Module simmesh 

Simulation results (FEA/CFD) for the 3D preview – pure Rust, no ParaView.

Readers for the open result formats most solvers can write:

• legacy VTK (.vtk): ASCII and BINARY (big endian), DATASET UNSTRUCTURED_GRID and POLYDATA, the classic CELLS layout and the OFFSETS/CONNECTIVITY layout of file version 5;
• VTK XML UnstructuredGrid (.vtu) and PolyData (.vtp): ascii, inline binary (base64) and appended data (raw or base64), optional zlib compression, UInt32/UInt64 headers, every integer and float type;
• CalculiX results (.frd, ASCII): nodes (2C), elements (3C) and the nodal result blocks (-4 DISP, -4 STRESS, …).

Every reader fills one Grid (points, cells, point and cell data); Grid::into_mesh turns it into the preview Mesh: volume cells (tetrahedra, hexahedra, wedges, pyramids – quadratic ones by their corner nodes) contribute only their outer faces (faces used by exactly one cell), surface cells are drawn as they are, and interior points are dropped.

Result values become scalar Fields on the vertices: one-component data as is, six- or nine-component tensors as von Mises equivalent, other vectors as magnitude. Cell data is averaged to the points. At most MAX_FIELDS fields are kept – the viewer offers them in a selector.

Like the mesh readers, everything is defensive: counts are limited and checked against the data before anything is allocated, decompression is bounded by the sizes the arrays need, indices are checked – a hostile file is an error, never a panic, an endless loop or an unbounded allocation.

Constants

MAX_CELLS

Cells (elements) of one result file.

MAX_CONNECTIVITY

Node references of all cells together.

MAX_NODES

Points of one result file.

MAX_RESULT_TRIANGLES

Surfaces with more triangles are thinned out evenly (gaps are visible, the viewer stays fast).

Functions

frd

CalculiX result files (.frd, ASCII). Nodes, elements and every nodal result block are read; a block that occurs several times (one per increment) shows its last increment.

vtk_legacy

Legacy .vtk files (UNSTRUCTURED_GRID and POLYDATA).

vtk_xml

VTK XML UnstructuredGrid (.vtu) and PolyData (.vtp) files.