Why another glTF2 library?

1. I want to learn Odin because I like philosophy behind it and syntax. I also tried Zig for few weeks, but it's syntax is not compelling to me.
2. I don't like cgltf implementation in vendor:cgltf and it doesn't work on *Nix based systems (for now), only on Windows.
3. Odin has built-in many great native packages like core/encoding/json so why not write glTF file format package that uses Odin types and remove C hint fields from cgltf wrapper?
4. Learning how to implement specification document into working code. In this case it's glTF2
5. Because it's fun.

Progress

:heavy_check_mark: - fully implemented :heavy_plus_sign: - partially implemented :x: - not implemented

| Type | Status | Details | Specification URL | |---|---|---|---| | Accessors | :heavy_check_mark: | | https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#reference-accessor | | Animations | :heavy_check_mark: | | https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#reference-animation | | Asset | :heavy_check_mark: | | https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#reference-asset | | Buffers | :heavy_check_mark: | | https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#reference-buffer | | Buffer Views | :heavy_check_mark: | | https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#reference-bufferview | | Cameras | :heavy_check_mark: | | https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#reference-camera | | Images | :heavy_check_mark: | | https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#reference-image | | Materials | :heavy_check_mark: | | https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#reference-material | | Meshes | :heavy_plus_sign: | Missing mesh primitive targets | https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#reference-mesh | | Nodes | :heavy_check_mark: | | https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#reference-node | | Samplers | :heavy_check_mark: | | https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#reference-sampler | | Scene | :heavy_check_mark: | It's just an integer | | | Scenes | :heavy_check_mark: | | https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#reference-scene | | Skins | :heavy_check_mark: | | https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#reference-skin | | Textures | :heavy_check_mark: | | https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#reference-texture | | Extensions | :heavy_check_mark: | Represented as JSON.Value | https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#reference-extension | | Extensions Used | :heavy_check_mark: | Array of strings | | | Extensions Required | :heavy_check_mark: | Array of strings | | | Extras | :heavy_check_mark: | Represented as JSON.Value | https://registry.khronos.org/glTF/specs/2.0/glTF-2.0.html#reference-extras |

How to use it

1. Download glTF2 package from github and put in your source folder.
2. Load entire glTF2 file into memory (simplest way).
3. You can change floating point precision (by default it's 32bit) to 64bit, by setting flag to Odin compiler like this: -define:GLTF_DOUBLE_PRECISION=true

import "gltf2"

main :: proc() {
    // This procedure sets file format from file extension [gltf/glb]
    data, error := gltf2.load_from_file("file_name.[gltf/glb]")
    switch err in error {
    case gltf2.JSON_Error: // handle json parsing errors
    case gltf2.GLTF_Error: // handle gltf2 parsing errors
    }
    // if there are no errors we want to free memory when we are done with processing gltf/glb file.
    defer gltf2.unload(data)

    // do stuff with 'data'
    // ...

    // Iterate over buffer elements using accessor:
    buf := gltf2.buffer_slice(data, 0).([][3]f32)
    for val, i in buf {
        fmt.printf("Index: %v = %v\n", i, val)
    }
}

3. Load parts of file into memory and parse itself. It can be handy if you can't load entire file into memory.

import "gltf2"

main :: proc () {
    // Set options for gltf2 parser.
    // is_glb must be set to true if file is in binary format. Most likely it will have "*.glb" suffix. By default it's gltf or JSON file format.
    // delete_content set to true will delete bytes provided in procedure call. This is what 'load_from_file' does.
    options := gltf2.Options{ is_glb = [true/false(default)], delete_content = [true/false(default)] }

    // Load some part of file that is valid JSON object
    data, error := gltf2.parse(bytes, options)
    switch err in error {
    case gltf2.JSON_Error: // Handle JSON parsing errors
    case gltf2.GLTF_Error: // Handle GLTF2 parsing errors
    }
    // If there are no errors we want to free memory when we are done with processing gltf/glb file.
    defer gltf2.unload(data)
}

How You can help.

1. Implement missing functionality (package is still missing some stuff).
2. Remove bugs (they are for sure).
3. Optimize code.