Hi Felix, instead of using explicit 3D shapes, you could also use view-aligned quads with a semi-transparent gauss-texture. These textures could be pre-generated, I think the fountain example in OSG might also be helpful with this. They could also be created on demand in shaders, based on their Gauss attributes. We use a similar trick to draw lots of nicely shaded particles with ellipsoidal or spherical appearance, in this case for flow visualization and molecular visualization, e.g. see http://graphics.tudelft.nl/Projects/AtmosphericViz (this was OpenGL) and the first two images on http://graphics.tudelft.nl/VRVis (these are OSG). If you're interested I can probably get some source code your way, but I'd have to check with colleagues first.
cheers, Gerwin On Wed, Aug 18, 2010 at 11:19 AM, Felix Engelmann <efe+...@tu-chemnitz.eu> wrote: > Hi, > I need to visualize points in 3D, whose positions are Gauss distributed. The > expected values and the standard deviations for each x, y and z coordinate > are given. So, how can I do that with OSG? > I could draw a sphere (using osg::SphereDrawable) with a fixed radius at the > center and another transparent sphere around it for visualizing the standard > deviation. But that doesn't look nice... > What I'm looking for is some kind of 3D-radial gradient. The transparency > should increase along the gradient accourding to the Gaussian distribution > function. > Note, that the standard deviation can be different for each dimension. > I'm a newbie in OSG and not an OpenGL expert. Some example code would be > really helpful. > > Thank you > > Sincerely, > Felix > > ------------------ > Read this topic online here: > http://forum.openscenegraph.org/viewtopic.php?p=30872#30872 > > > > > > _______________________________________________ > osg-users mailing list > osg-users@lists.openscenegraph.org > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > _______________________________________________ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
