From a868f185b04c7f6e4529361a005804abbc6b0074 Mon Sep 17 00:00:00 2001
From: Niklas Neher <73897120+LasNikas@users.noreply.github.com>
Date: Mon, 6 Nov 2023 09:50:51 +0100
Subject: [PATCH] Add option in `SolutionSavingCallback` to write meta data
 (#247)

* option `write_meta_data` for API

* add to docs
---
 src/callbacks/solution_saving.jl | 15 ++++++++++-----
 src/visualization/write2vtk.jl   |  8 +++++---
 2 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/src/callbacks/solution_saving.jl b/src/callbacks/solution_saving.jl
index 9d290d46d..2846556d8 100644
--- a/src/callbacks/solution_saving.jl
+++ b/src/callbacks/solution_saving.jl
@@ -26,6 +26,7 @@ To ignore a custom quantity for a specific system, return `nothing`.
 - `append_timestamp=false`:     Append current timestamp to the output directory.
 - 'prefix':                     Prefix added to the filename.
 - `custom_quantities...`:       Additional user-defined quantities.
+- `write_meta_data`:            Write meta data.
 - `verbose=false`:              Print to standard IO when a file is written.
 
 # Examples
@@ -52,6 +53,7 @@ struct SolutionSavingCallback{I, CQ}
     interval              :: I
     save_initial_solution :: Bool
     save_final_solution   :: Bool
+    write_meta_data       :: Bool
     verbose               :: Bool
     output_directory      :: String
     prefix                :: String
@@ -63,7 +65,7 @@ function SolutionSavingCallback(; interval::Integer=0, dt=0.0,
                                 save_initial_solution=true,
                                 save_final_solution=true,
                                 output_directory="out", append_timestamp=false,
-                                prefix="", verbose=false,
+                                prefix="", verbose=false, write_meta_data=true,
                                 custom_quantities...)
     if dt > 0 && interval > 0
         throw(ArgumentError("Setting both interval and dt is not supported!"))
@@ -79,8 +81,8 @@ function SolutionSavingCallback(; interval::Integer=0, dt=0.0,
 
     solution_callback = SolutionSavingCallback(interval,
                                                save_initial_solution, save_final_solution,
-                                               verbose, output_directory, prefix,
-                                               custom_quantities, [-1])
+                                               write_meta_data, verbose, output_directory,
+                                               prefix, custom_quantities, [-1])
 
     if dt > 0
         # Add a `tstop` every `dt`, and save the final solution.
@@ -134,7 +136,8 @@ end
 
 # affect!
 function (solution_callback::SolutionSavingCallback)(integrator)
-    (; interval, output_directory, custom_quantities, verbose, prefix, latest_saved_iter) = solution_callback
+    (; interval, output_directory, custom_quantities, write_meta_data,
+    verbose, prefix, latest_saved_iter) = solution_callback
 
     vu_ode = integrator.u
     semi = integrator.p
@@ -157,7 +160,9 @@ function (solution_callback::SolutionSavingCallback)(integrator)
 
     @trixi_timeit timer() "save solution" trixi2vtk(vu_ode, semi, integrator.t; iter=iter,
                                                     output_directory=output_directory,
-                                                    prefix=prefix, custom_quantities...)
+                                                    prefix=prefix,
+                                                    write_meta_data=write_meta_data,
+                                                    custom_quantities...)
 
     # Tell OrdinaryDiffEq that u has not been modified
     u_modified!(integrator, false)
diff --git a/src/visualization/write2vtk.jl b/src/visualization/write2vtk.jl
index 8bedd5642..88e640956 100644
--- a/src/visualization/write2vtk.jl
+++ b/src/visualization/write2vtk.jl
@@ -1,5 +1,6 @@
 """
-    trixi2vtk(vu_ode, semi, t; iter=nothing, output_directory="out", prefix="", custom_quantities...)
+    trixi2vtk(vu_ode, semi, t; iter=nothing, output_directory="out", prefix="",
+              write_meta_data=true, custom_quantities...)
 
 Convert Trixi simulation data to VTK format.
 
@@ -12,6 +13,7 @@ Convert Trixi simulation data to VTK format.
 - `iter`:                 Iteration number when multiple iterations are to be stored in separate files.
 - `output_directory`:     Output directory path. Defaults to `"out"`.
 - `prefix`:               Prefix for output files. Defaults to an empty string.
+- `write_meta_data`:      Write meta data.
 - `custom_quantities...`: Additional custom quantities to include in the VTK output. TODO.
 
 
@@ -22,7 +24,7 @@ trixi2vtk(sol[end], semi, 0.0, iter=1, output_directory="output", prefix="soluti
 TODO: example for custom_quantities
 """
 function trixi2vtk(vu_ode, semi, t; iter=nothing, output_directory="out", prefix="",
-                   custom_quantities...)
+                   write_meta_data=true, custom_quantities...)
     (; systems, neighborhood_searches) = semi
     v_ode, u_ode = vu_ode.x
 
@@ -41,7 +43,7 @@ function trixi2vtk(vu_ode, semi, t; iter=nothing, output_directory="out", prefix
         trixi2vtk(v, u, t, system, periodic_box;
                   output_directory=output_directory,
                   system_name=filenames[system_index], iter=iter, prefix=prefix,
-                  custom_quantities...)
+                  write_meta_data=write_meta_data, custom_quantities...)
     end
 end