gltf

A Go package for simple, efficient, and robust serialization/deserialization of glTF 2.0 (GL Transmission Format), a royalty-free specification for the efficient transmission and loading of 3D scenes and models by applications.

Features

• High parsing speed and moderate memory consumption.
• glTF specification v2.0.0
  • ASCII glTF.
  • Binary glTF(GLB).
  • PBR material description.
• glTF validaton
  • Validate against schemas.
  • Validate coherence.
• Buffers
  • Parse BASE64 encoded embedded buffer data(DataURI).
  • Load .bin file.
• Read from io.Reader
  • Boilerplate for disk loading.
  • Custom callback handlers.
  • Automatic ASCII / glTF detection.
• Write to io.Writer
  • Boilerplate for disk saving.
  • Custom callback handlers.
  • ASCII / Binary
• Extensions
  • KHR_draco_mesh_compression
  • KHR_lights_punctual
  • KHR_materials_pbrSpecularGlossiness
  • KHR_materials_unlit
  • KHR_techniques_webgl
  • KHR_texture_transform

Perfomance

All the functionality is benchmarked and tested using the official glTF Samples in the utility package qmuntal/gltf-bench. The results show that the perfomance of this package is equivalent to fx-gltf, a reference perfomance-driven glTF implementation for C++, .

Examples

Read

doc, err := gltf.Open("./a.gltf")
if err != nil {
  panic(err)
}
fmt.Print(doc.Asset)

Save

The following example generates a 3D box with colors per vertex.

package main

import (
    "github.com/qmuntal/gltf"
)

func main() {
    doc := &gltf.Document{
        Accessors: []gltf.Accessor{
            {BufferView: gltf.Index(0), ComponentType: gltf.UnsignedShort, Count: 36, Type: gltf.Scalar},
            {BufferView: gltf.Index(1), ComponentType: gltf.Float, Count: 24, Max: []float64{0.5, 0.5, 0.5}, Min: []float64{-0.5, -0.            -0.5}, Type: gltf.Vec3},
            {BufferView: gltf.Index(2), ComponentType: gltf.Float, Count: 24, Type: gltf.Vec3},
            {BufferView: gltf.Index(3), ComponentType: gltf.Float, Count: 24, Type: gltf.Vec4},
            {BufferView: gltf.Index(4), ComponentType: gltf.Float, Count: 24, Type: gltf.Vec2},
        },
        Asset: gltf.Asset{Version: "2.0", Generator: "FBX2glTF"},
        BufferViews: []gltf.BufferView{
            {Buffer: 0, ByteLength: 72, ByteOffset: 0, Target: gltf.ElementArrayBuffer},
            {Buffer: 0, ByteLength: 288, ByteOffset: 72, Target: gltf.ArrayBuffer},
            {Buffer: 0, ByteLength: 288, ByteOffset: 360, Target: gltf.ArrayBuffer},
            {Buffer: 0, ByteLength: 384, ByteOffset: 648, Target: gltf.ArrayBuffer},
            {Buffer: 0, ByteLength: 192, ByteOffset: 1032, Target: gltf.ArrayBuffer},
        },
        Buffers: []gltf.Buffer{{ByteLength: 1224, URI: bufferData}},
        Materials: []gltf.Material{{
            Name: "Default", AlphaMode: gltf.Opaque, AlphaCutoff: gltf.Float64(0.5),
            PBRMetallicRoughness: &gltf.PBRMetallicRoughness{BaseColorFactor: &gltf.RGBA{R: 0.8, G: 0.8, B: 0.8, A: 1}, MetallicFactor: gltf.Float64(0.1), RoughnessFactor: gltf.Float64(0.99)},
        }},
        Meshes: []gltf.Mesh{{Name: "Cube", Primitives: []gltf.Primitive{{Indices: gltf.Index(0), Material: gltf.Index(0), Mode: gltf.Triangles, Attributes: map[string]uint32{"POSITION": 1, "COLOR_0": 3, "NORMAL": 2, "TEXCOORD_0": 4}}}}},
        Nodes: []gltf.Node{
            {Name: "RootNode", Children: []uint32{1, 2, 3}},
            {Name: "Mesh"},
            {Name: "Cube", Mesh: gltf.Index(0)},
            {Name: "Texture Group"},
        },
        Samplers: []gltf.Sampler{{WrapS: gltf.Repeat, WrapT: gltf.Repeat}},
        Scene:    gltf.Index(0),
        Scenes:   []gltf.Scene{{Name: "Root Scene", Nodes: []uint32{0}}},
    }
    if err := gltf.Save(doc, "./cube.gltf"); err != nil {
        panic(err)
    }
}

const bufferData = "data:application/octet-stream;base64,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"