How to Convert 3D Models in TypeScript

Aspose.3D FOSS for TypeScript converts between 3D formats by loading into a neutral Scene representation and saving to the target format. This guide shows the most common conversions.

Step-by-Step Guide

npm install @aspose/3d

import { Scene } from '@aspose/3d';
import { ObjLoadOptions } from '@aspose/3d/formats/obj';

const scene = new Scene();
const opts = new ObjLoadOptions();
opts.enableMaterials = true;
scene.open('model.obj', opts);

// OBJ → glTF binary (GLB)
scene.save('output.glb');

// OBJ → STL
scene.save('output.stl');

// OBJ → COLLADA
scene.save('output.dae');

import { Scene } from '@aspose/3d';
import { ObjLoadOptions } from '@aspose/3d/formats/obj';

const scene = new Scene();
scene.open('model.obj', new ObjLoadOptions());
scene.save('model.glb');
console.log('Converted OBJ → GLB');

import { Scene } from '@aspose/3d';

const scene = new Scene();
scene.open('model.glb');
scene.save('model.stl');
console.log('Converted GLB → STL');

import { Scene } from '@aspose/3d';

const scene = new Scene();
scene.open('model.dae');
scene.save('model.3mf');
console.log('Converted COLLADA → 3MF');

import * as fs from 'fs';
import * as path from 'path';
import { Scene } from '@aspose/3d';
import { ObjLoadOptions } from '@aspose/3d/formats/obj';

const inputDir = './input';
const outputDir = './output';

fs.mkdirSync(outputDir, { recursive: true });

const objFiles = fs.readdirSync(inputDir).filter(f => f.endsWith('.obj'));

for (const file of objFiles) {
    const inputPath = path.join(inputDir, file);
    const outputFile = file.replace('.obj', '.glb');
    const outputPath = path.join(outputDir, outputFile);

    const scene = new Scene();
    scene.open(inputPath, new ObjLoadOptions());
    scene.save(outputPath);

    console.log(`Converted ${file} → ${outputFile}`);
}

Supported Conversion Matrix

FBX is not supported via the high-level open()/save() API — the format is not wired into auto-detection. All FBX cells above are ✗.

Common Issues and Fixes

Materials are lost after conversion

OBJ materials (usemtl, .mtl file) are loaded when ObjLoadOptions.enableMaterials = true. When saving to glTF, PBR material properties are mapped automatically. Complex materials (procedural, multi-layer) may convert with reduced fidelity.

Mesh appears scaled incorrectly

Different formats use different default units (millimeters for STL, meters for glTF). Use ObjLoadOptions.scale when loading or StlSaveOptions.scale when saving to normalize units.

Coordinate system mismatch (model flipped or rotated)

Some formats use right-hand Y-up, others Z-up. Use ObjLoadOptions.flipCoordinateSystem = true or apply a rotation to the root node after loading.

Frequently Asked Questions

Does conversion preserve animations?

Animation data is preserved when converting between formats that support it (e.g., COLLADA → glTF). STL and OBJ do not carry animation data. FBX is not supported via scene.open()/scene.save(), so FBX animation round-trips are not available through the high-level API.

Is texture data preserved?

Textures referenced by OBJ materials or embedded in glTF are carried through to the scene graph. When saving to GLB (binaryMode = true), the binary buffer is embedded in a single file. For OBJ output, textures are saved as separate files alongside the .obj.

Can I convert many files in parallel?

scene.open() and scene.save() are synchronous. Use Node.js worker_threads for parallel processing.

See Also

• How to Load 3D Models in TypeScript
• How to Save 3D Models in TypeScript
• Format Support
• API Reference