AnySceneImporter: recognize the *.vrm extension.

It's a glTF with some extra additions. Not sure why they cannot just
keep the file extension and expose their stuff via glTF extensions, but
whatever.

doc/changelog.dox

@@ -967,7 +967,7 @@ See also:
     in @relativeref{Trade,AnyImageConverter}
 -   Recognizing WebP files in @relativeref{Trade,AnyImageConverter}
 -   Recognizing glTF files in @relativeref{Trade,AnySceneConverter}
--   Recognizing 3MF files in @relativeref{Trade,AnySceneImporter}
+-   Recognizing 3MF and VRM files in @relativeref{Trade,AnySceneImporter}
 -   Recognizing OpenVBD files in @relativeref{Trade,AnyImageImporter} and
     @relativeref{Trade,AnyImageConverter}
 -   @ref Audio::AnyImporter "AnyAudioImporter",

src/MagnumPlugins/AnySceneImporter/AnySceneImporter.cpp

@@ -106,7 +106,9 @@ void AnySceneImporter::doOpenFile(const Containers::StringView filename) {
     else if(normalizedExtension == ".fbx"_s)
         plugin = "FbxImporter"_s;
     else if(normalizedExtension == ".gltf"_s ||
-            normalizedExtension == ".glb"_s)
+            normalizedExtension == ".glb"_s ||
+            /* https://github.com/vrm-c/vrm-specification/blob/master/specification/0.0/README.md#file-extension */
+            normalizedExtension == ".vrm"_s)
         plugin = "GltfImporter"_s;
     else if(normalizedExtension == ".ifc"_s)
         plugin = "IfcImporter"_s;

src/MagnumPlugins/AnySceneImporter/AnySceneImporter.h

@@ -71,8 +71,8 @@ tries to open the file with it. Supported formats:
 -   DirectX X (`*.x`), loaded with any plugin that provides `DirectXImporter`
 -   AutoCAD DXF (`*.dxf`), loaded with any plugin that provides `DxfImporter`
 -   Autodesk FBX (`*.fbx`), loaded with any plugin that provides `FbxImporter`
--   glTF (`*.gltf`, `*.glb`), loaded with @ref GltfImporter or any other plugin
-    that provides it
+-   glTF (`*.gltf`, `*.glb`) and [VRM](https://vrm.dev/en/) (`*.vrm`), loaded
+    with @ref GltfImporter or any other plugin that provides it
 -   Industry Foundation Classes (IFC/Step) (`*.ifc`), loaded with any plugin
     that provides `IfcImporter`
 -   Irrlicht Mesh and Scene (`*.irrmesh`, `*.irr`), loaded with any plugin that

src/MagnumPlugins/AnySceneImporter/Test/AnySceneImporterTest.cpp

@@ -128,6 +128,7 @@ constexpr struct {
     {"FBX", "autodesk.fbx", "FbxImporter"},
     {"glTF", "khronos.gltf", "GltfImporter"},
     {"glTF binary", "khronos.glb", "GltfImporter"},
+    {"VRM", "humanoid.vrm", "GltfImporter"},
     {"OpenGEX", "eric.ogex", "OpenGexImporter"},
     {"Stanford PLY", "bunny.ply", "StanfordImporter"},
     {"Stanford PLY uppercase", "ARMADI~1.PLY", "StanfordImporter"},