diff --git a/apps/ai-game-creator-shell/src-tauri/src/ui_editor/commands/merge.rs b/apps/ai-game-creator-shell/src-tauri/src/ui_editor/commands/merge.rs
index 85c0801cc..254d43774 100644
--- a/apps/ai-game-creator-shell/src-tauri/src/ui_editor/commands/merge.rs
+++ b/apps/ai-game-creator-shell/src-tauri/src/ui_editor/commands/merge.rs
@@ -3,7 +3,6 @@ use crate::config::load_game_creator_app_config;
 use crate::ui_editor::commands::utils::{
     parse_limited_llm_tool_arguments, request_ui_editor_llm, strict_json_schema,
 };
-use crate::ui_editor::layout::offset::NodeOffset;
 use crate::ui_editor::state::{State, UITree};
 use platform_llm::{LlmFunctionTool, LlmMessage, LlmRunRequest, LlmToolChoice};
 use serde::{Deserialize, Serialize};
diff --git a/apps/ai-game-creator-shell/src/view/ui-editor/useUiEditorPage.ts b/apps/ai-game-creator-shell/src/view/ui-editor/useUiEditorPage.ts
index 2698992f5..98eef005c 100644
--- a/apps/ai-game-creator-shell/src/view/ui-editor/useUiEditorPage.ts
+++ b/apps/ai-game-creator-shell/src/view/ui-editor/useUiEditorPage.ts
@@ -1028,9 +1028,13 @@ export function useUiEditorSession(
           state: snapshot,
         });
         const nextState = applyRecognitionResult(snapshot, result);
-        nextState.ui_trees = nextState.ui_trees.map((tree) =>
-          createTree(nextState, tree.src_ui_design, tree.root),
-        );
+        const recognizedTrees = nextState.ui_trees;
+        nextState.ui_trees = [];
+        for (const tree of recognizedTrees) {
+          nextState.ui_trees.push(
+            createTree(nextState, tree.src_ui_design, tree.root),
+          );
+        }
         editor.replaceState(nextState);
         setHasRecognized(true);
         setSelectedNodeId(null);
@@ -1066,9 +1070,13 @@ export function useUiEditorSession(
       await editor.runWithStateLocked(async (snapshot) => {
         const result = await invoke<MergeDTO>('merge_ui', { state: snapshot });
         const nextState = applyMergeResult(snapshot, result);
-        nextState.ui_trees = nextState.ui_trees.map((tree) =>
-          createTree(nextState, tree.src_ui_design, tree.root),
-        );
+        const mergedTrees = nextState.ui_trees;
+        nextState.ui_trees = [];
+        for (const tree of mergedTrees) {
+          nextState.ui_trees.push(
+            createTree(nextState, tree.src_ui_design, tree.root),
+          );
+        }
         editor.replaceState(nextState);
         setSelectedNodeId(null);
         setMergeStatus('已生成合并后的单棵界面树。');
diff --git a/docs/technical/【前端架构】UI编辑会话模块边界-2026-08-19.md b/docs/technical/【前端架构】UI编辑会话模块边界-2026-08-19.md
index 12460d0e0..120aecb49 100644
--- a/docs/technical/【前端架构】UI编辑会话模块边界-2026-08-19.md
+++ b/docs/technical/【前端架构】UI编辑会话模块边界-2026-08-19.md
@@ -19,6 +19,14 @@
 
 保存与代码生成共享同一份持久化 State/revision。会话层在保存或生成进行期间互斥拦截，且代码生成必须基于已加载的持久化 revision；视图层的保存按钮和“保存并返回”按钮同步遵守该互斥状态。
 
+## 2026-09-14 多树预览与树级偏移
+
+UI 编辑器预览同时渲染 State 中全部 `ui_trees`。每棵树的 `root.offset` 包含 `min` / `max`；当前仅读取 `min` 作为树 wrapper 的左上角，`max` 由 `min + 对应界面图 pixel_size / pixels_per_unit` 派生。所有新树必须经 `createTree` 创建：首棵树位置为 `[0, 0]`，后续树按现有树实际右边界最大值加固定 padding 横向排列，并与现有树最小 top 对齐。删除或排序不重排已有树。
+
+预览中原图与树 root 共享同一空间，root 空白区域可拖动整树，拖动结束一次性写回 root offset 并进入撤销/重做；root 不提供 resize，子节点沿用既有手势。预览选中节点不改变左侧图片面板的 `activeImageId`，Inspector 通过节点所属树反查编辑目标。只有首次进入预览和用户手动点击“适配画布”使用全部树联合边界进行 fit。
+
+原有 render mode 已拆为三个会话级临时开关：`showFrame=true`、`showOriginImage=true`、`showComponent=false`。普通节点框线/名称受 `showFrame` 控制，选中节点强调始终保留；原图和组件显示互不耦合。
+
 `UiDesignStateStore` 的 `generateCode(assetId)` 是必需能力，返回成功结果时不得为 nullable；所有注入的 adapter 与测试替身都必须实现该方法。
 
 资源切换时，会话必须清理上一资源的保存/生成错误和生成中状态；普通保存开始时也清理代码生成错误。生成请求若因加载、锁定或 revision 等前置条件被拦截，必须向视图提供可见错误，而不是静默返回。