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Hi all,<BR>
&nbsp;<BR>
How do I make uniform transparency in a concave polygon, instead of getting multiple shades, e.g. in the attached graph?<BR>
&nbsp;<BR>
The polygon are created with:<BR>
&nbsp;<BR><FONT size=2 face=Consolas><FONT size=2 face=Consolas>
vtkPoints* points = vtkPoints::New();<BR>
vtkCellArray* cells = vtkCellArray::New();<BR>
points-&gt;SetNumberOfPoints(4);<BR>
&nbsp;<BR>
// create a concave polygon (equilateral with a cutout at the bottom)</FONT></FONT>
<P><FONT color=#008000 size=2 face=Consolas><FONT color=#008000 size=2 face=Consolas><FONT color=#008000 size=2 face=Consolas><BR></FONT></FONT></FONT><FONT size=2 face=Consolas><FONT size=2 face=Consolas>points-&gt;SetPoint(0, 10.0, 10.0, 0.0);</P>
points-&gt;SetPoint(1, 110.0, 183.2, 0.0);<BR>
points-&gt;SetPoint(2, 210.0, 10.0, 0.0);<BR>
points-&gt;SetPoint(3, 110.0, 110.0, 0.0);<BR>
cells-&gt;Allocate(1, 5);<BR>
cells-&gt;InsertNextCell(5);<BR>
cells-&gt;InsertCellPoint(0);<BR>
cells-&gt;InsertCellPoint(1);<BR>
cells-&gt;InsertCellPoint(2);<BR>
cells-&gt;InsertCellPoint(3);<BR>
cells-&gt;InsertCellPoint(0);<BR>
vtkPolyData* poly = vtkPolyData::New();<BR>
poly-&gt;Initialize();<BR>
poly-&gt;SetGlobalWarningDisplay(1);<BR>
poly-&gt;SetPoints(points);<BR>
poly-&gt;SetPolys(cells);<BR></FONT></FONT>
&nbsp;<BR>
A vtkActor2D and a vtkPolyDataMapper2D was used for the rendering.<BR>
<BR>Many thanks!<BR>Xiaofeng<BR><BR><BR>                                               <br /><hr />The New Busy think 9 to 5 is a cute idea. Combine multiple calendars with Hotmail.  <a href='http://www.windowslive.com/campaign/thenewbusy?tile=multicalendar&ocid=PID28326::T:WLMTAGL:ON:WL:en-US:WM_HMP:042010_5' target='_new'>Get busy.</a></body>
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