vcti-fileloader-slim

Fileloader plugin for CST SLIM (.slm/.slim) mesh files.

Overview

vcti-fileloader-slim reads the SLIM mesh files written by CST Studio Suite (3d.slm, .slim) into a mesh-schema DataNode subtree. SLIM is a PLY-derived binary format; SlimLoader (built on vcti-fileloader-mesh) parses it directly in pure numpy — no CST DLL — and reads the edgeless hex 3d.slm files that CST's own SlimMeshReader rejects. Every fixed-width element (node, edge, triangle, tetrahedron, ...) becomes one lazy structured-array block whose shape and record dtype come from the header, so a mesh is browsable without reading a byte of body; block reads are zero-copy views into the file buffer. Point rows keep file order, so a point's row index is its SLIM node index — the global_index CST result readers use.

Installation

pip install vcti-fileloader-slim

In requirements.txt

vcti-fileloader-slim>=1.0.0

In pyproject.toml dependencies

dependencies = [
    "vcti-fileloader-slim>=1.0.0",
]

Quick Start

from pathlib import Path
from vcti.fileloader.core import DataNode
from vcti.fileloader.slim import SlimLoader
from vcti.tree.core import DictTree

loader = SlimLoader()
tree = DictTree(root_data=DataNode())

with loader.open(Path("3d.slm")) as handle:
    mesh_root = loader.populate(handle, tree, tree.root_handle)
    # blocks are lazy — materialise what you touch, inside the open()
    for h in tree.children(mesh_root):
        p = tree.payload(h)
        print(p.name, p.shape, p.dtype)      # header facts, nothing read

The subtree conforms to the mesh schema, so its accessors apply directly:

from vcti.mesh.schema import connectivity, coordinates, load_mesh_blocks

with loader.open(Path("3d.slm")) as handle:
    mesh_root = loader.populate(handle, tree, tree.root_handle)
    blocks = load_mesh_blocks(tree, mesh_root)   # materialises the blocks

xyz = coordinates(blocks["node"])                # (N, 3) float64
tri = connectivity(blocks["triangle"])           # (M, 3) int64
uid = blocks["node"]["uid"]                      # per-node id, row-aligned

Register it like any fileloader plugin:

from vcti.fileloader.slim import get_loader_descriptor

registry.register(get_loader_descriptor())       # id: slim-numpy-loader

For header inspection without touching the body:

from vcti.fileloader.slim import parse_header

header = parse_header(Path("3d.slm").read_bytes())
[(e.name, e.count) for e in header.elements]     # element inventory

What it reads

See docs/slim-format.md for the format reference and docs/design.md for the design.

Dependencies

• vcti-fileloader-mesh — mesh loader base and schema (brings vcti-fileloader and vcti-mesh-schema).
• numpy — header-driven structured-array decoding.