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<div class="moz-cite-prefix">Doesn't a PlaneSensor degenerate to a
(proposed) LineSensor in the case where minPosition[x|y] ==
maxPosition[x|y] (min==max for either X or Y). The spec
(<a class="moz-txt-link-freetext" href="http://www.web3d.org/documents/specifications/19775-1/V3.3/Part01/components/pointingsensor.html#PlaneSensor">http://www.web3d.org/documents/specifications/19775-1/V3.3/Part01/components/pointingsensor.html#PlaneSensor</a>)
essentially says that at the end of the 7th paragraph after the
node definition.</div>
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<div class="moz-cite-prefix">Also rotation of the parent doesn't
change the local coordinate system, just how it appears on the
display. If the parent is rotated so that the local coordinate
system has Z in one the screen primary direction (across or
up/down), then all that would be generated is a line sensor --
changes in either X or Y (the one into the display) could not be
detected.</div>
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<div class="moz-cite-prefix">Leonard Daly</div>
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<blockquote type="cite"
cite="mid:CAKdk67utSFvf4eZro4_G6J4nUudAxZsus9uQCs=2Efb=b0bPbg@mail.gmail.com">
<pre class="moz-quote-pre" wrap="">I now understand the need for LineSensor and may give it a try for
x3dom. I know freewrl has it. It may make sense to replicate it.
My initial idea would be to use the x axis of the local coordinate
system as the Line orientation. Or maybe the y axis since X3D
geometries tend to align along y (cylinder, extrusion).
Then one can construct an intersection plane which includes the x axis
and another direction at a high angle with the viewing direction to
get a clean intersection for the inital point and subsequent points
during dragging.
Is that how freewrl does it ? I think I saw that it may use an
additional field for the line orientation but it may be best to avoid
it.
Andreas
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<div class="moz-signature">-- <br>
<font class="tahoma,arial,helvetica san serif" color="#333366">
<font size="+1"><b>Leonard Daly</b></font><br>
3D Systems & Cloud Consultant<br>
LA ACM SIGGRAPH Past Chair<br>
President, Daly Realism - <i>Creating the Future</i>
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