If your terrain surface uses a GLSL fragment shader, you could add a 2D point in polygon test on the x/y coordinate and add or blend a highlighting color to the generated fragment when it passes the PIP test. It might get kind of slow when your enclosing polygons has a lot of vertices.
For a decent PIP test algorithm, look here: http://stackoverflow.com/questions/11716268/point-in-polygon-algorithm 2015-11-18 12:58 GMT+01:00 Sebastian Messerschmidt < sebastian.messerschm...@gmx.de>: > Hello Bean? > > You can use the polytop intersector to get all primitives inside and draw > them with an polygon offset applied on top of the original geometry. > > Cheers > Sebastian > > primitive problem > > <https://groups.google.com/forum/#%21searchin/osg-users/how$20to$20draw$20a$20Curved$20Surface$20on$20the$20top$20of$20terrain$3F/osg-users/q0fcYqNZ84E/LqfRH3rBrTUJ> > > > <https://groups.google.com/forum/#%21searchin/osg-users/how$20to$20draw$20a$20Curved$20Surface$20on$20the$20top$20of$20terrain$3F/osg-users/q0fcYqNZ84E/LqfRH3rBrTUJ> > > > 1、how to draw a Curved Surface on the top of terrain? like the fig. > 2、 how to compute the surface area of the Curved Surface? > [image: 内嵌图片 1] > I want to use polytope intersector, but I don't have inspiration. So > can you give me some advise? > thank you a lot. > > > _______________________________________________ > osg-users mailing > listosg-users@lists.openscenegraph.orghttp://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 > >
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