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<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>Hi all,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>When I read the VTK source code, I found some queer
codes from ln293 to ln299 in </span></font><span lang=EN-US><a
href="mk:@MSITStore:C:\Documents%20and%20Settings\ken\Desktop\VTKDoc-4.2.chm::/vtkEncodedGradientShader_8h-source.html">vtkEncodedGradientShaderh</a></span><font
size=1 face=Arial><span lang=EN-US style='font-size:9.0pt;font-family:Arial'>.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=1 face=Arial><span lang=EN-US style='font-size:
9.0pt;font-family:Arial'>I listed the codes as follows.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'> transform->MultiplyPoint( in, zero );<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'> zero[0] /= zero[3];<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'> zero[2] /= zero[3]; //it is queer
here.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'> zero[3] /= zero[3];<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'> viewDirection[0] -= zero[0];<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'> viewDirection[1] -= zero[1];<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'> viewDirection[2] -= zero[2];<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'>Shoud I change them to:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'> transform->MultiplyPoint( in, zero );<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-indent:10.0pt'><font size=2 face=Arial><span
lang=EN-US style='font-size:10.0pt;font-family:Arial'>zero[0] /= zero[3];<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'> zero[1] /= zero[3]; <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'> zero[2] /= zero[3];<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'> viewDirection[0] -= zero[0];<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'> viewDirection[1] -= zero[1];<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'> viewDirection[2] -= zero[2];<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'>Regards,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'>Ken<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-US style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
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