Gltf builder

The spec file GltfBuilder.spec.ts contains examples of usage.

Writing points

Use a points builder to build the points structure. Then build it using the GltfBuilder

const gltfBuilder = new GltfBuilder()
const verticesCount = vertices.length
const pointsBuilder = new PointsBuilder(verticesCount, scale)
pointsBuilder.addVertices(vertices)
pointsBuilder.buildGltf(gltfBuilder)
const gltf = gltfBuilder.build()
console.log(JSON.stringify(gltf))

Writing lines

Use a line builder to build the line structure. Then build it using the GltfBuilder

const gltfBuilder = new GltfBuilder()
const verticesCount = vertices.length
const indexesCount = vertices.length
const lineBuilder = new LinesBuilder(verticesCount, indexesCount, scale, LineType.LINE_STRIP)
vertices.forEach(vertex => {
    const index = lineBuilder.addVertex(vertex)
    lineBuilder.addIndex(index)
})
lineBuilder.buildGltf(gltfBuilder)
const gltf = gltfBuilder.build()
console.log(JSON.stringify(gltf))

Writing triangles

Use a triangles builder to build the line structure. Then build it using the GltfBuilder

const gltfBuilder = new GltfBuilder()
const verticesCount = simple3DObject.vertices.length
const indicesCount = simple3DObject.indices.length
const normalsCount = simple3DObject.normals.length
const trianglesBuilder = new TrianglesBuilder(verticesCount, indicesCount, normalsCount, scale, TriangleType.TRIANGLES)
simple3DObject.vertices.forEach(vertex => trianglesBuilder.addVertex(vertex))
simple3DObject.normals.forEach(normal => trianglesBuilder.addNormal(normal))
simple3DObject.indices.forEach(index => trianglesBuilder.addIndex(index))
trianglesBuilder.buildGltf(gltfBuilder)
const gltf = gltfBuilder.build()
console.log(JSON.stringify(gltf))

Writing Gltf to file

The Gltf can be written to file by stringifying the JSON object

const gltfBuilder = new GltfBuilder()
// add contents
const gltf = gltfBuilder.build()
fs.writeFileSync(path, JSON.stringify(gltf));

Gltf files can be viewed with https://gltf-viewer.donmccurdy.com/