feat(scripts): PoC 阶段 2 - Layer10_Protocol + Widget 锚定

computeWidgetAlignment(spirit) 简化版 (水平+垂直居中):
  _alignFlags = 16 | 8
  _horizontalCenter = x + w/2 - 640
  _verticalCenter = 360 - (y + h/2)

emitPrefabJson 仅在 Spirit 父节点是 group (非 Layer 根) 时调用;
root / group-X envelope 沿用默认 _alignFlags=45 全屏铺满.

PoC 验证: Layer00010.xml Protol_Layer (group 37, 4 spirits)
生成 Protol_Layer.prefab — 6 Widget 节点 (1 root + 1 group-37 + 4 spirit),
4 spirit widget 全部 _alignFlags=24.

cocoscreator_projects/scripts/legacy-layer-to-cocos-prefab.mjs

@@ -114,6 +114,39 @@ export function computeContentSize(spirit) {
   };
 }
 
+/**
+ * 计算 Spirit 在其所属 group 内的 cc.Widget 锚定参数 (PoC 阶段 2 简化版).
+ *
+ * 数据源权威: 公式仅处理 Spirit.Y < 360 (上) vs > 360 (下) 与水平偏移, 完全基于
+ * 已知字段 (x/y/w/h). SizeCalcMode / CoordRelaX / CoordRelaY 等逆向未出的字段
+ * 暂不支持 — 由 buildSpiritBlock 调用方保证父 group 已经处理 SizeCalcMode ≠ 0.
+ *
+ * 简化规则:
+ *   _alignFlags = 16 | 8   # 16=水平居中, 8=垂直居中
+ *   _horizontalCenter = x + w/2 - 640   # 像素偏移, 1280 坐标系水平中心
+ *   _verticalCenter   = 360 - (y + h/2) # Y-up 翻转 + 720 坐标系垂直中心
+ *
+ * @param {{ x?: string, y?: string, w?: string, h?: string }} spirit
+ * @returns {object} cc.Widget 字段 (除 __type__/node/__prefab/_id 外)
+ */
+export function computeWidgetAlignment(spirit) {
+  const x = parseFloat(spirit.x || '0');
+  const y = parseFloat(spirit.y || '0');
+  const w = parseFloat(spirit.w || '0');
+  const h = parseFloat(spirit.h || '0');
+  return {
+    _alignFlags: 16 | 8,                                   // 水平居中 + 垂直居中
+    _target: null,
+    _left: 0, _right: 0, _top: 0, _bottom: 0,
+    _horizontalCenter: x + w / 2 - 640,                     // 1280 体系半宽
+    _verticalCenter: 360 - (y + h / 2),                    // Y-up + 720 体系半高
+    _isAbsLeft: true, _isAbsRight: true, _isAbsTop: true, _isAbsBottom: true,
+    _isAbsHorizontalCenter: true, _isAbsVerticalCenter: true,
+    _originalWidth: 0, _originalHeight: 0,
+    _alignMode: 2, _lockFlags: 0,
+  };
+}
+
 /**
  * 将 Spirit 记录按 BelongGroupID 归类, 生成 group-X 父节点集合 + Layer 根直挂子节点.
  *
@@ -365,6 +398,25 @@ function makeWidget(nodeId, compPrefabId) {
   };
 }
 
+// Spirit 专用的 Widget 工厂: 调用 computeWidgetAlignment 计算锚定参数.
+// 用法: buildSpiritBlock 在父节点是 group 时调用此工厂, 替代默认 makeWidget.
+// 注意: 此工厂只应在 parent 确实是 group 容器 (而非 Layer 根) 时调用 — 见
+// buildSpiritBlock 的入参语义. Layer 根与 group-X 末尾 envelope 仍用 makeWidget.
+function makeSpiritWidget(nodeId, compPrefabId, spirit) {
+  const align = computeWidgetAlignment(spirit);
+  return {
+    __type__: 'cc.Widget',
+    _name: '',
+    _objFlags: 0,
+    __editorExtras__: {},
+    node: { __id__: nodeId },
+    _enabled: true,
+    __prefab: { __id__: compPrefabId },
+    ...align,                                              // _alignFlags, _horizontal/verticalCenter...
+    _id: '',
+  };
+}
+
 function makeSprite(nodeId, compPrefabId, spriteFrameUuid, type = 0) {
   return {
     __type__: 'cc.Sprite',
@@ -574,7 +626,7 @@ export function emitPrefabJson(layer) {
       if (!spirit) {
         throw new Error(`emitPrefabJson: spirit id ${spiritId} referenced by ${gi.group.name} but not found in layer.spirits`);
       }
-      const info = buildSpiritBlock(spirit, { __id__: gi.nodeId }, out);
+      const info = buildSpiritBlock(spirit, { __id__: gi.nodeId }, out, { parentIsGroup: true });
       spiritInfo.set(spiritId, info);
       gi.node._children.push({ __id__: info.nodeId });
     }
@@ -585,7 +637,7 @@ export function emitPrefabJson(layer) {
     if (!spirit) {
       throw new Error(`emitPrefabJson: root child spirit id ${spiritId} not found in layer.spirits`);
     }
-    const info = buildSpiritBlock(spirit, { __id__: rootId }, out);
+    const info = buildSpiritBlock(spirit, { __id__: rootId }, out, { parentIsGroup: false });
     spiritInfo.set(spiritId, info);
     rootNode._children.push({ __id__: info.nodeId });
   }
@@ -605,8 +657,15 @@ export function emitPrefabJson(layer) {
  * 构造单个 Spirit 的所有对象 (Node + UITransform + CompPrefabInfo + 主组件 +
  * CompPrefabInfo + Widget + CompPrefabInfo + PrefabInfo), 按 schema 顺序 push
  * 到 out 数组, 返回关键 id 供外层 wiring.
+ *
+ * @param {object} spirit - Spirit 字段
+ * @param {{ __id__: number }} parentRef - 父节点引用
+ * @param {Array<object>} out - 输出 JSON 数组
+ * @param {{ parentIsGroup: boolean }} [opts] - parentIsGroup=true 时 Widget
+ *   走 computeWidgetAlignment (锚定 = 水平/垂直居中); false (Layer 根直挂)
+ *   走默认 makeWidget (_alignFlags=45 全屏铺满).
  */
-function buildSpiritBlock(spirit, parentRef, out) {
+function buildSpiritBlock(spirit, parentRef, out, opts = { parentIsGroup: false }) {
   const lpos = computeLpos(spirit);
   const size = computeContentSize(spirit);
   const componentName = mapSpiritTypeToComponent(spirit.type);
@@ -656,7 +715,11 @@ function buildSpiritBlock(spirit, parentRef, out) {
   const widgetCompInfo = makeCompPrefabInfo();
   out.push(widgetCompInfo);
   const widgetCompInfoId = out.length - 1;
-  const widget = makeWidget(nodeId, widgetCompInfoId);
+  // parentIsGroup 时走 computeWidgetAlignment (水平+垂直居中); Layer 根直挂时
+  // 用默认 _alignFlags=45 (全屏铺满占位, 后续 PoC 阶段再细化).
+  const widget = opts.parentIsGroup
+    ? makeSpiritWidget(nodeId, widgetCompInfoId, spirit)
+    : makeWidget(nodeId, widgetCompInfoId);
   out.push(widget);
   const widgetId = out.length - 1;