Hi Claudio,
is it possibile with osgUtil::IntersectionVisitor, know what is
intersected polygon (example the number 2 or the named "ad32") and which
texture is mapped to this polygon?(the name of file which contains the
texture)
See the documentation of osgUtil::LineSegmentIntersector::Intersection.
(which you get from the LineSegmentIntersector which you gave to the
IntersectionVisitor)
http://www.openscenegraph.org/documentation/OpenSceneGraphReferenceDocs/a01467.html
In the Public Attributes:
* nodePath is the path to the node that was hit for this intersection
* drawable is the drawable that was hit (osg::Geometry or whatever)
* primitiveIndex is the index of the primitive that was hit, so if
drawable is an osg::Geometry which has one primitiveSet in mode
GL_TRIANGLES, primitiveIndex would be the triangle index that was hit
(formed of vertices 3*primitiveIndex, 3*primitiveIndex+1 and
3*primitiveIndex+2 in the geometry's vertex array). How to get the
primitive/vertices independently of primitive set mode, I don't know,
you'll have to work that out yourself. There must be some code in OSG
that does this already, check the osgpick example or look around in the
OSG sources.
* To get the texture, just traverse the nodePath and get the last
texture once you get to drawable (checking the nodes' statesets). You
can't get the texture filename like that, but perhaps you can have a map
of filename to texture* in your app and make the correspondence that way.
(the rest is speculation, someone please correct me if I'm wrong)
I think ratioList is the barycentric coordinates of where the hit
occurred on the polygon (i.e. if it was a triangle that was hit, there
will be 3 ratios in ratioList, which you can then use to find out where
in the triangle the hit occurred by multiplying the 3 vertices of the
triangle by the 3 ratios) but I'm not sure. If that's the case, you can
do the same with the triangle's texture coordinates at the 3 same
vertices and thus get where in the texture the hit occured.
In general, you should get acquainted with the doxygen-generated
reference documentation, and be prepared to navigate through the pages
in it to find out how to "connect" things together and where to get the
information you need.
Hope this helps,
J-S
--
______________________________________________________
Jean-Sebastien Guay [EMAIL PROTECTED]
http://www.cm-labs.com/
http://whitestar02.webhop.org/
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