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<div class="moz-cite-prefix">On 9/22/20 4:03 PM, wrote:<br>
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Dear Dr. Pounds:</div>
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Can you explain the special case (noted in the slides) with
regards to polygon tessellation in more detail? In particular,
how are we supposed to know which angles to check? (I imagine
the special case applies to more shapes than just the shape
shown in the slide.)</div>
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<p>So you are referring to pages 83-85 of the slides. In step 2 of
the tessselation process (page 69) you are supposed to check to
see if the line segment intersects any of the line segments in
your remaining list of vertices. If if doesn't then you should be
cleared to draw the line back to the initial vertex where you
started. In this case my triangle would be V0-V1-V2. However,
this would be incorrect in the special case. If the angle to the
next vetex in the list (angle V1-V2-V3) is less than the V1-V2-V0
angle then you can't draw the line back. You have to move to the
next vertex in the list (V1) and start the process over.</p>
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<pre class="moz-signature" cols="72">--
Andrew J. Pounds, Ph.D. (<a class="moz-txt-link-abbreviated" href="mailto:pounds_aj@mercer.edu">pounds_aj@mercer.edu</a>)
Professor of Chemistry and Computer Science
Director of the Computational Science Program
Mercer University, Macon, GA 31207 (478) 301-5627
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