.4 is showing two black windows and doesn't respond to any inpu. stracing the process seems to suggest some threading-related problem. On the NVidia-systems I tried it on it works fine, so would this be an ATI-related

Re: [osg-users] Compile OSG with Eclipse IDE

On Wed, May 7, 2008 at 12:45 PM, David Jurado [EMAIL PROTECTED] wrote: Good morning, I need help, I am trying to compile OSG, but I can't. My IDE is Eclipse Platform Version: 3.3.2. When I try to build this project, it show the following messages: Build of configuration Debug for

Re: [osg-users] Shapefile troubles

The file looked fine for me, but I've written my own Shapefile reader...so it's probably an issue in the shp plugin. Your shapefile has PolyLineZ shapes if that helps in debugging. - Donny On Tue, May 13, 2008 at 3:08 AM, Kimmo Kotajärvi [EMAIL PROTECTED] wrote: (I posted these earlier but

[osg-users] OSG tutorials for newbies available

Hi everyone, I can now confirm that all my tutorials and source codes have been uploaded to the official website in the appropriate section. These tutorials are designed for Linux users but Windows beginner developers can still use. It is very straightforward to port the source codes to

Re: [osg-users] osgthirdpersonview example: anyone else with an ATI having problems?

Hi, Robert Osfield wrote: To see if it is thread related try : osgthirdpersonview cow.osg --SingleThreaded You could also see if its FSAA causing the problems by comment out the line: // Turn on FSAA, makes the lines look better. osg::DisplaySettings::instance()-setNumMultiSamples( 4

Re: [osg-users] GDAL plugin functionalities in OSG-2.4 ?

Thanks Robert, I tried reading sample.dem file in my sample program using osgDB::readImageFile(), but not able to open it (with the warning could not find plugin ), did my assumption of reading the .dem file as image is correct or do i need to read the gdal supported files differently. RJ

Re: [osg-users] Shapefile troubles

Kimmo, These are Polyline ZM shapes; The X,Y value are in degrees, and my guess is that the shp plugin is interpreting the Z value as degrees as well (when it's probably meters). Anyway, the WKT will not convey the units for Z coordinates, so maybe the shp plugin needs (or has) a parameter for

Re: [osg-users] osgthirdpersonview example: anyone else with an ATI having problems?

Hi Paul, To see if it is thread related try : osgthirdpersonview cow.osg --SingleThreaded You could also see if its FSAA causing the problems by comment out the line: // Turn on FSAA, makes the lines look better. osg::DisplaySettings::instance()-setNumMultiSamples( 4 ); Robert. On

[osg-users] problems with normals

Dear all, I'm having a problem when importing an OBJ model. I load the v positions (vertices), the indices and the vn positions (normals). Then I create a geometry with these data. I'm having a bad result (see image attached), it is like the normals are not well defined. I have the same

Re: [osg-users] Problem with osgviewerGTK example

I set OSG_NOTIFY_LEVEL on DEBUG and compare the application with gtk and without gtk and I found the following differences. With GTK: glVersion=2, isGlslSupported=YES, glslLanguageVersion=1 Without GTK: glVersion=2.1, isGlslSupported=YES, glslLanguageVersion=1.2 I still use OSG 2.2, because

Re: [osg-users] problems with normals

El Martes 13 Mayo 2008ES 13:59:45 lucas Grijander escribió: Dear all, I'm having a problem when importing an OBJ model. I load the v positions (vertices), the indices and the vn positions (normals). Then I create a geometry with these data. I'm having a bad result (see image attached), it is

Re: [osg-users] problems with normals

Hi, I've created the OBJ file with 3DStudio, and I've verified that all the normals are pointing out, so it should work anyway? I think it depends on the way I'm reading the data... From: [EMAIL PROTECTED] To: osg-users@lists.openscenegraph.org Date: Tue, 13 May 2008 14:13:12 +0200

Re: [osg-users] problems with normals

lucas Grijander wrote: Hi, I've created the OBJ file with 3DStudio, and I've verified that all the normals are pointing out, so it should work anyway? I think it depends on the way I'm reading the data... So does OSG's .obj reader show the correct results? Paul From: [EMAIL

Re: [osg-users] Problem with osgviewerGTK example

On Tue, May 13, 2008 at 1:09 PM, Martin Großer [EMAIL PROTECTED] wrote: I set OSG_NOTIFY_LEVEL on DEBUG and compare the application with gtk and without gtk and I found the following differences. With GTK: glVersion=2, isGlslSupported=YES, glslLanguageVersion=1 Without GTK:

Re: [osg-users] problems with normals

lucas Grijander wrote: yes, i tried with the OSG reader and it works. So it should be something concerning the format of the data? More likely your interpretation of the data. Did you check against the .obj specification (as far as there is one, other than from old Alias documentation),

[osg-users] compiling 2.4 problems

With Windows XP, I tried to Cmake and then compile with VC 2008 OSG 2.4 but I get the linking errors: LNK1104: cannot open file '..\..\lib\OpenThreadsd.obj' It seems that for some reason it does not look for .libs but for .obj's. How to create a version that uses libs instead of objs?

Re: [osg-users] GDAL plugin functionalities in OSG-2.4 ?

Hi Rahul, There isn't any extension aliasing from .dem to .gdal built into osgDB::Registry so there is no way for the OSG to know that you intend to use the gdal plugin. You add these yourself if you wish. You can get the OSG to use the gdal plugin by preloading the plugin, then it'll be called

Re: [osg-users] compiling 2.4 problems

This was discussed recently, check the archives. Bottom line is that there are some compatibility issues between CMake 2.6 and our CMake macros (designed for CMake 2.4.x). Best solution for now is to back out your CMake to 2.4.8. -Paul _ From: [EMAIL PROTECTED] [mailto:[EMAIL

Re: [osg-users] wxWidgets onKeyDown Event not called

Has anyone been able to get the keyboard handlers to work within the osgViewerWx example? -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Steven Powers Sent: Monday, May 12, 2008 11:53 AM To: OpenSceneGraph Users Subject: [osg-users] wxWidgets

Re: [osg-users] How to document osgShadow?

Hi Ben -- To underscore the comments of others on this thread, I add the following: * For reference -style documentation, embedding Doxygen comments is probably the best approach. Doxygen excels at creating reference-style documentation. The other benefit of embedding documentation in the code

Re: [osg-users] Camera

Robert Osfield ha scritto: Hi Robert, I want to move with a camera in the scene. The scene must not move. Miriam Hi Miriam, On Tue, May 13, 2008 at 2:08 PM, Miriam D'Elia [EMAIL PROTECTED] wrote: I would like to insert in my scene a camera that moves by pressing the arrow buttons

Re: [osg-users] problems with normals

El Martes 13 Mayo 2008ES 14:17:58 lucas Grijander escribió: Hi, I've created the OBJ file with 3DStudio, and I've verified that all the normals are pointing out, so it should work anyway? I think it depends on the way I'm reading the data... Is your model made of quads? It could be that you

Re: [osg-users] wxWidgets onKeyDown Event not called

Yes. The example included in OSG need a little fix to make the 's' (statistics) handler work. If you want I can send you an example. Ciao! mario Steven Powers wrote: Has anyone been able to get the keyboard handlers to work within the osgViewerWx example? -Original

Re: [osg-users] wxWidgets onKeyDown Event not called

Yes Please do. I remember reading from the archives that it was sending 'S' rather than 's'. But I think my problem might be different. I cant get the OnKeyDown Method to be called at all. When I place breakpoints inside of the function they are never hit. -Original Message- From:

Re: [osg-users] Camera

As Robert suggested see the osgGA::DriveManipulator or osgGA::UFOManipulator -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Miriam D'Elia Sent: Tuesday, May 13, 2008 9:48 AM To: OpenSceneGraph Users Subject: Re: [osg-users] Camera Robert Osfield ha

Re: [osg-users] Problem with osgviewerGTK example

I'm not the admin, that is my problem. How can I check the vendor string? Cheers, Martin Original-Nachricht Datum: Tue, 13 May 2008 13:35:41 +0100 Von: Robert Osfield [EMAIL PROTECTED] An: OpenSceneGraph Users osg-users@lists.openscenegraph.org Betreff: Re: [osg-users]

Re: [osg-users] problems with normals

Alberto Luaces wrote: El Martes 13 Mayo 2008ES 14:17:58 lucas Grijander escribió: Hi, I've created the OBJ file with 3DStudio, and I've verified that all the normals are pointing out, so it should work anyway? I think it depends on the way I'm reading the data... Is your model made

Re: [osg-users] [Blender and OSG]

Hi Maybe Blender can export into .3ds or .obj file ? 2008/5/13 Jean-Baptiste Authesserre [EMAIL PROTECTED]: Hi, I would like to use blender to create my 3D models. Is that possible to use blender files .blend with osg? I compiled by myself osg by using Cmake for the configuration of the

[osg-users] CMake debug extension d CMAKE_DEBUG_POSTFIX

Hi Robert, I would like to build debug version of osg without d extension everywhere, here my case: I build osg in release and debug in two separate directory, then when i want to debug my application i change my library path, and then i rebuild the application. So it works when i have no

Re: [osg-users] [Blender and OSG]

I was aware of blender -osg export, see http://projects.blender.org/projects/osgexport/ not sure if it is the most up to date Jean-Baptiste Authesserre wrote: Hi, I would like to use blender to create my 3D models. Is that possible to use blender files .blend with osg? I compiled by

Re: [osg-users] [Blender and OSG]

No one except the Blender developers know what a .blend file is, and even they can't really even explain much about it. I've tried many times in the past to wrap my head around its binary format, but it's seriously the very definition of moving target. Besides, if you asked the Blender developers

Re: [osg-users] Building the SVG plugin

Hi Paul, As JS, Ulrich and Philip has mentioned at present the dependency checking code relies upon pkg-config, which isn't standard under Windows. For Windows we'll need write our won FindCario and FindRSVG.cmake files such as the ones we already have in OpenSceneGraph/CMakeModules.

Re: [osg-users] CMake debug extension d CMAKE_DEBUG_POSTFIX

Hi Cedric, I'm open to make the d suffix optional. It exits on all platforms purely to keep things consistent, and in the case with Windows one can't mix debug and release libs so one is really forced into this nonsense so this is where the convention was dictated from. Robert. On Tue, May 13,

Re: [osg-users] [Blender and OSG]

Thank you for these quick answers. Blender can export in .3ds file, but it is the use of this export function I would like to avoid. In fact I observed that if I save my 3D objects in blender format and then open the file .blend, there is no problem, my objects have kept the transform properties

Re: [osg-users] [Blender and OSG]

Hi, On Tuesday 13 May 2008 16:57, Jean-Baptiste Authesserre wrote: I would like to use blender to create my 3D models. Is that possible to use blender files .blend with osg? I compiled by myself osg by using Cmake for the configuration of the Visual studio project. I found no mention about

Re: [osg-users] [Blender and OSG]

hello, see also the bottom of this page of delta3D. http://www.delta3d.org/article.php?story=20051207101455773topic=docs rgds jp Jean-Baptiste Authesserre wrote: Hi, I would like to use blender to create my 3D models. Is that possible to use blender files .blend with osg? I compiled by

Re: [osg-users] [Blender and OSG]

Am Dienstag, 13. Mai 2008 17:15:36 schrieb Mathias Fröhlich: Hi, On Tuesday 13 May 2008 16:57, Jean-Baptiste Authesserre wrote: I would like to use blender to create my 3D models. Is that possible to use blender files .blend with osg? I compiled by myself osg by using Cmake for the

Re: [osg-users] osgWidget 0.1.8 (pre-merge)

Thanks Jeremy for your work! Trying osgwidgetinput I receive the following warnings on Linux with latest SVN. At least one of them could be stopped if you could provide the missing font Calibri1.ttf . Is it possible? Ciao! mario isone

Re: [osg-users] [Blender and OSG]

Thanks a lot! Has anybody an Idea of which 3D file format can be used with OSG (other than 3DS)? Because blender can export in many formats... Else I would test your suggestions... 2008/5/13 Benjamin Eikel [EMAIL PROTECTED]: Am Dienstag, 13. Mai 2008 17:15:36 schrieb Mathias Fröhlich: Hi,

Re: [osg-users] osgWidget 0.1.8 (pre-merge)

On Tue, 2008-05-13 at 17:26 +0200, Mario Valle wrote: Thanks Jeremy for your work! Trying osgwidgetinput I receive the following warnings on Linux with latest SVN. At least one of them could be stopped if you could provide the missing font Calibri1.ttf . Is it possible? Ciao!

[osg-users] [Blender and OSG]

Hi, I would like to use blender to create my 3D models. Is that possible to use blender files .blend with osg? I compiled by myself osg by using Cmake for the configuration of the Visual studio project. I found no mention about blender during this configuration step. After the compilation, there

Re: [osg-users] [Blender and OSG]

Am Dienstag, 13. Mai 2008 17:29:05 schrieb Jean-Baptiste Authesserre: Thanks a lot! Has anybody an Idea of which 3D file format can be used with OSG (other than 3DS)? Because blender can export in many formats... Else I would test your suggestions... Hello, have a look at the list:

Re: [osg-users] osgWidget 0.1.8 (pre-merge)

Hi Jeremy I've just tried to compile your code using Visual Studio 9.0 and got lots of errors that are almost all related to 'const' usage. I am sometime suspicious about Redmond compilers so I also tried to compile the code on Debian 4.0, and the errors are (hopefully) similar. Here is the

Re: [osg-users] osgWidget 0.1.8 (pre-merge)

On Tue, 2008-05-13 at 17:49 +0200, Thibault Genessay wrote: Hi Jeremy I've just tried to compile your code using Visual Studio 9.0 and got lots of errors that are almost all related to 'const' usage. I am sometime suspicious about Redmond compilers so I also tried to compile the code on

Re: [osg-users] Robert, collada dae2 maybe?

Yeah that's pretty weird. I doubt this is a result of upgrading to DOM 2.1. The Collada plugin has probably always had these problems, though I could be mistaken. Robert Osfield wrote: 2008/5/13 [EMAIL PROTECTED]: I submitted a fix to osg-submissions. Diff (against trunk) is below for

Re: [osg-users] DelaunayTriangulator's Input Point Array

On Tue, May 13, 2008 at 5:28 PM, Argentieri, John-P63223 [EMAIL PROTECTED] wrote: Once the Delaunay triangulator has been run on the Vec3Array that I set at its input array, the array can't be deleted. The Delaunay triangulator must be putting something bad into that array. Any ideas? I can't

Re: [osg-users] osgWidget 0.1.8 (pre-merge)

Hi Jeremy On Tue, May 13, 2008 at 6:16 PM, Jeremy Moles [EMAIL PROTECTED] wrote: On Tue, 2008-05-13 at 17:49 +0200, Thibault Genessay wrote: Hi Jeremy I've just tried to compile your code using Visual Studio 9.0 and got lots of errors that are almost all related to 'const' usage.

Re: [osg-users] osgWidget 0.1.8 (pre-merge)

hi, fwiw, there are at least two high-quality fonts intended as freely-distributable replacements for common MS burdened fonts. Give them a shot, see how they work for you: http://en.wikipedia.org/wiki/Liberation_fonts http://en.wikipedia.org/wiki/Bitstream_Vera seems these might be a great

Re: [osg-users] How to document osgShadow?

Hi Ben, Wow, that was fast! :-) It would be really great if someone who actually /knows/ the code could fill in things like: I wouldn't claim to know the code (I have only dabbled in it to try and fix some things, not actually implemented any of it) but I had a go at adding some info to

Re: [osg-users] osgthirdpersonview example: anyone else with an ATIhaving problems?

Paul Martz wrote: Good suggestions, Robert -- Those are the most likely causes. Paul -- Is it just osgthirdpersonview that has a problem, or do you see the same issue with other CompositeViewer-based apps? -Paul (the other Paul M.) After testing some more with the default threading model

Re: [osg-users] [Blender and OSG]

Bonjour Jean-Baptiste, Thank you for these quick answers. Blender can export in .3ds file, but it is the use of this export function I would like to avoid. In fact I observed that if I save my 3D objects in blender format and then open the file .blend, there is no problem, my objects have

Re: [osg-users] osgthirdpersonview example: anyone else with an ATIhaving problems?

Hm. The code deletes one of the root node's children, and recreates it, each frame. Try making this change: osg::ref_ptr osg::Group root = new osg::Group; root-setDataVariance( osg::Object::DYNAMIC ); (The first line is already in the code; please add the second line). -Paul

Re: [osg-users] osgWidget 0.1.8 (pre-merge)

Hello Jeremy, I'd be real interested to know what version of GCC is complaining about this. I don't see this error on Fedora 8/GCC4.1, and I've never had an e-mail about it or antyhing. The code, as far as I can tell, is perfectly valid C++. Perhaps I can come up with a workaround for this, as

Re: [osg-users] [Blender and OSG]

Our best experience has been to export either as either obj or osg (using osgexport). The osgexport blender plugin has the advantage of handling animations within a single .osg file, obj handles anims as well, but produces one .obj file for each timestep. On Tue, 13 May 2008, Jean-Baptiste

Re: [osg-users] osgthirdpersonview example: anyone else with an ATIhaving problems?

Hi Paul, On Tue, May 13, 2008 at 6:33 PM, Paul Martz [EMAIL PROTECTED] wrote: Hm. The code deletes one of the root node's children, and recreates it, each frame. Try making this change: osg::ref_ptr osg::Group root = new osg::Group; root-setDataVariance( osg::Object::DYNAMIC );

Re: [osg-users] osgthirdpersonview example: anyone else with anATIhaving problems?

Hi Paul, On Tue, May 13, 2008 at 6:33 PM, Paul Martz [EMAIL PROTECTED] wrote: Hm. The code deletes one of the root node's children, and recreates it, each frame. Try making this change: osg::ref_ptr osg::Group root = new osg::Group; root-setDataVariance(

Re: [osg-users] osgWidget 0.1.8 (pre-merge)

Hi Jeremy, I wanted to try out your lib, but I have problems regarding to the cmake build system. First problem is, if you have osg installed not under standard directory. I have then manually to specify the cmake_include and cmake_lib paths. maybe you could take a look into CMake build system

Re: [osg-users] osgWidget 0.1.8 (pre-merge)

On Tue, 2008-05-13 at 20:28 +0200, Art Tevs wrote: Hi Jeremy, I wanted to try out your lib, but I have problems regarding to the cmake build system. First problem is, if you have osg installed not under standard directory. I have then manually to specify the cmake_include and cmake_lib

Re: [osg-users] osgWidget 0.1.8 (pre-merge)

On Tue, 2008-05-13 at 18:44 +0200, Thibault Genessay wrote: Hi Jeremy On Tue, May 13, 2008 at 6:16 PM, Jeremy Moles [EMAIL PROTECTED] wrote: On Tue, 2008-05-13 at 17:49 +0200, Thibault Genessay wrote: Hi Jeremy I've just tried to compile your code using Visual Studio 9.0

Re: [osg-users] DelaunayTriangulator's Input Point Array

Robert, This happenned because I forgot to choose /MD as a CRT library, in case anyone is curious. John -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Robert Osfield Sent: Tuesday, May 13, 2008 12:41 PM To: OpenSceneGraph Users Subject: Re:

[osg-users] spot_gold_cylinder silliness

(ab)using the curl plugin for up-to-the-minute gold quotes, see attached :-) -- mew -- Mike Weiblen -- Austin Texas USA -- http://mew.cx/ spot_gold_cylinder.osg Description: Binary data ___ osg-users mailing list osg-users@lists.openscenegraph.org

Re: [osg-users] spot_gold_cylinder silliness

Mike Weiblen wrote: (ab)using the curl plugin for up-to-the-minute gold quotes, see attached :-) OMG! Sell! Sell!!! ;-) /ulrich ___ osg-users mailing list osg-users@lists.openscenegraph.org