Magnum::Trade::TinyGltfImporter class

#include <MagnumPlugins/TinyGltfImporter/TinyGltfImporter.h>

• Light properties besides light type are not imported.
• Light intensity is not yet supported due to glTF extension draft state.

• The mesh3DCount() query returns a number of all primitives, not meshes
• Each multi-primitive mesh is split into a sequence of MeshData3D instances following each other
• mesh3DForName() points to the first mesh in given sequence and mesh3DName() returns the same name for all meshes in given sequence
• The object3DCount() query returns a number of all nodes extended with number of extra nodes for each additional mesh primitive
• Each node referencing a multi-primitive mesh is split into a sequence of MeshObjectData3D instances following each other; the extra nodes being a direct and immediate children of the first one with an identity transformation
• object3DForName() points to the first object containing the first primitive, object3DName() returns the same name for all objects in given sequence
• AnimationData instances returned by animation() have their AnimationData::trackTarget() values patched to account for the extra nodes, always pointing to the first object in the sequence and thus indirectly affecting transformations of the extra nodes represented as its children

• The baseColorTexture field is used for diffuse texture, if present. Otherwise, baseColorFactor is used for diffuse color, if present. Otherwise, 0xffffff_rgbf is used.
• Specular color is always 0xffffff_rgbf (never a texture)
• Shininess is always 1.0f

• The diffuseTexture field is used for diffuse texture, if present. Otherwise, diffuseFactor is used for diffuse color, if present. Otherwise, 0xffffff_rgbf is used.
• The specularGlossinessTexture field is used for a specular texture, if present (note that only the RGB channels should be used and the alpha channel — containing glossiness — should be ignored). Otherwise, specularFactor is used for specular color, if present. Otherwise, 0xffffff_rgbf is used.
• Shininess is always 1.0f

• The diffuseTexture field is used for diffuse texture, if present. Otherwise, diffuseFactor is used for diffuse color, if present. Otherwise, 0xffffff_rgbf is used.
• The specularShininessTexture field is used for specular texture, if present (note that only the RGB channels should be used and the alpha channel — containing snininess — should be ignored). Otherwise, specularFactor is used for diffuse color, if present. Otherwise, 0xffffff_rgbf is used.
• The snininessFactor field is used for snininess, if present. Otherwise 1.0f is used.

glTF leaves the defaults of sampler properties to the application, the following defaults have been chosen for this importer:

• Minification/magnification/mipmap filter: SamplerFilter::Linear, SamplerMipmap::Linear
• Wrapping (all axes): SamplerWrapping::Repeat

The importer supports the non-standard GOOGLE_texture_basis extension for referencing Basis Universal files, which then get loaded using BasisImporter (or an equivalent alias). The use is like this, equivalently to Basis own glTF example:

{
    ...
    "textures": [
        {
            "extensions": {
                "GOOGLE_texture_basis": {
                    "source": 0
                }
            }
        }
    ],
    "images": [
        {
            "mimeType": "image/x-basis",
            "uri": "texture.basis"
        }
    ],
    "extensionsUsed": [
        "GOOGLE_texture_basis"
    ],
    "extensionsRequired": [
        "GOOGLE_texture_basis"
    ]
}

The MIME type is not standard either and the importer doesn't check its value. However, in case of embedded data URIs, the prefix has to be set to data:application/octet-stream as TinyGLTF has a whitelist for data URI detection and would treat the URI as a filename otherwise:

{
    ...
    "images": [
        {
            "mimeType": "image/x-basis",
            "uri": "data:application/octet-stream;base64,..."
        }
    ]
}