Code/HumanoidMocap/Core/Formats/Fbx/FbxMeshParts.cs
A static helper that parses an FBX token tree to extract importable mesh instance names. It finds Geometry nodes, follows Connections to Model nodes linked to those geometries, then returns distinct model names after splitting and trimming.
File Access
#nullable enable annotations
using System;
using System.Collections.Generic;
using System.Linq;
namespace HumanoidMocap.Core.Formats.Fbx;
/// <summary>Names of mesh instances that ModelDoc can import independently.</summary>
public static class FbxMeshParts
{
public static IReadOnlyList<string> ReadNames(byte[] data)
{
var root = FbxTokenizer.Parse(data);
var objects = root.Child("Objects");
var connections = root.Child("Connections");
if (objects is null || connections is null)
return Array.Empty<string>();
var geometries = objects.Children
.Where(n => n.Name == "Geometry" && n.Properties.Count > 0
&& n.Properties[0] is long or int)
.Select(n => n.Prop<long>(0)).ToHashSet();
var models = connections.ChildrenNamed("C")
.Where(n => n.Properties.Count >= 3 && n.Properties[0] is "OO"
&& n.Properties[1] is long or int && n.Properties[2] is long or int
&& geometries.Contains(n.Prop<long>(1)))
.Select(n => n.Prop<long>(2)).ToHashSet();
return objects.Children
.Where(n => n.Name == "Model" && n.Properties.Count >= 2
&& n.Properties[0] is long or int && n.Properties[1] is string
&& models.Contains(n.Prop<long>(0)))
.Select(n => FbxNode.SplitName(n.Prop<string>(1)).Name)
.Where(n => !string.IsNullOrWhiteSpace(n))
.Distinct(StringComparer.OrdinalIgnoreCase).ToArray();
}
}