libcascadeModule shape
Runtime values, type-only named imports, filesystem ownership, and memory access.
The root entry's default export is an initialised instance. All OCCT runtime values live on it, and each one is also a named value export of the same module.
import oc, { type TopoDS_Shape } from 'libcascade';
using box = new oc.BRepPrimAPI_MakeBox(10, 10, 10);
const shape: TopoDS_Shape = box.Shape();Named imports resolve to real values as well as types, so
import { BRepPrimAPI_MakeBox } from 'libcascade' and oc.BRepPrimAPI_MakeBox
are the same binding.
Bound classes and namespaces
Classes are direct instance properties. OCCT namespaces such as TopoDS,
Interface_Static, and XCAFDoc_DocumentTool are static-method objects:
oc.Interface_Static.SetIVal('write.step.schema', 5);
const edge = oc.TopoDS.Edge(genericShape);Filesystem (oc.FS)
Use the Emscripten virtual filesystem for OCCT file readers and writers:
const path = '/result.step';
writer.Write(path);
const bytes = oc.FS.readFile(path) as Uint8Array;
oc.FS.unlink(path);
return bytes;FS.readFile() returns an owned Uint8Array; its bytes remain valid after
the file is unlinked. Copy only when your own API needs an independent buffer.
| Method | Purpose |
|---|---|
FS.readFile(path) | Read owned bytes |
FS.writeFile(path, bytes) | Write an input file |
FS.unlink(path) | Remove a virtual path |
FS.mkdir(path) | Create a directory |
FS.readdir(path) | List a directory |
Linear memory (oc.wasmMemory)
Advanced pointer interop uses typed arrays created from the live
WebAssembly.Memory buffer:
const bytes = new Uint8Array(oc.wasmMemory.buffer);
const values = new Float64Array(oc.wasmMemory.buffer);A call that allocates may grow memory and detach an existing view. Create a
fresh typed array from oc.wasmMemory.buffer after such calls. Most consumers
never need direct memory access.
Exception helpers
Exception helpers are also instance properties. See Exception classes and Debugging WASM exceptions.
Module re-init
Calling createInstance() from libcascade/init creates another WASM instance with a separate C++ heap.
Memoise it when an application should share one runtime.