swift-fbx

A pure-Swift FBX file parser, ported from ufbx.

• Binary FBX 7100–7700 (including 64-bit and big-endian variants) and ASCII FBX 6100–7700
• Zero dependencies (pure Swift, including DEFLATE decompression)
• Scene graph: node hierarchy with the full FBX transform chain, meshes with all vertex attributes, materials, textures, lights, cameras, bones, skinning, blend shapes
• Animation: stacks, layers, curves; keyframe interpolation and transform evaluation at arbitrary times (including pre-7000 "Takes" animation)
• Behavioral parity with ufbx, enforced by golden-dump tests against the real C implementation on 44 real-world exporter files (Maya, 3ds Max, Blender)

Usage

import SwiftFBX

let scene = try FBXScene.load(contentsOf: url)

for node in scene.nodes {
    print(node.name, node.nodeToWorld)
    if let mesh = node.mesh {
        print("  mesh:", mesh.numVertices, "vertices,", mesh.numFaces, "faces")
    }
}

// Animation
if let stack = scene.animStacks.first {
    let t = (stack.timeBegin + stack.timeEnd) / 2
    for node in scene.nodes {
        let transform = stack.anim.evaluateTransform(node: node, time: t)
        _ = transform
    }
}

// Low-level document access
let document = try FBXDocument.parse(data: data)

File and decoded-array memory work is bounded by default. Applications with a known asset budget can lower the limits; every value must be positive:

let options = FBXLoadOptions(
    maximumSourceBytes: 64 * 1_024 * 1_024,
    maximumDecodedArrayBytes: 128 * 1_024 * 1_024,
    maximumDecodedArrayElements: 16 * 1_024 * 1_024
)
let scene = try FBXScene.load(contentsOf: fileURL, options: options)

load(contentsOf:) accepts file URLs and reads only one sentinel byte beyond maximumSourceBytes, so an oversized file is rejected without being fully materialized. FBXDocument.parse(data:) applies the same source and decoded array limits to in-memory input.

Add as a Swift package

Add via URL from another package:

let package = Package(
    // ...
    dependencies: [
        .package(url: "https://github.com/jyatesdotdev/swift-fbx.git", from: "0.1.2"),
    ],
    targets: [
        .target(
            name: "MyTarget",
            dependencies: [
                .product(name: "SwiftFBX", package: "swift-fbx"),
            ]
        ),
    ]
)

In Xcode, choose File > Add Package Dependencies and paste the repository URL, then link the SwiftFBX library product to the target that imports it.

Swift Package Index

This package can be indexed and discovered on the Swift Package Index:

• Package page: https://swiftpackageindex.com/jyatesdotdev/swift-fbx
• SPI accepts package source directly from the repository URL, so publishing is done centrally on their site.

Development

• docs/DESIGN.md — architecture and porting rules
• docs/ufbx-notes/ — subsystem-by-subsystem port notes mapping ufbx.c internals
• docs/DUMP_FORMAT.md — golden dump format shared with the C reference harness
• tools/ufbx_dump.c + tools/ufbx/ — vendored ufbx reference used to (re)generate Tests/SwiftFBXTests/Resources/golden/

swift build
swift test                         # includes golden parity suite
swift run fbx-dump file.fbx        # emit the golden JSON dump for a file

License

SwiftFBX is available under the MIT License. The ufbx-derived portions retain Samuli Raivio's copyright notice, and the vendored reference retains its full license in tools/ufbx/LICENSE.