VTK supports 3d render windows as well as 2d render windows and 2d actors/mappers to visualize<br>image data. So you are able to use several 2d actors to create layer based visualizations.<br><br><a href="http://www.vtk.org/doc/nightly/html/classvtkActor2D.html">http://www.vtk.org/doc/nightly/html/classvtkActor2D.html</a><br>
<br>If we are able to bring raster, volume and vector into VTK, we will be able to use the hundreds of<br>VTK classes (image, volume and vector) to process grass data. <br><br><a href="http://www.vtk.org/doc/nightly/html/classes.html">http://www.vtk.org/doc/nightly/html/classes.html</a><br>
<br>Which IMHO will bring us enormous benefit in form of parallel image processing and<br>complex image-vector, vector-vector and vector-volume algorithms.<br> <br>Just my 2c<br>Soeren<br><br><div><span class="gmail_quote">2008/2/25, <a href="mailto:benjamin.ducke@ufg.uni-kiel.de">benjamin.ducke@ufg.uni-kiel.de</a> <<a href="mailto:benjamin.ducke@ufg.uni-kiel.de">benjamin.ducke@ufg.uni-kiel.de</a>>:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
><br> > why not to use the python bindings of VTK (<a href="http://www.vtk.org">http://www.vtk.org</a>) to do 3D<br> > rendering? It seems to me that VTK is a bit easier to handle than OpenGL<br> > directly, but my programming skills are not the best.<br>
> WolfgangZ<br> <br> <br>Apart from the problem with limited coordinate ranges brought about by<br> OpenGL, VTK uses a visualization pipeline rather than layers. There is<br> nothing wrong with this per se, but GIS users are accustomed to layers<br>
that cover each other in a pre-defined order, even if there is no<br> difference in the Z coordinates. VTK projects all objects into the same<br> 3D space, potentially giving unexpected results, e.g. when overlaying<br> vector outlines on a raster surface without raising the former a little<br>
bit towards the zenith.<br> <br> Might be worth thinking about this. I don't know how easy or complicated<br> it would be to emulate a layer-based drawing on a VTK rendering<br> pipeline.<br> <br> Benjamin<br> <br><br>
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