[vtkusers] PDF 3D Support

[Ian Curington]

Dear Michail,

Thanks very much for your comments, they are very helpful!
As this is freshly released, we are now planning the next stage of
improvements. You are correct to point out that the quadric example is
not that nice - it was created a while ago before we built the
vtkPDF3DExporter class and needs replacing. Sorry about any confusion.
At this point it is not representative.

That's a great idea to extend the gallery to include a range of examples
covering data types; I'll work on this soon. You can see a number of
models on our current gallery - all created using the common generation
engine, but not with VTK data sources yet. We expect the quality to be
very similar to the current gallery. We've also tested pathways from VTK
to 3D PDF using VRML as intermediate step - this can work well, but
sometimes things get lost in translation and can generate very large
intermediate files - hence the vtkPDF3DExporter is far cleaner.

That's also a great idea to have some short code samples to show how VTK
examples are generated. We currently have one on the gallery - VTK
Terrain, http://www.pdf3d.co.uk/pdf/vtkterrain.pdf, I can send you the
VTK main code for this if you'd like to review. 

As for menus, PDF3D-SDK provides API control for enabling/disabling the
default Adobe Reader menu. Rather than replacing it with some other
derivative, we've taken the approach to expose an API to add interactive
buttons with dynamic control over the 3D scene. There is an example on
the gallery; "Widgets" that shows this
(http://www.pdf3d.co.uk/pdf/WidgetExample.pdf).
A custom menu system can be created using these classes.

By the way, I'd also welcome comments on how vtkPDF3DExporter could be
integrated with ParaView.

Regards, Ian

>> If I may, I'd like to comment on VTK PDF 3D support. Depending on
>> licensing and platform issues it might provide an alternate path for PDF
>> 3D output. The PDF3D-SDK has a vtkPDF3DExporter class that directly
>> captures the renderview pipeline to generate a 3D PDF file in one pass,
>> without IDTF, U3D, or pdflatex. It's currently on Win32, with Linux port
>> underway (not yet on Mac).
>> Summary: http://www.pdf3d.co.uk/pdf/PDF3D-VTK-Brief-16january08.pdf
>
>While the summary is nice and shows an improvement over VTK support in
>earlier versions of your product (the example at 
>http://www.pdf3d.jp/pdf/quadric-2a.pdf is not that nice),
>it surprisingly lacks the 3D models, only 2d shots of them.
>Please, extend the summary to an example, at least for quadric and 
>boy head, with both 3D models and VTK code for them (to see if the output 
>quality was achieved by your Exporter alone or required some precooking of 
>data).
>Some examples showing simple/elementary shapes and features are also welcome
>(like points/colored points, lines/colored lines/lines with per vertex 
>color and all that 3D Geometry, Surfaces, Textures, Labels, Actor Names 
>in Model Tree, Transparency, Vertex color shading model, Alpha-Blended 
>Textures promised in PDF3D VTK Integration Brief).
>Sorry if I ask you something that is against your corporate policy.
>
>How does the quality of PDF3DExporter output compare to results obtained 
>by exporting from VTK to some 3D format and importing that data into 
>Acrobat 3D (and/or other commercial 3D PDF making software)?
>Almost everyone in that field claims that his compresssion of U3D is 
>better than the reference implementation by Intel used in your product,
>while the newer Adobe internal format PRC seems to have both better 
>compression and additional features.
>Some of the competitors also provide their own menus, that are stated to 
>be an improvement over stock Reader ones.
>
> Sincerely, Michail