shader修改

Assets/Shaders/Editor/UIMaskDrawers.cs

@@ -99,3 +99,105 @@ public class UIMaskChannel : UIMaskEnumDrawer
         // 下拉框的值本身就是要采样的通道号，无需同步到别的属性
     }
 }
+
+// 通用模块：粒子自定义数据通道下拉框（shader 里写 [CustomDataChannel]）
+// 选项 9 项：null / Custom1.xyzw / Custom2.xyzw；值 0=null，1~4=Custom1，5~8=Custom2
+// 右侧会提示该通道是否已被同一材质上的其它参数占用
+//（约定：属性名里含 "CustomChannel" 的都会被统计，以后新增参数只要按这个命名即可自动纳入）
+// shader 侧配套函数：CustomDataChannelValue(custom1, custom2, channel) → 取对应通道的值
+public class CustomDataChannel : MaterialPropertyDrawer
+{
+    private static readonly string[] Items =
+    {
+        "null",
+        "Custom1.x", "Custom1.y", "Custom1.z", "Custom1.w",
+        "Custom2.x", "Custom2.y", "Custom2.z", "Custom2.w"
+    };
+
+    private const float HintWidth = 150f;
+
+    public override float GetPropertyHeight(MaterialProperty prop, string label, MaterialEditor editor)
+    {
+        return EditorGUIUtility.singleLineHeight;
+    }
+
+    public override void OnGUI(Rect position, MaterialProperty prop, string label, MaterialEditor editor)
+    {
+        Rect popupRect = new Rect(position.x, position.y, Mathf.Max(60f, position.width - HintWidth - 4f), position.height);
+        Rect hintRect = new Rect(position.xMax - HintWidth, position.y, HintWidth, position.height);
+
+        int index = Mathf.Clamp(Mathf.RoundToInt(prop.floatValue), 0, Items.Length - 1);
+
+        EditorGUI.BeginChangeCheck();
+        EditorGUI.showMixedValue = prop.hasMixedValue;
+        index = EditorGUI.Popup(popupRect, label, index, Items);
+        EditorGUI.showMixedValue = false;
+        if (EditorGUI.EndChangeCheck())
+        {
+            prop.floatValue = index;
+        }
+
+        bool occupied;
+        string hint = DescribeOccupation(editor, prop, index, out occupied);
+        var hintContent = new GUIContent(hint, "数据来自粒子系统的「自定义数据」模块；"
+            + "还需要在粒子渲染器的「自定义顶点流」里按 UV、Custom1.xyzw、Custom2.xyzw 的顺序勾选对应通道。");
+
+        Color oldColor = GUI.color;
+        if (index == 0)
+        {
+            GUI.color = new Color(0.7f, 0.7f, 0.7f);
+        }
+        else
+        {
+            GUI.color = occupied ? new Color(1f, 0.72f, 0.25f) : new Color(0.55f, 0.85f, 0.55f);
+        }
+        EditorGUI.LabelField(hintRect, hintContent, EditorStyles.miniLabel);
+        GUI.color = oldColor;
+    }
+
+    private static string DescribeOccupation(MaterialEditor editor, MaterialProperty prop, int index, out bool occupied)
+    {
+        occupied = false;
+
+        if (index == 0)
+        {
+            return "未使用";
+        }
+
+        var material = editor.targets.Length > 0 ? editor.targets[0] as Material : null;
+        if (material == null)
+        {
+            return string.Empty;
+        }
+
+        Shader shader = material.shader;
+        int count = ShaderUtil.GetPropertyCount(shader);
+        var owners = new System.Collections.Generic.List<string>();
+
+        for (int i = 0; i < count; i++)
+        {
+            string name = ShaderUtil.GetPropertyName(shader, i);
+            if (name == prop.name || !name.Contains("CustomChannel"))
+            {
+                continue;
+            }
+            if (!material.HasProperty(name) || Mathf.RoundToInt(material.GetFloat(name)) != index)
+            {
+                continue;
+            }
+
+            string description = ShaderUtil.GetPropertyDescription(shader, i);
+            owners.Add(string.IsNullOrEmpty(description) ? name : description);
+        }
+
+        if (owners.Count == 0)
+        {
+            return "未占用";
+        }
+
+        occupied = true;
+        return owners.Count == 1
+            ? "已被 " + owners[0] + " 占用"
+            : "已被 " + owners[0] + " 等 " + owners.Count + " 处占用";
+    }
+}