Re: [osg-users] Near-uniform tessellation of a concave polygon for heightmaps
mp3butcher wrote: > Hi > I think nobody respond because there multiple path for it > Your problem can be split in two: > 1)tesselation > 2)real (not screen space) displacement mapping > > 1)Tesselation > -osgUtil::Tesselator > -Tesselation Shader > > 2)Real Displacement mapping > For this step You must be sure of your level of understanding of OpenGL(and > osg) because you'll have to use transformfeedback > Todo so you'll have to draw your vertices as points, displace them according > your heightmap texture (in VS) and store them in a buffer for future use (in > GS) > (The Transformfeedback spec says theres no garanty that indices remain the > same but in practice i never saw mess in GS output sequence) > > Cheers > > > > > Kanpachi wrote: > > I am given the contour/boundary of a concave polygon which cannot have > > holes, and I need to apply a heightmap to it. To this end, I need to > > perform a near-uniform tessellation of the polygon to generate a mesh. > > > > A picture would be worth a thousand words here, but alas, I don't have 2 > > posts yet. :P > > > > How can I perform this tessellation? Ideally, the solution could > > parameterize the 'resolution' of the vertices to adjust the detail of the > > mesh. > > > > If this is somehow possible using OSG's built-in tessellation library that > > would be ideal, but I'm open to introducing an additional (hopefully > > lightweight) dependency if necessary. > > > > Thanks! > -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=70812#70812 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Near-uniform tessellation of a concave polygon for heightmaps
Hi I think nobody respond because there multiple path for it Your problem can be split in two: 1)tesselation 2)real (not screen space) displacement mapping 1)Tesselation -osgUtil::Tesselator -Tesselation Shader 2)Real Displacement mapping For this step You must be sure of your level of understanding of OpenGL(and osg) because you'll have to use transformfeedback Todo so you'll have to draw your vertices as points, displace them according your heightmap texture (in VS) and store them is a buffer for future use (in GS) (The Transformfeedback spec says theres no garanty to indices stay the same but in practice i never saw mess in GS ouput sequence) Cheers Kanpachi wrote: > I am given the contour/boundary of a concave polygon which cannot have holes, > and I need to apply a heightmap to it. To this end, I need to perform a > near-uniform tessellation of the polygon to generate a mesh. > > A picture would be worth a thousand words here, but alas, I don't have 2 > posts yet. :P > > How can I perform this tessellation? Ideally, the solution could parameterize > the 'resolution' of the vertices to adjust the detail of the mesh. > > If this is somehow possible using OSG's built-in tessellation library that > would be ideal, but I'm open to introducing an additional (hopefully > lightweight) dependency if necessary. > > Thanks! -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=70808#70808 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Near-uniform tessellation of a concave polygon for heightmaps
This didn't attract much interest, but for posterity, I achieved results I am fairly happy with using the difficult-to-Google Triangle library by a fellow named Jonathan Shewchuk. I'd post a direct link but I'm still not allowed :) -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=70792#70792 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
