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<body class='hmmessage'>hi,<BR>when I compiled an example of vtkImageShiftScale with VTK and C++ , I found a small problem . the example is ImageInteractor .and my problem is : at first time , I can draw a rectangle on a CT picture with mouse , and when I press the mouse left button again ,a rectangle could be drawn again but the CT picture disappear . and I have make the picture to be visibility when I press the left mouse button : <BR> pictureActor->VisibilityOn();<BR>and when I release the left mouse button I set it to be invisibility :<BR> pictureActor->VisibilityOff();<BR>but unfortunately , I could not see the CT picture after I draw a rectangle . So what is wrong with my program ? and how should I do to work out it ? thank you ! <BR><br /><hr />不登录就能管理多个邮件帐户，试试 Windows Live Mail。 <a href='http://get.live.com/betas/maildesktop_betas' target='_new'>立即尝试！</a></body>
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