Chapter8: Expand "Unstructured Topology" section with vtkPolyhedron details

[mwestphal]

• Clarify unstructured data storage by breaking down points, connectivity, and types.
• Add explanation of vtkPolyhedron-specific structures: faces and face locations.
• Update complexity discussion to highlight the impact of polyhedron representation.
• Include new figure (Figure 8-34b) to illustrate complete unstructured data with polyhedron support.
• Adjust terminology to improve clarity and consistency across descriptions.

[mwestphal]

Here is a replacement for Figure8-35.png:

Here is a new image to upload: Figure8-34b.png

[mwestphal]

@jcfr please review and merge if possible

[mwestphal]

@jcfr ping

[jcfr]

@mwestphal Once you confirm the preview (https://vtk-book--18.org.readthedocs.build/en/18/VTKBook/08Chapter8.html) looks good, we will integrate with the following commit message:

Chapter8: Expand "Unstructured Topology" section with vtkPolyhedron details

- Clarify unstructured data storage by breaking down points, connectivity, and types.
- Add explanation of vtkPolyhedron-specific structures: faces and face locations.
- Update complexity discussion to highlight the impact of polyhedron representation.
- Include new figure (Figure 8-34b) to illustrate complete unstructured data with polyhedron support.
- Adjust terminology to improve clarity and consistency across descriptions.

[jcfr]

For future reference, how did you generate the new and updated figures ?

[mwestphal]

For future reference, how did you generate the new and updated figures ?

I used draw.io, I still have the original files if needed.

[mwestphal]

@mwestphal Once you confirm the preview (https://vtk-book--18.org.readthedocs.build/en/18/VTKBook/08Chapter8.html) looks good, we will integrate with the following commit message:

Chapter8: Expand "Unstructured Topology" section with vtkPolyhedron details

- Clarify unstructured data storage by breaking down points, connectivity, and types.
- Add explanation of vtkPolyhedron-specific structures: faces and face locations.
- Update complexity discussion to highlight the impact of polyhedron representation.
- Include new figure (Figure 8-34b) to illustrate complete unstructured data with polyhedron support.
- Adjust terminology to improve clarity and consistency across descriptions.

LGTM :)

[jcfr]

I still have the original files if needed.

Which format are those ? We could also upload them as resource at https://github.com/Kitware/vtk-book/releases/tag/book-resources

[danlipsa]

@mwestphal It would be nice to show in the new figure that fact that Offsets has m+1 entries, where m is the number of cells. That is, the last entry in the Offsets points to one after the last entry in the Connectivity array.
https://vtk.org/doc/nightly/html/classvtkCellArray.html#details

[mwestphal]

I still have the original files if needed.

Which format are those ? We could also upload them as resource at https://github.com/Kitware/vtk-book/releases/tag/book-resources

https://drive.google.com/file/d/1C_2XBwrTPLR1unhS0spwu90F_znTAwvz/view?usp=drive_link

https://drive.google.com/file/d/1SgtBE5GzGSp5_HSq4jMZLrXsxQHG6Bt1/view?usp=sharing

Its a propritary format afaics.

[mwestphal]

@mwestphal It would be nice to show in the new figure that fact that Offsets has m+1 entries, where m is the number of cells. That is, the last entry in the Offsets points to one after the last entry in the Connectivity array. https://vtk.org/doc/nightly/html/classvtkCellArray.html#details

This is already shown.

[danlipsa]

@mwestphal It would be nice to show in the new figure that fact that Offsets has m+1 entries, where m is the number of cells. That is, the last entry in the Offsets points to one after the last entry in the Connectivity array. https://vtk.org/doc/nightly/html/classvtkCellArray.html#details

This is already shown.

where is that? Is it the mCells and kFaces squares? It is not obvious that these are entries and where do they point to? One could think they simply state the number of entries (0 to m-1).

[mwestphal]

Is it the mCells and kFaces squares?

Yes

It is not obvious that these are entries and where do they point to?

They point nowhere

Feel free to improve the diagram, links are available above if you want to give it a try.

[danlipsa]

They point nowhere

That is the problem! They should point to the end of the Connectivity list.

Feel free to improve the diagram, links are available above if you want to give it a try.

I'll give it a try.