You can't render concave polygons like that. Internally, GL_POLYGON is used to render them and that doesn't work for concave polygons. You'll need to tesselate them. Use vtkPolygon::Triangulate to do a ear cut triangulation and if that fails, use vtkDelaunay2D after generating sample points inside the loop.<div>
<br></div><div>--</div><div>karthik</div><div><br></div><div><div class="gmail_quote">On Sun, Nov 20, 2011 at 10:14 AM, mandalin <span dir="ltr"><<a href="mailto:mandalin147@gmail.com">mandalin147@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">Greetings !<br>
<br>
When I render concave polygons, a black flickering region seems to fill a<br>
portion of the concave area that should be empty.<br>
<br>
I see this complaint on older posts, has this been resolved ? I would prefer<br>
not running them through a triangle filter, is there another option?<br>
<br>
Thanks in advance,<br>
Amanda<br>
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