Node-level visualization support for coefficients of Subcell limiting

src/callbacks_step/save_solution_dg.jl

@@ -125,8 +125,6 @@ function save_solution_file(u, time, dt, timestep,
         n_vars = size(data, 1)
     end
 
-    # TODO: In trixi2txt, the data file is read; including node_variables for every mesh.
-    # So, do we need node_variables here as well?
     if HDF5.has_parallel()
         save_solution_file_parallel(data, time, dt, timestep, n_vars, mesh, equations,
                                     dg, cache, solution_variables, filename,

src/solvers/dgsem_tree/subcell_limiters.jl

@@ -104,7 +104,6 @@ end
 function get_node_variables!(node_variables, limiter::SubcellLimiterIDP,
                              ::VolumeIntegralSubcellLimiting, equations)
     node_variables[:alpha_limiter] = limiter.cache.subcell_limiter_coefficients.alpha
-    # Note: The coefficients are uninitialized in the first solution file.
     return nothing
 end
 end # @muladd

src/time_integration/methods_SSP.jl

@@ -237,5 +237,7 @@ function Base.resize!(semi, volume_integral::VolumeIntegralSubcellLimiting, new_
     # Resize container subcell_limiter_coefficients
     @unpack limiter = volume_integral
     resize!(limiter.cache.subcell_limiter_coefficients, new_size)
+    (; alpha) = limiter.cache.subcell_limiter_coefficients
+    alpha .= zero(eltype(alpha))
 end
 end # @muladd