Talk:Selection

Wylie: [Regarding OpenGL Selection] These cons seem to be fairly small. Having a good solution for point and rectangle selection seems to be enough. My recollection is that the fixed sized buffer isn't really an issue.... that you can indicate to opengl to give you the first 1 or 5 or N(all) matching selections, and only in the last case is it an issue. The polygon/edge/point issue seems like it might be a factor in all the approaches... you may be able to render those primatives separately if that type of functionality is a high priority.

Just a quick note: Selection in VTK is not limited to picking. See vtkSelectVisiblePoints and VTK/Rendering/Testing/Tcl/labeledMesh.tcl. Not really efficient but it has been in VTK for a long time.

Berk 16:44, 11 Jan 2006 (EST)

Updated the discussion to reflect this, many thanks Tshead 13:36, 12 Jan 2006 (EST)

In VTK, edges are not separate entities and cannot be easily extracted. In order to support edge selection, proper support for edges would have to be added. As far as I know, this is not in the list of things to do of any VTK project. VTK did not implement edges because it ends up making the data structures very fat. Also, editing a mesh in place (as in CAD) is very difficult in VTK. I think that we should stay away from CAD like functionality until we are ready to tackle another big architectural change in VTK. Berk 09:28, 17 Jan 2006 (EST)