-Use 512 size as the minimum limit for AutoTile texture scale

Editor/Tiles/AutoTile/AutoTileTemplateUtility.cs

@@ -51,7 +51,10 @@ public static void ApplyTemplateToAutoTile(this AutoTileTemplate template
             autoTile.m_MaskType = template.maskType;
             if (autoTile.m_TextureList == null)
                 autoTile.m_TextureList = new List<Texture2D>();
+            if (autoTile.m_TextureScaleList == null)
+                autoTile.m_TextureScaleList = new List<float>();
             autoTile.m_TextureList.Add(texture);
+            autoTile.m_TextureScaleList.Add(AutoTile.s_DefaultTextureScale);
             foreach (var sprite in sprites)
             {
                 foreach (var templateSprite in template.sprites)

Editor/Tiles/AutoTile/UI/AutoTileEditorElement.cs

@@ -12,6 +12,8 @@ internal class AutoTileEditorElement : VisualElement
     {
         private static readonly string s_StylesheetPath =
             "Packages/com.unity.2d.tilemap.extras/Editor/Tiles/AutoTile/UI/AutoTileEditor.uss";
+
+        private static readonly float s_MaxSliderScale = 2.5f;
 
         private ListView m_TextureList;
         private ScrollView m_TextureScroller;
@@ -146,20 +148,22 @@ private void TexturePropertyChanged(int index, Texture2D texture2D)
                 return;
 
             m_AutoTile.m_TextureList[index] = texture2D;
+            m_AutoTile.m_TextureScaleList[index] = AutoTile.s_DefaultTextureScale;
             TexturesChanged();
         }
 
         private void PopulateTextureScrollView()
         {
             textureToElementMap.Clear();
-            m_TextureScroller.contentContainer.Clear(); 
+            m_TextureScroller.Clear(); 
 
             if (m_TextureList.itemsSource == null)
                 return;
-
-            foreach (var item in m_TextureList.itemsSource)
+
+            var count = Math.Min(m_AutoTile.m_TextureScaleList.Count, m_TextureList.itemsSource.Count);
+            for (var i = 0; i < count; ++i)
             {
-                var texture2D = item as Texture2D;
+                var texture2D = m_TextureList.itemsSource[i] as Texture2D;
                 if (texture2D == null)
                     continue;
 
@@ -203,15 +207,26 @@ private void PopulateTextureScrollView()
                 saveButton.text = "Save";
                 saveButton.userData = at;
                 he.Add(saveButton);
+
+                var minLength = Math.Max(texture2D.width, texture2D.height);
+                var start = 256.0f / minLength;
 
-                var slider = new Slider("Scale", 0.25f, 2.5f, SliderDirection.Horizontal, 0.1f);
-                slider.style.flexGrow = 0.8f;
-                slider.value = 1.0f;
-                slider.RegisterValueChangedCallback(evt => at.ChangeScale(evt.newValue));
+                var sliderValue = Math.Min(Mathf.Max(start, m_AutoTile.m_TextureScaleList[i]), s_MaxSliderScale);
+
+                var slider = new Slider("Scale", start, s_MaxSliderScale, SliderDirection.Horizontal, 0.1f);
+                slider.style.flexGrow = 0.9f;
+                slider.value = Mathf.Max(start, sliderValue);
+                slider.userData = i;
+                slider.RegisterValueChangedCallback(evt =>
+                {
+                    at.ChangeScale(evt.newValue);
+                    m_AutoTile.m_TextureScaleList[(int) slider.userData] = evt.newValue;
+                    SaveTile();
+                });
                 he.Add(slider);
                 ve.Add(he);
 
-                at.ChangeScale(1.0f);
+                at.ChangeScale(sliderValue);
 
                 ve.Add(at);
 
@@ -265,13 +280,19 @@ private void MaskChanged(Sprite sprite, Texture2D sourceTexture, uint oldMask, u
 
         private void ItemListAdded(IEnumerable<int> insertions)
         {
+            // Note: m_AutoTile.m_TextureList is increased before this method
+            foreach (var i in insertions)
+                m_AutoTile.m_TextureScaleList.Insert(i, AutoTile.s_DefaultTextureScale);
             SaveTile();
             m_TextureList.Rebuild();
             TexturesChanged();
         }
 
         private void ItemListRemoved(IEnumerable<int> removals)
         {
+            // Note: m_AutoTile.m_TextureList is reduced after this method ends
+            foreach (var i in removals)
+                m_AutoTile.m_TextureScaleList.RemoveAt(i);
             SaveTile();
             m_TextureList.Rebuild();
             TexturesChanged();
@@ -301,7 +322,6 @@ private void SaveTile()
             }
 
             EditorUtility.SetDirty(autoTile);
-            //AssetDatabase.SaveAssetIfDirty(autoTile);
             SceneView.RepaintAll();
         }
     }

Editor/Tiles/AutoTile/UI/AutoTileTextureSource.cs

@@ -15,7 +15,7 @@ internal class AutoTileTextureSource : ScrollView
         private Image m_TextureElement;
         private AutoTileSpriteSource.ClickState m_ClickState;
         private Action m_EditStopped;
-        
+
         public AutoTileTextureSource(Texture2D texture2D, AutoTile.AutoTileMaskType maskType, Action<Sprite, Texture2D, uint, uint> maskChanged, Action editStopped) : base(ScrollViewMode.VerticalAndHorizontal)
         {
             m_TextureElement = new Image();

Runtime/Tiles/AutoTile/AutoTile.cs

@@ -10,6 +10,8 @@ namespace UnityEngine.Tilemaps
         "https://docs.unity3d.com/Packages/com.unity.2d.tilemap.extras@latest/index.html?subfolder=/manual/AutoTile.html")]
     public class AutoTile : TileBase
     {
+        internal static readonly float s_DefaultTextureScale = 1f;
+
         [Serializable]
         internal abstract class SerializedDictionary<TKey, TValue> : Dictionary<TKey, TValue>, ISerializationCallbackReceiver
         {
@@ -105,6 +107,13 @@ public enum AutoTileMaskType
         /// </summary>
         [SerializeField]
         public List<Texture2D> m_TextureList = new List<Texture2D>();
+
+        /// <summary>
+        /// List of Texture Scale used by the AutoTile
+        /// </summary>
+        [SerializeField]
+        public List<float> m_TextureScaleList = new List<float>();
+
         #endregion
 
         #region Runtime Data
@@ -246,6 +255,16 @@ public void Validate()
                     }
                 }
             }
+
+            if (m_TextureList.Count != m_TextureScaleList.Count)
+            {
+                if (m_TextureList.Count > m_TextureScaleList.Count)
+                    while (m_TextureList.Count - m_TextureScaleList.Count > 0)
+                        m_TextureScaleList.Add(s_DefaultTextureScale);    
+                else if (m_TextureList.Count < m_TextureScaleList.Count)
+                    while (m_TextureScaleList.Count - m_TextureList.Count > 0)
+                        m_TextureScaleList.RemoveAt(m_TextureScaleList.Count-1);
+            }
         }
 
         private uint Convert2x2Mask(uint mask)