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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi all<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I have added an example which simulates using VTK to render into an existing OpenGL context (with existing camera/lights, opaque objects).<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><a href="http://www.vtk.org/Wiki/VTK/Examples/Cxx/Visualization/RenderPassExistingContext">http://www.vtk.org/Wiki/VTK/Examples/Cxx/Visualization/RenderPassExistingContext</a><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Motivation:<o:p></o:p></p><p class=MsoNormal>This could be useful for projects, which have an existing rendering system, but would like to use VTK to easily render things not available in the existing rendering system, e.g. volume rendering, streamline tracing, etc. Or it might be useful if VTK is used already for data processing, but needed to be converted to local data structures to render using the existing rendering system.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Comments:<o:p></o:p></p><p class=MsoNormal>The example illustrates translucent rendering using depth peeling and volume rendering. Maybe it could be done more elegantly. If you can see how, please make any suggestions or corrections either directly on the Wiki Examples page, or send me an e-mail.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo2'><![if !supportLists]><span style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>Specifically, would it be possible to not use a VTK-based camera pass and lights pass, but instead use the pre-existing one?<o:p></o:p></p><p class=MsoListParagraph><o:p> </o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo2'><![if !supportLists]><span style='mso-list:Ignore'>2.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>If I use only a camera pass, without a lights pass, the volume rendering is dark, while the translucent actor is not. Why does this happen? It seems the volume mapper clears the existing lights…?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks<o:p></o:p></p><p class=MsoNormal>Bryn<o:p></o:p></p></div></body></html>