Support layering through RenderPasses

[alvarosan]

@johnkit @aashish24 , here is the current version, let me know what you think. As it is, both examples work. In the end I decided to keep a vector of actors per vtkGeoMapLayerPass to avoid having to traverse the global array from vtkRenderer. I will try it out with DataBrowser and if things go well with selection I will move on and finish up the layer-manipulation API in vtkMap.

[alvarosan]

One thing to bear in mind is that by keeping a separate vector of vtkProps per render pass actor culling and visibility (already handled by vtkRenderer) might also need to be checked per render pass. Because of this, I am starting to lean towards looping through the global (already filtered by vtkRenderer regarding culling and visibility) list. Not a major change at this point so I will probably try this tomorrow. Thoughts @johnkit @aashish24 ?

[johnkit]

Let's discuss this afternoon.

• I still definitely want to include culling somewhere in the process.
• And if traversing the prop list each pass is an easy way to do that, let's go for it.

[alvarosan]

@johnkit @aashish24 , this version is in very good shape in case you want to have a look at the implementation. Seems to integrate seamlessly in DataBrowser (selection working and showing a simpler rubber band). I will solve the conflicts next.

[aashish24]

Roger that @alvarosan @johnkit I will get the reviews our by Monday

[johnkit]

Hey @alvarosan Is there a file missing? A couple places #include a vtkMap_typedef.h file, but I don't seem to have that when I checkout out your branch.

[alvarosan]

I added that file, probably missed to check it in, sorry for that.

[alvarosan]

Done @johnkit

[johnkit]

In order to build on OSX, I had to explicitly include OpenGL link libraries, because of the call to glDisable(GL_DEPTH_TEST). Are you OK adding this patch (or something equivalent) to the CMakeLists.txt file: diff.txt

[alvarosan]

Sure, I can add the patch.

[alvarosan]

@johnkit , added CMakeLists.txt patch to include OpenGL.

[johnkit]

Thanks. Let's go ahead and merge this.

When I run the examples on my OSX build, however, VTK is getting an opengl error, apparently every time it draws. I'll paste below. It's not clear that the rendering passes are at issue, so let's see if this also occurs on other machines.

ERROR: In /Users/john/kitware/es/git/vtk/Rendering/OpenGL2/vtkOpenGLGlyph3DHelper.cxx, line 588
vtkOpenGLGlyph3DHelper (0x7ff0ac850a00): failed after Render 1 OpenGL errors detected
  0 : (1282) Invalid operation

[alvarosan]

@johnkit , could you run DataBrowser using this branch, I would like to know if the issue persists. I could not reproduce it on linux but I will try on bigmac. The error is caught here, but 'Invalid operation' can happen by many reasons so I need to narrow it down to the exact gl call that triggers it. Seems unlikely to be related to render passes though, but it's worth checking.