Surface Mesh

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Surface mesh export can write either the top visible surface or all material interfaces. Material IDs are stored in the mesh point data under the "MaterialIds" label.

Overview

Use the domain member function saveSurfaceMesh or getSurfaceMesh to export the triangulated surface of a geometry.
The function can output either:

• the topmost surface (default), or
• all material interfaces when addInterfaces is enabled.

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API

Get the surface mesh

SmartPointer<viennals::Mesh<NumericType>>
getSurfaceMesh(bool addInterfaces = false,
               bool sharpCorners = false,
               double minNodeDistanceFactor = 0.01) const;

• addInterfaces — include all internal material interfaces (not only top surface).
• sharpCorners — preserve sharp features during meshing.
• minNodeDistanceFactor — minimum node distance factor used when addInterfaces is enabled.

Save the surface mesh

void saveSurfaceMesh(const std::string &fileName,
                     bool addInterfaces = true,
                     bool sharpCorners = false,
                     double minNodeDistanceFactor = 0.01) const;

Writes the resulting triangulated mesh to a .vtp file including optional material and metadata information.

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Example usage

C++

auto domain = ps::Domain<double, 3>::New();
// ... create geometry in domain ...

// Save top-level surface only
domain->saveSurfaceMesh("surface.vtp", false);

// Save all material interfaces
domain->saveSurfaceMesh("interfaces.vtp", true);

// Save all interfaces and preserve sharp corners
domain->saveSurfaceMesh("interfaces_sharp.vtp", true, true);

Python

import viennaps as vps

domain = vps.Domain()
# ... create geometry in domain ...

# Save top surface only
domain.saveSurfaceMesh("surface.vtp", False)

# Save all material interfaces
domain.saveSurfaceMesh("interfaces.vtp", True)

# Save all interfaces and preserve sharp corners
domain.saveSurfaceMesh("interfaces_sharp.vtp", True, True)

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Returned mesh

When using getSurfaceMesh(), the returned object is a viennals::Mesh that can be further processed or visualized:

auto mesh = domain->getSurfaceMesh(true);
viennals::VTKWriter<double> writer(mesh, "mesh.vtp");
writer.apply();

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Behavior summary

Option	Description	Default
addInterfaces	Export all material interfaces instead of only the top surface	true for saveSurfaceMesh, false for getSurfaceMesh
sharpCorners	Preserve sharp features during meshing	false
minNodeDistanceFactor	Minimum node distance factor for multi-surface interface meshing	0.01

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Notes

• All exported meshes are in VTK (.vtp) format.
• The mesh includes material IDs and metadata when a MaterialMap is present in the domain.
• Use getSurfaceMesh() for programmatic access or saveSurfaceMesh() for direct file output.