Hi, See the compactdisc.osg and compactdisc-texcoord.osg examples in osgtoy (http://osgtoy.cvs.sourceforge.net/osgtoy/osgtoy/osgtoy-data/) They differ only in how they send the tangent vectors: the former uses a generic GLSL attribute, the latter sends the tangent in a built-in texcoord.
(ATI drivers have (had?) a bug such that any use of generic attributes caused all geometry to vanish! Hence the need for the built-in attribute variation) cheers -- mew Emmanuel Roche wrote: > Okay, in this case, is someone aware of a solution to access those > attributes in GLSL anyway through their index ? I guess I'm not the > first one trying to use attributes no lol ? > > > I think there is one solution at least (and that's the one I'm going to > use if I find nothing better...) : I could use to built in attribute > variables ( gl_Color, gl_SecondaryColor, gl_MultiTexCoord0 to 7)... > which can be assigned with OSG functions (setColorArray, etc...). But I > really think this is not a good final solution... > > > regards, > > Emmanuel. > > > 2007/4/11, Robert Osfield <[EMAIL PROTECTED] > <mailto:[EMAIL PROTECTED]>>: > > Hi Emmanuel, > > The OSG doesn't presently support naming of vertex attributes, only > use of indexes. > > Naming of vertex attributes is a bit of awkward issue as the way the > naming is set up in OpenGL prevents one from display listing geometry, > and display listing of geometry is what the OSG does by default for > performance reasons. This area is a bit of an oddity in OpenGL. > > Robert. > > On 4/11/07, Emmanuel Roche <[EMAIL PROTECTED] > <mailto:[EMAIL PROTECTED]>> wrote: > > Hello !! > > > > I'm trying to generate the tangent,binormal,normal base for a GLSL > parallax > > shader. I would need to provide the "tangent" and "binormal" > vectors as > > "attribute" (in GLSL grammar)... I checked OSG source : apparently > I need to > > use the TangentSpaceGenerator class to build the arrays, but then, in > > osg::Geometry I can only use setVertexAttribArray(unsigned int > index,Array* > > array) I guess, so the array would be associated to an index > number and not > > a "name", could someone explain me how to do the following step > (link this > > index number to the wanted name I guess...) ? > > > > thanks in advance :-) > > > > regards, > > Emmanuel. -- Mike Weiblen -- Austin Texas USA -- http://mew.cx/ _______________________________________________ osg-users mailing list [email protected] http://openscenegraph.net/mailman/listinfo/osg-users http://www.openscenegraph.org/
