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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hi<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I have been trying to write some code, which allows me to use some of the rendering methods in VTK within an existing context, with direct calls to OpenGL done before the VTK render call.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>It seems the nice Multipass framework by François Bertel (http://cmake.org/Wiki/VTK/MultiPass_Rendering) could be used for this purpose. I tried following code (see below). However, if run an example which plots two triangles – one directly using OpenGL – one using a vtkPolyData+Mapper+Actor, then the final color of the triangles is always set by the color property of the vtkActor, even if I set a different color in the direct OpenGL code.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Does anybody have an idea what I am doing wrong here?<o:p></o:p></p><p class=MsoNormal>Is there a nice example somewhere, which uses the Multipass framework mixed with a different rendering library/OpenGL code?<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><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>void Setup()<o:p></o:p></p><p class=MsoNormal>{<o:p></o:p></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> </span><span lang=DE-CH style='font-size:9.5pt;font-family:Consolas;color:green'>// Setup renderer and render window</span><span lang=DE-CH style='font-size:9.5pt;font-family:Consolas'><o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=DE-CH style='font-size:9.5pt;font-family:Consolas'> m_Renderer = vtkRenderer::New();<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=DE-CH style='font-size:9.5pt;font-family:Consolas'><o:p> </o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> m_RenderWindow = vtkWin32OpenGLRenderWindow::New();<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> m_RenderWindow->SetWindowId(WindowId);<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> m_RenderWindow->SetParentId(ParentId);<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> m_RenderWindow->SetContextId((HGLRC)ContextId);<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> m_RenderWindow->SetDeviceContext((HDC)DeviceContext);<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> m_RenderWindow->AddRenderer(m_Renderer);<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'><o:p> </o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> vtkOpaquePass * opaquePass = vtkOpaquePass::New();<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> vtkLightsPass * lights = vtkLightsPass::New();<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'><o:p> </o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> vtkRenderPassCollection * opasses = vtkRenderPassCollection::New();<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> passes->AddItem(lights);<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> passes->AddItem(opaquePass);<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'><o:p> </o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> vtkSequencePass * seq = vtkSequencePass::New();<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> seq->SetPasses(passes);<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'><o:p> </o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> m_Renderer->SetPass(seq);<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'>}<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'><o:p> </o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'><o:p> </o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'>The callback function is:<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'><o:p> </o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'>void Callback()<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'>{<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> glPushMatrix();<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> glBegin( GL_TRIANGLES );<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> glColor3f( 1.0f, 1.0f, 1.0f ); glVertex3f( 0.2f, 1.0f, 0.0f );<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> glColor3f( 1.0f, 1.0f, 1.0f ); glVertex3f( 1.07f, -0.5f, 0.0f );<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> glColor3f( 1.0f, 1.0f, 1.0f ); glVertex3f( -0.67f, -0.5f, 0.0f );<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'> </span><span lang=DE-CH style='font-size:9.5pt;font-family:Consolas'>glEnd();<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=DE-CH style='font-size:9.5pt;font-family:Consolas'><o:p> </o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=DE-CH style='font-size:9.5pt;font-family:Consolas'> glPopMatrix();<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=DE-CH style='font-size:9.5pt;font-family:Consolas'> glPushMatrix();<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=DE-CH style='font-size:9.5pt;font-family:Consolas'> m_Renderer->Render();<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=DE-CH style='font-size:9.5pt;font-family:Consolas'> </span><span style='font-size:9.5pt;font-family:Consolas'>glPopMatrix();<o:p></o:p></span></p><p class=MsoNormal style='text-autospace:none'><span style='font-size:9.5pt;font-family:Consolas'>}<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>