<br><br><div><span class="gmail_quote">On 2/15/06, <b class="gmail_sendername">Burlen</b> <<a href="mailto:burlen@apollo.sr.unh.edu">burlen@apollo.sr.unh.edu</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<br>It seems to me that the problem of open contours might be caused by the<br>algorithm(s) used with unstructuredGrids built with the append filter. Could<br>it have somehting to do with the fact that the boxes in my case are appended
<br>in a "willy nilly" order? adjacent boxes aren't necessarily appended one<br>after the other.<br><br></blockquote></div><br>I think this is the cause of your problem. The vtkAppendFilter does not "stitch" neighboring datasets along their boundaries, it keeps each dataset as an individual piece. So when you extract an isosurface from the combined dataset, there is no connectivity along those inter-dataset boundaries, leading to the "discontinuity" along the edges. I've run into the same issue here doing similiar things (reading a multi-block Plot3d file & using AppendDataset to only have 1 vtkDataSet to pass around).
<br><br>How to fix this? I haven't the slightest, short of writing custom code to replace vtkAppendDataset and do the stitching. You may be able to Resample the Data into a rectilinear form (use the ProbeFilter with an ImageData input), and then get the Isosurface you want, but you'll have to live with the resolution tradeoffs. It'll also be sloooooow....
<br><br clear="all"><br>-- <br>Randall Hand<br>Visualization Scientist, <br>ERDC-MSRC Vicksburg, MS<br>Homepage: <a href="http://www.yeraze.com">http://www.yeraze.com</a>