<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">
<div><br></div><div>On Jul 9, 2008, at 12:40 PM, Paul Kelly wrote:</div><div><br class="Apple-interchange-newline"><blockquote type="cite"><blockquote type="cite"><blockquote type="cite"><p style="margin: 0.0px 0.0px 0.0px 20.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">Regarding the output: <span class="Apple-converted-space"> </span>my suggestion was to output, for every cell that is</font></p> <p style="margin: 0.0px 0.0px 0.0px 20.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">visible, its<span class="Apple-converted-space"> </span>height<span class="Apple-converted-space"> </span>(or slope) *above* the line of sight;<span class="Apple-converted-space"> </span>this will give</font></p> <p style="margin: 0.0px 0.0px 0.0px 20.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">an indication of how visible the point is.<span class="Apple-converted-space"> </span>Similarly, for the cells that</font></p> <p style="margin: 0.0px 0.0px 0.0px 20.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">are *not* visible,<span class="Apple-converted-space"> </span>you could compute their height (or slope) below the line</font></p> <p style="margin: 0.0px 0.0px 0.0px 20.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">of sight.<span class="Apple-converted-space"> </span>High positive values will mean the point is very visible;<span class="Apple-converted-space"> </span>high</font></p> <p style="margin: 0.0px 0.0px 0.0px 20.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">negative values will mean the point is very un-visible.</font></p> </blockquote></blockquote><p style="margin: 0.0px 0.0px 0.0px 0.0px; font: 12.0px Helvetica; min-height: 14.0px"><br></p> <p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="3" style="font: 12.0px Helvetica">I don't quite understand what "the line of sight" is here. What I think of as the line of sight is a straight line from the observer to the visible cell, passing straight through both. Some kind of output relating to how visible the cell is definitely sounds like a very good idea though.</font></p> <p style="margin: 0.0px 0.0px 0.0px 0.0px; font: 12.0px Helvetica; min-height: 14.0px"><br></p> </blockquote></div><br><div>Sorry, I meant the height/slope above or below the horizon. In other words, at a point p, in addition to boolean visibility, we can compute</div><div>the height difference between p and the lowest point at that location that would be visible by the observer. </div><div><br></div><div><br></div><div>-Laura </div></body></html>