unreal-modeling

网格建模

建模通过两条路径完成：MeshOperationLibrary（生命周期管理 + 类型桥接）和 GeometryScript 原生库（600+ 函数，通过 UCP 通用 call 直接调用）。

前置条件：UE 编辑器运行中，UCP 插件已启用。传输层规则见 unreal-client-protocol。

MeshOperationLibrary

CDO：/Script/UnrealClientProtocolEditor.Default__MeshOperationLibrary

生命周期

函数	参数	说明
CreateDynamicMesh	—	创建空的临时 DynamicMesh，返回对象路径
ReleaseDynamicMesh	Mesh	标记 mesh 等待 GC 回收
ReleaseAllDynamicMeshes	—	释放所有已跟踪的 mesh
ListDynamicMeshes	—	列出所有已跟踪 mesh 的路径

摘要

函数	参数	说明
GetMeshSummary	TargetMesh	返回 JSON：vertexCount、triangleCount、uvSetCount、bounds、hasNormals、hasVertexColors、hasMaterialIDs、hasPolygroups、isClosed、isDense

资产读写

函数	参数	说明
CopyFromStaticMesh	TargetMesh, SourceStaticMesh	将 StaticMesh 加载到 DynamicMesh（默认选项）
CopyToStaticMesh	SourceMesh, TargetStaticMesh	将 DynamicMesh 写回已有 StaticMesh
CopyToNewStaticMeshAsset	SourceMesh, AssetPath	创建新 StaticMesh 资产，返回资产路径

Selection 桥接

GeometryScript 的 FGeometryScriptMeshSelection 内部使用不可序列化的 TSharedPtr 存储数据，无法通过 JSON 传递。以下函数从可序列化的输入创建 Selection：

函数	参数	说明
SelectAllTriangles	TargetMesh	选择全部三角形
SelectTrianglesByIDs	TargetMesh, TriangleIDs(int 数组)	按 ID 选择三角形
SelectVerticesByIDs	TargetMesh, VertexIDs(int 数组)	按 ID 选择顶点
SelectPolygroupByID	TargetMesh, PolygroupID, GroupLayer	按 Polygroup 选择
SelectMaterialByID	TargetMesh, MaterialID	按材质 ID 选择
GetSelectionIDs	Selection	从 Selection 提取 ID 数组

数据类型桥接

GeometryScript 的列表类型（FGeometryScriptIndexList、FGeometryScriptVectorList 等）将数据存储在不可序列化的 TSharedPtr<TArray<...>> 中。用 Make* 从数组创建，用 Get*Array 提取：

Make 函数	Get 函数	桥接类型
MakeIndexList(Indices, IndexType)	GetIndexListArray	FGeometryScriptIndexList
MakeVectorList(Vectors)	GetVectorListArray	FGeometryScriptVectorList
MakePolyPath(Points, bClosedLoop)	GetPolyPathArray	FGeometryScriptPolyPath
MakeSimplePolygon(Vertices)	GetSimplePolygonArray	FGeometryScriptSimplePolygon
MakeColorList(Colors)	GetColorListArray	FGeometryScriptColorList
MakeUVList(UVs)	GetUVListArray	FGeometryScriptUVList
MakeScalarList(Scalars)	GetScalarListArray	FGeometryScriptScalarList
MakeTriangleList(Triangles)	GetTriangleListArray	FGeometryScriptTriangleList

直接调用 GeometryScript

GeometryScript 函数是标准的 BlueprintCallable 静态函数，通过 UCP 通用 call + CDO 路径调用。

CDO 路径格式

/Script/GeometryScriptingCore.Default__GeometryScriptLibrary_<类名>

示例：/Script/GeometryScriptingCore.Default__GeometryScriptLibrary_MeshRepairFunctions

参数规则

• UDynamicMesh*：传路径字符串，如 "/Engine/Transient.DynamicMesh_0"
• USTRUCT Options：传 JSON 对象，只写需要覆盖的字段，省略的字段使用默认值
• UENUM：传字符串，即枚举值名，如 "Automatic"、"AttributeAware"
• out 参数（如 Outcome、NumFilledHoles）：输入时省略，结果中自动返回
• Debug：省略（默认 nullptr）
• WorldContextObject：UCP 自动注入

返回值

多数 GeometryScript 函数返回 UDynamicMesh*（同一个对象，原地修改）。响应中包含 mesh 路径和所有 out 参数。

标准工作流

示例 1：加载 → 简化 → 写回

// 1. 创建工作 mesh
{"object":"/Script/UnrealClientProtocolEditor.Default__MeshOperationLibrary","function":"CreateDynamicMesh"}

// 2. 从 StaticMesh 加载
{"object":"/Script/UnrealClientProtocolEditor.Default__MeshOperationLibrary","function":"CopyFromStaticMesh","params":{"TargetMesh":"/Engine/Transient.DynamicMesh_0","SourceStaticMesh":"/Game/Meshes/SM_Rock.SM_Rock"}}

// 3. 简化到 5000 三角形
{"object":"/Script/GeometryScriptingCore.Default__GeometryScriptLibrary_MeshSimplifyFunctions","function":"ApplySimplifyToTriangleCount","params":{"TargetMesh":"/Engine/Transient.DynamicMesh_0","TriangleCount":5000,"Options":{"Method":"AttributeAware"}}}

// 4. 写回
{"object":"/Script/UnrealClientProtocolEditor.Default__MeshOperationLibrary","function":"CopyToStaticMesh","params":{"SourceMesh":"/Engine/Transient.DynamicMesh_0","TargetStaticMesh":"/Game/Meshes/SM_Rock.SM_Rock"}}

// 5. 释放
{"object":"/Script/UnrealClientProtocolEditor.Default__MeshOperationLibrary","function":"ReleaseDynamicMesh","params":{"Mesh":"/Engine/Transient.DynamicMesh_0"}}

示例 2：创建图元 → 保存为新资产

// 1. 创建 mesh
{"object":"/Script/UnrealClientProtocolEditor.Default__MeshOperationLibrary","function":"CreateDynamicMesh"}

// 2. 追加 Box 图元
{"object":"/Script/GeometryScriptingCore.Default__GeometryScriptLibrary_MeshPrimitiveFunctions","function":"AppendBox","params":{"TargetMesh":"/Engine/Transient.DynamicMesh_0","PrimitiveOptions":{},"DimensionX":100,"DimensionY":100,"DimensionZ":100}}

// 3. 自动生成 UV
{"object":"/Script/GeometryScriptingCore.Default__GeometryScriptLibrary_MeshUVFunctions","function":"AutoGenerateXAtlasMeshUVs","params":{"TargetMesh":"/Engine/Transient.DynamicMesh_0","UVSetIndex":0,"Options":{}}}

// 4. 保存为新资产
{"object":"/Script/UnrealClientProtocolEditor.Default__MeshOperationLibrary","function":"CopyToNewStaticMeshAsset","params":{"SourceMesh":"/Engine/Transient.DynamicMesh_0","AssetPath":"/Game/Generated/SM_Box"}}

// 5. 释放
{"object":"/Script/UnrealClientProtocolEditor.Default__MeshOperationLibrary","function":"ReleaseDynamicMesh","params":{"Mesh":"/Engine/Transient.DynamicMesh_0"}}

示例 3：布尔合并

// 1-2. 创建两个 mesh 并填充（CreateDynamicMesh + AppendSphere / AppendBox）

// 3. 布尔合并
{"object":"/Script/GeometryScriptingCore.Default__GeometryScriptLibrary_MeshBooleanFunctions","function":"ApplyMeshBoolean","params":{"TargetMesh":"/Engine/Transient.DynamicMesh_0","TargetTransform":{"Rotation":{"X":0,"Y":0,"Z":0,"W":1},"Translation":{"X":0,"Y":0,"Z":0},"Scale3D":{"X":1,"Y":1,"Z":1}},"ToolMesh":"/Engine/Transient.DynamicMesh_1","ToolTransform":{"Rotation":{"X":0,"Y":0,"Z":0,"W":1},"Translation":{"X":50,"Y":0,"Z":0},"Scale3D":{"X":1,"Y":1,"Z":1}},"BooleanOperation":"Union","Options":{}}}

// 4. 释放 mesh B
{"object":"/Script/UnrealClientProtocolEditor.Default__MeshOperationLibrary","function":"ReleaseDynamicMesh","params":{"Mesh":"/Engine/Transient.DynamicMesh_1"}}

GeometryScript 库索引

每个库对应一个域 Skill，包含完整的函数签名、Options 结构体字段、枚举值和 JSON 示例：

域 Skill	覆盖的库
unreal-modeling-primitives	MeshPrimitiveFunctions、MeshModelingFunctions、PolyPathFunctions、SimplePolygonFunctions、PolygonListFunctions
unreal-modeling-meshops	MeshRepairFunctions、MeshSimplifyFunctions、RemeshingFunctions、MeshBooleanFunctions、MeshVoxelFunctions、MeshDecompositionFunctions、MeshBasicEditFunctions、MeshSubdivideFunctions、OpenSubdivFunctions
unreal-modeling-uv	MeshUVFunctions
unreal-modeling-normals	MeshNormalsFunctions
unreal-modeling-deform	MeshDeformFunctions、MeshTransformFunctions
unreal-modeling-query	MeshQueryFunctions、MeshSpatialFunctions、MeshSamplingFunctions、ContainmentFunctions、MeshComparisonFunctions、MeshGeodesicFunctions
unreal-modeling-selection	MeshSelectionFunctions
unreal-modeling-attributes	MeshVertexColorFunctions、MeshPolygroupFunctions、MeshMaterialFunctions
unreal-modeling-asset	StaticMeshFunctions、CreateNewAssetFunctions、CollisionFunctions、EditorDynamicMeshFunctions

关键规则

1. 先创建再操作：调用 GeometryScript 前必须有 DynamicMesh（通过 CreateDynamicMesh 或 CopyFromStaticMesh 获取）
2. 用完即释放：调用 ReleaseDynamicMesh 避免临时对象堆积
3. 原地修改：多数 GeometryScript 函数原地修改 mesh 并返回同一个 UDynamicMesh*
4. Options 可选：USTRUCT Options 参数有合理默认值，只传需要覆盖的字段
5. 不可序列化类型用桥接函数：当 GeometryScript 函数需要 FGeometryScriptMeshSelection、FGeometryScriptIndexList、FGeometryScriptPolyPath 等类型时，用 MeshOperationLibrary 的桥接函数从普通数组创建
6. 用 DescribeObject 探索：对任意 GeometryScript CDO 调用 DescribeObject 可查看完整函数列表和签名