jww-parser

JWW (Jw_cad) file parser and DXF converter for JavaScript/TypeScript.

This package uses WebAssembly to parse JWW binary files (created by Jw_cad, a popular Japanese CAD software) and convert them to DXF format.

Installation

npm install jww-parser

Usage

Node.js

import { createParser } from 'jww-parser';
import { readFileSync } from 'fs';

async function main() {
  // Create and initialize the parser
  const parser = await createParser();

  // Read a JWW file
  const jwwData = readFileSync('drawing.jww');
  const data = new Uint8Array(jwwData);

  // Parse JWW to get document structure
  const doc = parser.parse(data);
  console.log('Entities:', doc.Entities.length);
  console.log('Layers:', doc.LayerGroups.length);

  // Convert to DXF string
  const dxfString = parser.toDxfString(data);
  writeFileSync('output.dxf', dxfString);
}

main();

Browser

<!-- Include wasm_exec.js from Go -->
<script src="wasm_exec.js"></script>
<script type="module">
  import { createParser } from 'jww-parser';

  async function convertFile(file) {
    const parser = await createParser('path/to/jww-parser.wasm');

    const buffer = await file.arrayBuffer();
    const data = new Uint8Array(buffer);

    // Get DXF content
    const dxfString = parser.toDxfString(data);

    // Download as file
    const blob = new Blob([dxfString], { type: 'application/dxf' });
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url;
    a.download = file.name.replace('.jww', '.dxf');
    a.click();
  }
</script>

API

createParser(wasmPath?: string): Promise<JwwParser>

Create and initialize a JWW parser instance.

• wasmPath - Optional path to the jww-parser.wasm file

JwwParser

init(): Promise<void>

Initialize the WASM module. Called automatically by createParser().

parse(data: Uint8Array): JwwDocument

Parse a JWW file and return the document structure.

toDxf(data: Uint8Array): DxfDocument

Parse a JWW file and convert to DXF document structure (JSON).

toDxfString(data: Uint8Array): string

Parse a JWW file and convert to DXF file content string.

Types

JwwDocument

interface JwwDocument {
  Version: number;
  Memo: string;
  PaperSize: number;
  LayerGroups: LayerGroup[];
  Entities: JwwEntity[];
  Blocks: JwwBlock[];
}

JwwEntity

Supported entity types:

• JwwLine - Line segments
• JwwArc - Arcs and circles
• JwwPoint - Points
• JwwText - Text annotations
• JwwSolid - Solid fills
• JwwBlockRef - Block references

DxfDocument

interface DxfDocument {
  Layers: DxfLayer[];
  Entities: DxfEntity[];
  Blocks: DxfBlock[];
}

Requirements

• Node.js >= 18.0.0 (for Node.js usage)
• Modern browser with WebAssembly support (for browser usage)

License

AGPL-3.0