Minor fixes for compatibility issues with QRally:

- Handle null frame names when matching with animation regex
- Default to skin 0 when the provided skin number is out of range
- Convert polygon vertices directly to Unity coordinate positions

Assets/Scripts/Game/Entity.cs

@@ -1,5 +1,4 @@
 using UnityEngine;
-using UnityEngine.Rendering;
 
 public class Entity
 {
@@ -142,9 +141,9 @@ public class Entity
             return;
 
         var skins = aliasModel.Textures.Skins;
-        if (skinNumber >= 0 && skinNumber < skins.Count)
+        if (skins.Count > 0)
         {
-            var skin = skins[skinNumber];
+            var skin = skins[skinNumber >= 0 && skinNumber < skins.Count ? skinNumber : 0];
             if (skin.Frames.Count > 0)
                 visualStyle.SetAliasModelTextures(material, skin.Frames[0].MainTexture, skin.Frames[0].FullBrightTexture);
         }

Assets/Scripts/Support/AliasModel.cs

@@ -105,7 +105,7 @@ public class AliasModel
         for (int frameIdx = 0; frameIdx < header.numFrames; ++frameIdx)
         {
             // Individual sequences are identified by their prefix
-            string frameName = AnimationRegex.Match(header.frames[frameIdx].name).Value;
+            string frameName = AnimationRegex.Match(header.frames[frameIdx].name ?? "").Value;
             if (animName == null)
             {
                 animName = frameName;

Assets/Scripts/Support/BrushModel.cs

@@ -104,7 +104,7 @@ public class BrushModel
             {
                 for (int vertIdx = 0; vertIdx < polyVerts.Length; ++vertIdx)
                 {
-                    tempVertices.Add(polyVerts[vertIdx].position.ToVector3().ToUnity());
+                    tempVertices.Add(polyVerts[vertIdx].position.ToUnityPosition());
                     tempTextureUVs.Add(polyVerts[vertIdx].textureUV.ToVector2());
                     tempLightmapUVs.Add(polyVerts[vertIdx].lightmapUV.ToVector2());
                 }