Preserve MIME type for unknown extensions during import

Hi @najadojo, hope you’re doing well! Here’s a suggestion from @rawnsley and Mozilla Hubs.

During GLB to GLTF conversion, it might be good to preserve the mimeType field, at least for types that are unknown to the guessFileExtension function. This would enable RGBE environment maps that Hubs has an extension for. Even if these files got a .bin extension, they would have a MIME type applied.

via https://github.com/AnalyticalGraphicsInc/gltf-vscode/issues/243

[najadojo]

@rawnsley and @emackey I’ve merged a change and published the npm package that addresses this. Here is a section of the sample gltf after conversion:

{
  "images": [
    {
      "name": "skybox",
      "uri": "hubs-scene-sample-dw0.1.0_img0.png"
    },
    {
      "name": "envmap-category",
      "mimeType": "image/vnd.radiance",
      "uri": "hubs-scene-sample-dw0.1.0_img1.bin"
    },
    {
      "name": "lightmap",
      "mimeType": "image/vnd.radiance",
      "uri": "hubs-scene-sample-dw0.1.0_img2.bin"
    },
    {
      "name": "WoodFloor040_4K_Color",
      "uri": "hubs-scene-sample-dw0.1.0_img3.ktx2"
    }
  ],
  "buffers": [
    {
      "uri": "hubs-scene-sample-dw0.1.0_data.bin",
      "byteLength": 33384
    }
  ]
}

[rawnsley]

🤯