//Change blending to maximum per component instead of weighted sum
vtkOpenGLRenderWindow *renwin = dynamic_cast<vtkOpenGLRenderWindow*>(ren->GetRenderWindow());
vtkOpenGLExtensionManager *extensions = renwin->GetExtensionManager();
//Change blending to maximum per component instead of weighted sum
vtkOpenGLRenderWindow *renwin = dynamic_cast<vtkOpenGLRenderWindow*>(ren->GetRenderWindow());
vtkOpenGLExtensionManager *extensions = renwin->GetExtensionManager();