Rodin::MMG namespace

Key Classes

Workflow Semantics

Optimizer, Adapt, and LevelSetDiscretizer are intentionally different operations:

All workflows convert an MMG::Mesh to native MMG structures, run MMG, and convert the result back. The output is a remeshed object; input element indices should be treated as stable only where the wrapper or tests explicitly document preservation.

Auto-Dispatch

The wrappers auto-dispatch to the appropriate MMG backend based on the mesh type:

Shared Configuration (MMG5 base)

The MMG wrappers inherit common configuration methods from MMG5; each returns *this for chaining:

Required Entities

MMG::Mesh stores MMG-specific metadata:

Required vertices, edges, triangles, and tetrahedra are serialized through MEDIT, converted to native MMG MG_REQ tags, and restored from native MMG output. The optimizer and level-set wrappers restore required index sets when the original indices are still valid after remeshing. In MMG3D, setRequiredTriangle(idx) applies to boundary triangles exported to MMG's triangle table; interior faces of a tetrahedral mesh are not exported as MMG boundary triangles when face-cell incidence is available.

For level-set discretization, the tested behavior is:

• required entities not crossed by the level set retain their required metadata and original geometry in the 2D/3D cases covered by the test suite;
• required entities crossed by the level set are not guaranteed to remain intact. MMG may replace them to conform the mesh to the isovalue, even when MG_REQ, individual labels, adjacent tetrahedron labels, local closure requirements, or noSplit(ref) are used.

See MMG behavior and guarantees for the full characterization.

LevelSetDiscretizer API

In addition to MMG5 parameters, LevelSetDiscretizer provides:

noSplit(ref) is a material-reference splitting policy. It is not an element-integrity guarantee for an individual edge, triangle, or tetrahedron that the level set cuts.

MMG::Mesh cut = MMG::LevelSetDiscretizer()
  .setLevelSet(0.0)
  .split(interior, { interior, exterior })
  .setBoundaryReference(interface)
  .discretize(phi);

Use MMG::Mesh::Build() to construct meshes programmatically via the builder pattern.

Classes

class Adapt

Performs anisotropic/isotropic remeshing from a nodal size map.

class LevelSetDiscretizer

Discretizes implicit geometry defined by a nodal level-set field.

class Mesh

Local mesh enriched with MMG boundary tags and constraints.

class MeshLoader

Loads an Rodin::MMG::Mesh from the MEDIT format.

class MeshPrinter

Printer for Rodin::MMG::Mesh in MEDIT/MMG-compatible syntax.

class MMG5

Base class for MMG-backed operations in Rodin.

template<class FuncName>

class MMG5Exception

Exception type for MMG wrapper failures.

struct NoSplitT

Tag type indicating that a material reference must not be split.

class Optimizer

Improves mesh quality while preserving characteristic local sizes.

struct Split

Interior/exterior labels produced when splitting one material.

Typedefs

using SplitMap = UnorderedMap<Geometry::Attribute, std::variant<Split, NoSplitT>>

Material splitting policy map used by level-set discretization.

template<class Range>

using GridFunction = Variational::GridFunction<Variational::P1<Range, Geometry::Mesh<Context::Local>>, Math::Vector<Real>>

Grid function type used by the MMG module.

using RealGridFunction = GridFunction<Real>

Scalar MMG grid function alias.

using VectorGridFunction = GridFunction<Math::SpatialVector<Real>>

Vector-valued MMG grid function alias.

using ReturnCode = int

Return-code type used by MMG C API calls.

Functions

auto getISCDMshdistExecutable() -> const char*

Gets the configured path to the mshdist executable.

auto getISCDAdvectExecutable() -> const char*

Gets the configured path to the advect executable.

auto getMMGVerbosityLevel() -> int

Gets the MMG verbosity level selected at configuration time.

Variables

static NoSplitT NoSplit constexpr

Singleton tag instance for convenience in split configuration.

const char* ISCD_MSHDIST_EXECUTABLE constexpr

Path to the ISCD Mshdist executable.

const char* ISCD_ADVECTION_EXECUTABLE constexpr

Path to the ISCD Mshdist executable.

const int VERBOSITY_LEVEL constexpr

Verbosity level for MMG console output.

Typedef documentation

Function documentation

Variable documentation

SplitMap split;
split[5] = NoSplit;