Нормализация порога у автоматически созданной LODGroup для корректной генерации LOD'ов

Editor/Tools/LightmapTransferTool.cs

@@ -4125,6 +4125,8 @@ void GenerateLods()
 
             var lods = ctx.LodGroup.GetLODs();
             var newLods = new List<LOD>(lods);
+            LodGenerationTool.NormalizeSingleLodTransitionForGeneration(
+                newLods, ctx.SourceLodIndex + 1);
 
             UvProgress.Begin("Generate LODs", cancelable: true);
             try

Editor/Tools/LodGenerationTool.cs

@@ -344,6 +344,11 @@ void ExecGenerateLods(int startLod)
             var lods = ctx.LodGroup.GetLODs();
             var newLods = new List<LOD>(lods);
 
+            // A group created from unlabelled renderers uses a low value so its only
+            // LOD is not culled early. Restore the normal LOD0 transition before
+            // appending generated levels; otherwise they start at 0.005 and below.
+            NormalizeSingleLodTransitionForGeneration(newLods, startLod);
+
             UvProgress.Begin($"Generate LODs ({generateLodCount} levels)", cancelable: true);
             try
             {
@@ -599,6 +604,15 @@ internal static LODGroup CreateLodGroupStatic(List<(GameObject go, int lodIndex)
             return lodGroup;
         }
 
+        internal static void NormalizeSingleLodTransitionForGeneration(List<LOD> lods, int startLod)
+        {
+            if (startLod != 1 || lods.Count != 1 ||
+                !Mathf.Approximately(lods[0].screenRelativeTransitionHeight, 0.01f))
+                return;
+
+            lods[0] = new LOD(0.5f, lods[0].renderers);
+        }
+
         internal static LODGroup CreateLodGroupFromRenderers(GameObject root)
         {
             var renderers = root.GetComponentsInChildren<Renderer>();

Tests/Editor/LodGenerationToolTests.cs

@@ -0,0 +1,39 @@
+using System.Collections.Generic;
+using NUnit.Framework;
+using UnityEngine;
+
+namespace SashaRX.UnityMeshLab.Tests
+{
+    public class LodGenerationToolTests
+    {
+        [Test]
+        public void NormalizeSingleLodTransitionForGeneration_AutoCreatedGroup_RestoresLod0Transition()
+        {
+            var lods = new List<LOD> { new LOD(0.01f, new Renderer[0]) };
+
+            LodGenerationTool.NormalizeSingleLodTransitionForGeneration(lods, 1);
+
+            Assert.AreEqual(0.5f, lods[0].screenRelativeTransitionHeight);
+        }
+
+        [Test]
+        public void NormalizeSingleLodTransitionForGeneration_ExistingTransition_PreservesValue()
+        {
+            var lods = new List<LOD> { new LOD(0.25f, new Renderer[0]) };
+
+            LodGenerationTool.NormalizeSingleLodTransitionForGeneration(lods, 1);
+
+            Assert.AreEqual(0.25f, lods[0].screenRelativeTransitionHeight);
+        }
+
+        [Test]
+        public void NormalizeSingleLodTransitionForGeneration_NotAppendingAfterLod0_PreservesValue()
+        {
+            var lods = new List<LOD> { new LOD(0.01f, new Renderer[0]) };
+
+            LodGenerationTool.NormalizeSingleLodTransitionForGeneration(lods, 2);
+
+            Assert.AreEqual(0.01f, lods[0].screenRelativeTransitionHeight);
+        }
+    }
+}