Thanks for the quick reply Robert. Unfortunately I don't control the temperature models I'm working with so I'm stuck mapping the per-primitive as accurately as I can.
I was just looking through the Geometry::fixDeprecatedData() function in osg 3.2 -> am I correct in assuming that this function won't actually give me the same behavior as BIND_PER_PRIMITIVE did in previous OSG versions? As to your texture recommendation, I had considered that, I suppose I would just create a 1x1 texture for temperature value? -Ethan robertosfield wrote: > Hi Ethan, > > osg::Geometry still supports BIND_PER_VERTEX, BIND_PER_PRIMITIVE_SET and > BIND_OVERALL as these are able to map to what OpenGL supports directly. For > you work I would suggest either using BIND_PER_VERTEX or > BIND_PER_PRIMTIVE_SET, the easiest one to map to is probably > BIND_PER_PRIMITIVE_SET so you'd have one building face per osg::PrimitiveSet. > The most efficient in terms of OpenGL performance will be to duplicate the > temperature values so there is one per vertex and then use BIND_PER_VERTEX. > > > Physically I would have thought the temperature would most naturally fit to > per vertex as the edges and corners of buildings will be at the same > temperature (one point is space can't be at two temperatures) but with doing > this one need to insert extra vertices with the flat walls to allow to > accurately map the temperature variation. > > > The other route you could take is put the temperature mapping into a texture. > > > Robert. > > > > > > > > On 13 January 2014 14:12, Ethan Fahy < ()> wrote: > > > I'd like to migrate away from my current usage of BIND_PER_PRIMITIVE so > > that I can start using current versions of OSG. > > > > I have working code that does color binding on a per primitive basis. I > > believe I have a good reason to do so: I have a separate program that > > tells me what the temperature is for facets on a building. This means that > > I have one temperature value for each primitive. I can convert the 3-D > > building model that the program uses into an .ive file. I need to color > > each side of the building according to temperature, so the natural fit is > > to use BIND_PER_PRIMITIVE. > > > > The problem is that if I have a building in a single geometry object, it > > ends up having shared vertices which means I can't effectively color per > > primitive by setting all vertices the same color and coloring by vertex. > > > > The only solution I can think of is to split the single building geometry > > up so that each primitive in the building is its own geometry so that there > > are no shared vertices within the geometries and I can color each vertex by > > the color of the primitive. > > > > Am I missing anything? I tried looking in the forum archives but I was > > confused by most of the conversation about this topic. > > > > -Ethan > > > > ------------------ > > Read this topic online here: > > http://forum.openscenegraph.org/viewtopic.php?p=57865#57865 > > (http://forum.openscenegraph.org/viewtopic.php?p=57865#57865) > > > > > > > > > > > > _______________________________________________ > > osg-users mailing list > > () > > http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org > > (http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org) > > > > > ------------------ > Post generated by Mail2Forum ------------------ Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=57868#57868 _______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
