Improvement: Mesh handle tutorials by Vyp3er · Pull Request #2348 · DLR-AMR/t8code

Vyp3er · 2026-06-22T08:40:12Z

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General

The reviewer executed the new code features at least once and checked the results manually.
The code follows the t8code coding guidelines.
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codecov · 2026-07-01T09:48:30Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.36%. Comparing base (c7d150a) to head (a0c918c).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2348   +/-   ##
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  Coverage   82.36%   82.36%           
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  Files         125      125           
  Lines       20708    20708           
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  Hits        17056    17056           
  Misses       3652     3652

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lenaploetzke

Partial review. Thank you for your work, this is really nice and my comments are mainly documentation! :)

Co-authored-by: lenaploetzke <70579874+lenaploetzke@users.noreply.github.com>

lenaploetzke

Review adapt callback file

lenaploetzke · 2026-07-21T11:04:14Z

Could you please have a look at the failing workflows?
Please also make sure in the future to try your code once before committing.

lenaploetzke

Most things are just typos and capitalization.

Co-authored-by: lenaploetzke <70579874+lenaploetzke@users.noreply.github.com>

lenaploetzke · 2026-08-14T08:59:15Z

+    auto mesh = build_mesh<mesh_type> (comm, uniform_level);
+    /* Write the mesh to a vtu file. */
+    t8_global_productionf (" [t8 step 3 Mesh handle] \n");
+    t8_global_productionf (" [t8 step 3 Mesh handle] Writing adapted mesh to vtu file: step3_adapted_mesh.vtu\n");


Would be better to introduce a variable for the name and reusing it! That way if you change the name, you do not have to change it everywhere :)

lenaploetzke · 2026-09-07T12:11:38Z

+    t8_global_productionf (" [mesh_step3] Writing adapted mesh to vtu file: step3_adapted_mesh.vtu\n");
+    t8_global_productionf (" [mesh_step3] \n");
+    t8_mesh_handle::write_mesh_to_vtk (*mesh, "step3_adapted_mesh.vtu");


Please introduce a variable file_name or something like this for the vtu file name

lenaploetzke · 2026-09-11T11:47:08Z

+#include "t8_mesh_tutorials_common.hxx"         /** Adaption function definition used for this tutorial. */
+#include <memory>
+
+/** Build our adapted mesh by transferring the adaption parameters and adapting once with our adapt_callback_sphere function.


Suggested change

/** Build our adapted mesh by transferring the adaption parameters and adapting once with our adapt_callback_sphere function.

/** Build our adapted mesh by transferring the adaption parameters and adapting once with the adapt_callback_sphere function defined in \ref t8_mesh_tutorials_common.hxx.

lenaploetzke · 2026-09-11T11:50:00Z

+ * according to our own criterion.
+ *
+ * The geometry (coarse mesh) is again a cube, this time modelled with
+ * 6 tetrahedra, 6 prisms and 4 cubes.


Suggested change

* 6 tetrahedra, 6 prisms and 4 cubes.

* 6 tetrahedra, 6 prisms and 4 hexahedra.

I know cube is also used in the forest tutorial but we do not use "cube" for elements in general.

lenaploetzke · 2026-09-11T11:50:13Z

+std::unique_ptr<TMeshClass>
+build_mesh (sc_MPI_Comm comm, int level)
+{
+  /* Generate a hybrid hypercube, made out of cubes, prisms etc. */


Suggested change

/* Generate a hybrid hypercube, made out of cubes, prisms etc. */

/* Generate a hybrid hypercube, made out of hexahedra, prisms etc. */

lenaploetzke · 2026-09-11T11:54:09Z

+build_mesh (sc_MPI_Comm comm, int level)
+{
+  /* Generate a hybrid hypercube, made out of cubes, prisms etc. */
+  auto mesh = t8_mesh_handle::handle_hypercube_hybrid_uniform_default<TMeshClass> (level, comm);


Do you think it is clearer if we also build the mesh in the main just as in the forest step 3 tutorial? And have the function only for adaption? Maybe it is clearer to isolate only the part that is new for this tutorial.

lenaploetzke · 2026-09-11T11:58:51Z

+ *  \param mesh  The initial mesh to adapt.
+*/
+void
+create_partitioned_balanced_mesh (const std::unique_ptr<mesh_type>& mesh)


Same as for adapt: we do not create a mesh here, we partition & balance an existing mesh

lenaploetzke · 2026-09-11T11:59:07Z

+ *  \param mesh  The initial mesh to adapt.
+*/
+void
+create_ghost_mesh (const std::unique_ptr<mesh_type>& mesh)


lenaploetzke · 2026-09-11T11:59:36Z

+void
+create_ghost_mesh (const std::unique_ptr<mesh_type>& mesh)
+{
+  /* Creating the ghost layers. */


Suggested change

/* Creating the ghost layers. */

/* Set flag such that ghost layer is created on commit. */

lenaploetzke · 2026-09-11T12:01:09Z

+                                           true, false, false);
+
+    /**
+     * GHOST MESH


Suggested change

* GHOST MESH

* GHOST LAYER

lenaploetzke · 2026-09-11T12:02:31Z

+#include <mesh_handle/mesh_io.hxx>              /** Used to export mesh to vtk files. */
+#include <mesh_handle/concepts.hxx> /** Include this to use c++ concepts related to the mesh handle. This can be used to constraint the template parameters to only allow mesh handle classes. */
+#include <t8_types/t8_vec.hxx>      /** t8 vector dataclass. */
+#include "t8_mesh_tutorials_common.hxx" /** Default adaption function. */


Suggested change

#include "t8_mesh_tutorials_common.hxx" /** Default adaption function. */

#include "t8_mesh_tutorials_common.hxx" /** Adaption function definition used for this tutorial. */

Schmitt added 5 commits June 19, 2026 09:37

First Changes and File Creation

05c741b

Spellchecking correct

53199cb

Mesh_handle_tutorial Step3

665d24c

Mesh_handle_tutorial Step3

9523fc5

Mesh_handle_tutorial Step3 fixed and Step4 added.

604e003

Vyp3er changed the title ~~Mesh handle tutorials~~ Improvement: Mesh handle tutorials Jul 1, 2026

added bsd license

282f592

Vyp3er marked this pull request as ready for review July 1, 2026 08:46

Merge remote-tracking branch 'origin/main' into mesh_handle_tutorials

9f7696b

lenaploetzke self-requested a review July 1, 2026 08:52

lenaploetzke self-assigned this Jul 1, 2026

spell checking corrected

bd84430

lenaploetzke reviewed Jul 16, 2026

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Vyp3er and others added 5 commits July 17, 2026 09:45

Merge branch 'main' into mesh_handle_tutorials

ff4aa99

Apply suggestion from @lenaploetzke

d0dc470

Co-authored-by: lenaploetzke <70579874+lenaploetzke@users.noreply.github.com>

Documentation Changes and Renaming

ca472bd

added documentation and comments

9896011

Added Scope into main to prevent deletion Error

a05095c

lenaploetzke reviewed Jul 20, 2026

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Integrated Review and cleaned up the comments.

bfe57f8

lenaploetzke reviewed Jul 20, 2026

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Schmitt added 2 commits July 20, 2026 16:40

Adapted to comments.

b79b1d6

renamed element data tutorial to step 5

7b316f3

lenaploetzke reviewed Jul 21, 2026

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lenaploetzke assigned Vyp3er and unassigned lenaploetzke Jul 22, 2026

Fixed Pull Requested changes

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Vyp3er assigned lenaploetzke Aug 6, 2026

lenaploetzke requested changes Aug 6, 2026

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lenaploetzke removed their assignment Aug 6, 2026

Vyp3er and others added 2 commits August 10, 2026 13:43

Apply suggestions from code review

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Co-authored-by: lenaploetzke <70579874+lenaploetzke@users.noreply.github.com>

Fixed errors marked in pull request

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Vyp3er assigned lenaploetzke and unassigned Vyp3er Aug 10, 2026

change print labels

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lenaploetzke reviewed Aug 14, 2026

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lenaploetzke assigned Vyp3er and unassigned lenaploetzke Aug 14, 2026

Schmitt added 2 commits August 23, 2026 10:14

Merge main and resolve conflicts

d47f0f5

Fixing comments

a06cc2d

Vyp3er assigned lenaploetzke and unassigned Vyp3er Aug 23, 2026

Schmitt added 4 commits August 23, 2026 11:41

Fixed Doxygen errorrs

8500924

Fixed Doxygen errors

c800745

Doxygen errors

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Doxygen errors

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lenaploetzke reviewed Sep 11, 2026

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lenaploetzke assigned Vyp3er and unassigned lenaploetzke Sep 11, 2026

	/** Build our adapted mesh by transferring the adaption parameters and adapting once with our adapt_callback_sphere function.
	/** Build our adapted mesh by transferring the adaption parameters and adapting once with the adapt_callback_sphere function defined in \ref t8_mesh_tutorials_common.hxx.

	* 6 tetrahedra, 6 prisms and 4 cubes.
	* 6 tetrahedra, 6 prisms and 4 hexahedra.

	/* Generate a hybrid hypercube, made out of cubes, prisms etc. */
	/* Generate a hybrid hypercube, made out of hexahedra, prisms etc. */

	/* Creating the ghost layers. */
	/* Set flag such that ghost layer is created on commit. */

	#include "t8_mesh_tutorials_common.hxx" /** Default adaption function. */
	#include "t8_mesh_tutorials_common.hxx" /** Adaption function definition used for this tutorial. */

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Vyp3er commented Jun 22, 2026 •

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