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docs/api/math/vector3/cross.md

@@ -0,0 +1,23 @@
+# Vector3::Cross
+
+```cpp
+static Vector3 Cross(const Vector3& a, const Vector3& b)
+```
+
+计算两个 3D 向量的叉积。结果向量同时垂直于 a 和 b。
+
+**参数：**
+- `a` - 第一个向量
+- `b` - 第二个向量
+
+**返回：** `Vector3` - 叉积结果，垂直于 a 和 b 的向量
+
+**复杂度：** O(1)
+
+**示例：**
+
+```cpp
+Vector3 right(1.0f, 0.0f, 0.0f);
+Vector3 up(0.0f, 1.0f, 0.0f);
+Vector3 forward = Vector3::Cross(right, up);  // (0, 0, 1)
+```