refactor into projects

MshLib/Msh0x03.cs

@@ -0,0 +1,43 @@
+using System.Buffers.Binary;
+using Common;
+using NResLib;
+
+namespace MshLib;
+
+/// <summary>
+/// MSH-компонент 0x03: позиции вершин
+/// </summary>
+public class Msh0x03
+{
+    public static List<Vector3> ReadComponent(FileStream mshFs, NResArchive mshNres)
+    {
+        var verticesFileEntry = mshNres.Files.FirstOrDefault(x => x.FileType == "03 00 00 00");
+
+        if (verticesFileEntry is null)
+        {
+            throw new Exception("Archive doesn't contain vertices file (03)");
+        }
+
+        if (verticesFileEntry.ElementSize != 12)
+        {
+            throw new Exception("Vertices file (03) element size is not 12");
+        }
+
+        if (verticesFileEntry.FileLength % verticesFileEntry.ElementSize != 0)
+        {
+            throw new Exception("Positions component (0x03) payload size is not divisible by element size");
+        }
+
+        var verticesFile = new byte[verticesFileEntry.FileLength];
+        mshFs.Seek(verticesFileEntry.OffsetInFile, SeekOrigin.Begin);
+        mshFs.ReadExactly(verticesFile, 0, verticesFile.Length);
+
+        var vertices = verticesFile.Chunk(12).Select(x => new Vector3(
+                BinaryPrimitives.ReadSingleLittleEndian(x.AsSpan(0)),
+                BinaryPrimitives.ReadSingleLittleEndian(x.AsSpan(4)),
+                BinaryPrimitives.ReadSingleLittleEndian(x.AsSpan(8))
+            )
+        ).ToList();
+        return vertices;
+    }
+}