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<DIV><FONT size=2 face=Arial>Hi,</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>I am trying to draw a black rubber band
using</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>
pixels[... ] = 0</FONT></DIV>
<DIV><FONT size=2 face=Arial> pixels[... + 1] = 0</FONT></DIV>
<DIV><FONT size=2 face=Arial> pixels[... + 2] = 0</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>and</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial> SetRGBACharPixelData( ...,
pixels, 0 )</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>(taken from <FONT
size=2>vtkInteractorStyleRubberBandPick). </FONT></FONT><FONT size=2
face=Arial>This works apart from the background, where no band is shown. If the
transparency is set to 1</FONT></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>
<DIV><FONT size=2 face=Arial> pixels[... + 3] = 1</FONT></DIV>
<DIV> </DIV>
<DIV>the band is drawn on the background but it is not erased when new pixel
data is set, only on rendering.</DIV>
<DIV> </DIV>
<DIV>SetPixelData( ..., pixels, 0 ) doesn't have the same problem but appears
slower.</DIV>
<DIV> </DIV>
<DIV>Any help would be much appreciated.</DIV>
<DIV> </DIV>
<DIV>Thanks,</DIV>
<DIV> </DIV>
<DIV>John.</DIV></DIV></FONT></BODY></HTML>