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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>I am attempting to test viewsheds from multiple heights below the roofline of particular buildings. I have been identifying viewing positions from directly from LiDAR data, but I cannot find a way to use absolute values for elevation. The build-in visibility analysis seems to always use the raster elevation value plus the relative observer height. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I would like to use an absolute Z value, and have some immediate zone that is ignored (i.e., ignore the first 2m of obstructions) so that a viewpoint that might be lower than the raster elevation value can get outside of a building. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Is there a plugin or alternative visibility analysis tool that can do this? I was able to get it to work in Manifold Viewer, but I would like to keep the workflow within QGIS if possible. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thank you, Chris<o:p></o:p></p></div></body></html>