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    Ah of course, a mask.<br>
    <br>
    Thanks that's perfect.<br>
    Cheers<br>
    A.<br>
    <br>
    On 28.10.2010 15:28, David Doria wrote:
    <blockquote
      cite="mid:AANLkTi=vO894nTCAWTWn2St9WnBVQ6whFCzshzHZY3_t@mail.gmail.com"
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      <div class="gmail_quote">On Thu, Oct 28, 2010 at 5:56 AM, Alex
        Southern <span dir="ltr">&lt;<a moz-do-not-send="true"
            href="mailto:mrapsouthern@gmail.com">mrapsouthern@gmail.com</a>&gt;</span>
        wrote:<br>
        <blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt
          0.8ex; border-left: 1px solid rgb(204, 204, 204);
          padding-left: 1ex;">Hi,<br>
          <br>
          ImageData must be rectangular, but I want certain points in
          the imageData to be transparent. I have seen the SetOpacity
          setting, &nbsp;but that affects all the ImageData.<br>
          <br>
          Can anyone tell me what my options are for this?<br>
          <br>
          Thanks<br>
          A<br>
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        </div>
        <div>This should do the trick:</div>
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          href="http://www.vtk.org/Wiki/VTK/Examples/Cxx/Images/Transparency">http://www.vtk.org/Wiki/VTK/Examples/Cxx/Images/Transparency</a><br
          clear="all">
        <br>
        <div>David&nbsp;</div>
      </div>
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