Hi just for your informations
i am working on a KD-Tree based line intersection test. First result are quite better, event for the cow object with 5804 and passed 1000.0 lines trought the object with 2 real intersection we have just to check against 33 triangles instead of all (5804). B-Radius=6.35558 B-Center=0.776125,-0.43866,0 KD-Tree...[5804:1001] 5804:5804 TrianglesChecks=5804 Total Bench Time: 0.209096s C:\Dokumente und Einstellungen\adegli>"C:\Dokumente und Einstellungen\adegli\Desktop\test\Release\Test.exe" B-Radius=6.35558 B-Center=0.776125,-0.43866,0 KD-Tree...[5804:1001] 5804:5804 TrianglesChecks=33 Total Bench Time: 0.0879453s C:\Dokumente und Einstellungen\adegli> 2007/10/3, Adrian Egli <[EMAIL PROTECTED]>: > > Hi > > there are many nice project and on going project for real time ray > tracing. i would say in the future there will be many more, because > the ray tracing becomes faster and faster. The future will be a hybrid > visualisation systems: GPU / CPU and also OpenGL / RayTracing. > > Even for OSG it will become a challenge to follow such latest development > and such latest ideas, but the core concept of all such systems are quite > similar. > All systems needs a spatial data structure. In OSG the objects are > organised in bounding sphere hierarchy. And unfortunately the > primitives are just in arrays, what is may fast for rendering but for > intersection testing, tracing it's a known poor data organisation. > > (Robert) What are you thinking about this topic, just as a short general > idea. What danger do you see if we would implement a spatial hierarchic data > structure (kd-tree) to replace the array based vertex, triangles storing. > what can be a challenge or what would be quite hard to change, and where are > unknown dangers w.r.t performance for face rendering (OpenGL) ? > > /adegli > > 2007/10/2, Abe Stephens <[EMAIL PROTECTED]>: > > > > > > I'm not aware of any open source interactive ray tracers that > > vivaciously support third-party scene graphs like OSG. > > > > OpenRT (not open source) has been demoed at the Mercury booth @ > > siggraph running off a scene graph (possibly OpenInventor (?)). Razor > > (not open source) is an IRT system from UT Austin which is tightly > > integrated with its own scene graph (supports collada). We've had > > some traffic on the Manta (open source) mailing list about scene > > graph integration. The projects were all outside of Utah so I'm not > > sure if they targeted a standard tool like OSG. > > > > Abe > > > > > > On Oct 2, 2007, at 4:26 AM, osg-users- > > [EMAIL PROTECTED] wrote: > > > > > Message: 24 > > > Date: Tue, 2 Oct 2007 12:25:58 +0200 > > > From: " Tobias M?nch " <[EMAIL PROTECTED]> > > > Subject: Re: [osg-users] Searcing for raytracer implementation based > > > on OSG > > > To: "OpenSceneGraph Users" <osg-users@lists.openscenegraph.org> > > > Message-ID: > > > < [EMAIL PROTECTED]> > > > Content-Type: text/plain; charset="iso-8859-1" > > > > > > Hello Adrian > > > > > > If I get you right, you think that the OSG data representation is not > > > optimized for use within a raytracer application. So it will be > > > possible to > > > code a raytracer with OSG but results won't be very efficient and > > > powerful? > > > > > > regards, Tobias > > > > > > On 10/2/07, Adrian Egli <[EMAIL PROTECTED]> wrote: > > >> > > >> Hi Tobias, > > >> > > >> Greate would be to get a RayTracer attached to the OSG scene. With > > >> option > > >> to trace or not. Normally OSG won't trace, but if we like to get high > > >> quality screens, we can just turn on the tracing. But i was > > >> thinking about > > >> this still more then once. What we should get or what i like to > > >> integrate as > > >> soon as i have some hours to analyse the osg core, we should store > > >> the > > >> triangles, trianglesfan, ... (GL geometries) in a accelerated > > >> spatial data > > >> structure, best kd-Tree like data organisation. Even the > > >> intersection test > > >> could be boosted, also futures animations, collision checks and so > > >> on, > > >> boosting of depth sorting for transparency pre triangles should > > >> become > > >> possible. Also haptic-rendering could be an option for future > > >> application. > > >> This integration would be an essential topic. > > >> > > >> I am not yet sure how we should change the osg internal data > > >> structure, at > > >> the moment we store vertices in simple arrays. I feel like to > > >> remap them > > >> into an kd-tree. then the whole scenegraph is organised in a > > >> spatial data > > >> structure. > > >> > > >> and the once we have a fast internal data representation, we may are > > >> really close to render the scene no longer as face rendering also ray > > >> casted, ray traced parts would be an futur options. what would be > > >> really > > >> greate. May we will get small parts raytraced, others not. > > >> > > >> what are others thinking about this topic. > > >> > > >> /Adegli > > >> > > >> 2007/10/2, Tobias M?nch < [EMAIL PROTECTED]>: > > >>> > > >>> Hello to all OSG developers. > > >>> > > >>> Does anybody has developed a raytracer based on OSG or OpenGL > > >>> which is > > >>> free to use on other applications? It is important for me that no > > >>> changes > > >>> are necessary to the OSG-framework like the raytracer of Amit Ben- > > >>> David, who > > >>> modified the osg:Vec3f class. I need it for my thesis and > > >>> unfortunately I > > >>> have not enough time to code one by my own. > > >>> > > >>> best regards, Tobias > > >>> > > >>> p.s.: The source of Ben-Davids raytracer: http:// > > >>> www.cs.technion.ac.il/~cs234326/projects/GLSLRayTracer/main.htm > > <http://www.cs.technion.ac.il/%7Ecs234326/projects/GLSLRayTracer/main.htm> > > >>> > > >>> <http://www.cs.technion.ac.il/%7Ecs234326/projects/GLSLRayTracer/ > > >>> main.htm> > > >>> > > >>> _______________________________________________ > > >>> osg-users mailing list > > >>> osg-users@lists.openscenegraph.org > > >>> http://lists.openscenegraph.org/listinfo.cgi/osg-users- > > >>> openscenegraph.org > > >>> > > >>> > > >>> > > >> > > >> > > >> -- > > >> ******************************************** > > >> Adrian Egli > > >> _______________________________________________ > > >> osg-users mailing list > > >> osg-users@lists.openscenegraph.org > > >> http://lists.openscenegraph.org/listinfo.cgi/osg-users- > > >> openscenegraph.org > > >> > > >> > > > -------------- next part -------------- > > > An HTML attachment was scrubbed... > > > URL: http://lists.openscenegraph.org/pipermail/osg-users- > > > openscenegraph.org/attachments/20071002/599a86e8/attachment.html > > > > > > ------------------------------ > > > > > > _______________________________________________ > > > osg-users mailing list > > > osg-users@lists.openscenegraph.org > > > http://lists.openscenegraph.org/listinfo.cgi/osg-users- > > > openscenegraph.org > > > > > > > > > End of osg-users Digest, Vol 4, Issue 4 > > > *************************************** > > > > _______________________________________________ > > osg-users mailing list > > osg-users@lists.openscenegraph.org > > > > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > > > > > -- > ******************************************** > Adrian Egli -- ******************************************** Adrian Egli
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