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<DIV><FONT face=MingLiu size=2>Dear all VTK user:</FONT></DIV>
<DIV><FONT face=²Ó©úÅé size=2>I want to update the position of the object by the 
encoder signal and show the path of the object move!&nbsp; I try to 
renWin-&gt;EraseOff but it doesn't work!&nbsp; But I find that function was work 
in ..\cowwalk.tcl.&nbsp; I try to use the user interface to change the cow 
position, and the image of the cows will keep on the screen.&nbsp; 
Why...?</FONT></DIV>
<DIV><FONT face=²Ó©úÅé size=2>My code was something like that:--------</FONT></DIV>
<DIV><FONT face=MingLiu size=2></FONT>&nbsp;</DIV>
<DIV><FONT face=MingLiu size=2>for ( i = 1; i &lt; 2000; i++)</FONT></DIV>
<DIV><FONT face=MingLiu 
size=2>&nbsp;{&nbsp;<BR>&nbsp;ren1-&gt;AddActor(joinActor);<BR>&nbsp;ren1-&gt;AddActor(cutterActor);<BR>&nbsp;ren1-&gt;SetBackground(0.1,0.2,0.4);<BR>&nbsp;renWin-&gt;SetSize(500,500);<BR>&nbsp;renWin-&gt;Render();</FONT></DIV>
<DIV><FONT face=MingLiu size=2></FONT>&nbsp;</DIV>
<DIV><FONT face=MingLiu size=2>&nbsp;//print out the input<BR>&nbsp;cout 
&lt;&lt; "please enter x, y, z" &lt;&lt;"\n";<BR>&nbsp;cin 
&gt;&gt;x&gt;&gt;y&gt;&gt;z;<BR>&nbsp;a=x+a;<BR>&nbsp;b=y+b;<BR>&nbsp;c=z+c;</DIV>
<DIV>&nbsp;</DIV>
<DIV>&nbsp;cutterActor-&gt;SetPosition(a, b 
,c);<BR>&nbsp;ren1-&gt;AddActor(cutterActor);<BR>&nbsp;renWin-&gt;Render();<BR>&nbsp;renWin-&gt;Render();<BR>&nbsp;renWin-&gt;EraseOff;</DIV>
<DIV>&nbsp;</DIV>
<DIV>&nbsp;<BR>&nbsp;}</DIV>
<DIV>-------------------------</DIV>
<DIV>the for loop just simulate the encoder signal input!</DIV>
<DIV>&nbsp;</DIV>
<DIV><FONT face=MingLiu>Please help!&nbsp; </FONT></DIV>
<DIV>Thanks for any advise!</DIV>
<DIV>&nbsp;</DIV>
<DIV>Best regards,</DIV>
<DIV>German Leung&nbsp;</FONT></DIV></BODY></HTML>