The Geometry Scripting library contains a very broad range of functionality, from lowlevel mesh construction and queries, such as building a mesh trianglebytriangle or counting its vertices, to highlevel operations like mesh booleans and intersection tests.
For more information on using the Geometry Scripting library, see Geometry Script Users Guide.
Most functions are available while working in the editor and at runtime. However, some are only available while working in the editor and have been noted in the tables below.
Asset and Component Read/Write
You can use these functions to read and write Dynamic Mesh instances, such as reading and writing to or from an existing or new Asset or Component.
Node Name 
Description 

Copy Mesh From Static Mesh 
Extracts a Dynamic Mesh from a Static Mesh Asset. 
Copy Mesh To Static Mesh 
Updates a Static Mesh Asset with new geometry converted from a Dynamic Mesh. 
Copy Mesh From Component 
Extracts a Dynamic Mesh Actor from any supported Component type, in World or Local space. 
Create New Volume From Mesh 
Creates a new Volume Actor, such as a Blocking Volume, from a Dynamic Mesh Actor. This node only works in the Editor. 
Create New Static Mesh Asset From Mesh 
Creates a new Static Mesh Asset from a Dynamic Mesh Actor. This node only works in the Editor. 
Set Static Mesh Collision From Mesh 
Generates Simple Collision shapes for a Static Mesh Asset based on the input Mesh. 
Set Dynamic Mesh Collision From Mesh 
Generate Simple Collision shapes for a Dynamic Mesh Component based on the input Mesh. 
Copy Collision Meshes From Object 
Extracts the Collision Geometry from From Object and copies it with meshes stored in To Dynamic Mesh.

Reset Dynamic Mesh Collision 
Clears Simple Collisions from the Dynamic Mesh Component. 
Copy Mesh From Skeletal Mesh 
Copies the Skeletal Mesh into the target Dynamic Mesh. 
Copy Mesh To Skeletal Mesh 
Copies the given Dynamic Mesh to the Skeletal Mesh. 
Create New Skeletal Mesh Asset From Mesh 
Create a new Skeletal Mesh Asset from the Target Mesh. This node only works in the Editor. 
Primitive Generation
You can use these functions to generate and append a primitive mesh to the input Dynamic Mesh.
Node Name 
Description 

Append Box 
Adds a 3D box to a specified Dynamic Mesh. 
Append Sphere Lat Long 
Adds a 3D Sphere triangulated using latitude/longitude topology to a Dynamic Mesh. 
Append Sphere Box 
Adds a 3D sphere triangulated using box topology to a Dynamic Mesh. 
Append Capsule 
Adds a 3D Capsule to a Dynamic Mesh. 
Append Cylinder 
Adds a 3D Cylinder (with optional end caps) to a Dynamic Mesh. 
Append Cone 
Adds a 3D cone to a Dynamic Mesh. 
Append Torus 
Adds a 3D torus (donut) or partial torus to a Dynamic Mesh. 
Append Rectangle XY 
Adds a planar Rectangle to a Dynamic Mesh. 
Append Round Rectangle XY 
Adds a planar Rectangle with Rounded Corners (RoundRect) to a Dynamic Mesh. 
Append Disc 
Adds a planar disc to a Dynamic Mesh. 
Append Triangulated Polygon 
Adds a Delaunay triangulation of a planar 2D polygon to a Dynamic Mesh. 
Append Revolve Polygon 
Adds the surfaceofrevolution of a 2D polygon, full or optionallycapped partial revolution to a Dynamic Mesh. 
Append Spiral Revolve Polygon 
Revolves a 2D polygon on a helical path, like one used to create a vertical spiral. 
Append Revolve Path 
Revolves an open 2D path, with optional top and bottom end caps. 
Append Simple Extrude Polygon 
Extrudes a 2D polygon along a vertical path using a selected Dynamic Mesh. 
Append Simple Swept Polygon 
Sweeps a 2D polygon along an arbitrary 3D path using a selected Dynamic Mesh. 
Append Linear Stairs 
Adds a linear staircase using a selected Dynamic Mesh. 
Append Curved Stairs 
Adds a rising circular staircase using a selected Dynamic Mesh. 
Append Mesh Transformed 
Applies each transform to Append Mesh, then adds its geometry to the Target Mesh. 
Append Sweep Polygon 
Sweeps and rotates a 2D polygon along the Sweep Path to create a 3D mesh that appends to the provided mesh. 
Append Voronoi Diagram 2D 
Generates triangulated Voronoi Cells from the provided Voronoi Sites, identifying each with PolyGroups, and appends to the provided mesh. 
Append Sweep Polyline 
Sweep the given 2D Polyline Vertices along the Sweep Path specified as a set of FTransforms. If the 2D vertices are (U,V), then in the coordinate space of the FTransform, X points "along" the path, Y points "right" (U), and Z points "up" (V). 
Append Bounding Box 
Adds a 3D box to the Target Mesh with dimensions and origin taken from the input Box. 
Append Delaunay Triangulation 2D 
Generates a Delaunay Triangulation of the provided vertices, and appends it to the Target Mesh. 
Append Polygon List Triangulation 
Generates a Delaunay Triangulation of the provided Polygon List, and appends it to the Target Mesh. 
Transform and Deformation
You can use these functions to manipulate the vertex positions of a Dynamic Mesh. These manipulations do not change the mesh topology or connectivity.
Node Name 
Description 

Translate Mesh 
Applies a translation to the vertices of a Mesh. 
Scale Mesh 
Applies a scale transformation to the vertices of a Mesh. 
Transform Mesh 
Applies an arbitrary FTransform to the vertices of a Mesh. 
Apply Bend Warp To Mesh 
Applies a bend warp around an axis defined by a Transform. 
Apply Twist Warp To Mesh 
Applies a twist warp around an axis defined by a Transform. 
Apply Flare Warp To Mesh 
Applies a Flare or Bulge warp. 
Apply Math Warp To Mesh 
Applies various simple mathfunctionbased warps, currently a 1D or 2D sinewave with arbitrary orientation. 
Apply Perlin Noise To Mesh 
Applies a 3D Perlin noise displacement to the entire mesh or regions of the mesh defined by optional Selection. 
Apply Iterative Smoothing To Mesh 
Applies several mesh smoothing iterations to the entire mesh or a subset defined by the optional Selection 
Apply Displace From Texture Map 
Applies a displacement to a Dynamic Mesh based on a Texture2D and a UV channel. 
Rotate Mesh 
Rotates the mesh relative to the specified origin. 
Translate Pivot To Location 
Set the Pivot Location for the Mesh. Since the Pivot of a Mesh object is always the point at (0,0,0), this function simply translates the mesh by PivotLocation. 
Make Transform From Z Axis 
Create a transform at the given location, with the ZAxis vector as the Zaxsis of the transform, and the X or Y axis oriented to the tangent vector, based on the 
Make Transform From Axes 
Create a transform at the given location, with the ZAxis vector as the Zaxsis of the transform, and the X or Y axis oriented to the Tangent vector, based on the 
Get Transform Axis Vector 
Get the vector for the direction of the X, Y, and Z axis of the transform. 
Get Transform Axis Ray 
Get the ray at the transform location aligned with the direction of the X,Y, and Zaxis of the transform. 
Get Transform Axis Plane 
Get the plane at the transform location with the plane normal aligned with the direction of the X,Y, and Zaxis of the transform. 
Composition and Decomposition
You can use these functions to combine meshes together, or split them apart.
Node Name 
Description 

Copy Mesh To Mesh 
Copies the mesh from one Dynamic Mesh into another. 
Get Sub Mesh From Mesh 
Copies a list of triangles from one Dynamic Mesh to another. 
Split Mesh By Components 
Separates a mesh into parts, one for each connected component, drawn from a Dynamic MeshPool. 
Split Mesh By Material IDs 
Separates a mesh into parts, one for each Material ID, drawn from a Dynamic MeshPool. 
Append Mesh 
Adds the geometry from one mesh to another, with optional Transform. 
Append Mesh Repeated 
Adds the geometry from one mesh to another based on the number of times it should repeat, accumulating a transform each time. This operation is useful for making patterns. 
Mesh Modeling
These functions provide standard highlevel modeling operations, but are generally calling the lowlevel mesh processing code that the similarlynamed Tool in Modeling Mode would call.
Node Name 
Description 

Apply Mesh Boolean 
Applies a Boolean operation (such as, Union, Intersect, and Subtract) to a Dynamic Mesh based on a second mesh. 
Apply Mesh Plane Cut 
Applies a plane cut to a mesh, optionally filling any holes created. 
Apply Mesh Plane Slice 
Slices a mesh into two halves, with optional hole filling. 
Apply Mesh Mirror 
Mirrors a mesh across a plane, with optional cutting and welding of triangles. 
Apply Mesh Offset 
Moves the vertices of a mesh to an offset surface. 
Apply Mesh Shell 
Moves a copy of the mesh's triangles to an offset surface, and stitches them to the original triangles. For example, to create a thickened shell. 
Apply Mesh Extrude 
Extrudes the triangles of a mesh along a constant direction. For example, it creates a solid from an open triangulated polygon. 
Apply Mesh Solidify 
Replaces the mesh with a voxelizedandmeshed approximation (VoxWrap operation). 
Apply Mesh Morphology 
Replaces the mesh with an SDFbased offset mesh approximation. 
Apply Mesh Self Union 
An object performs a Boolean Union operation with itself, computing actions such as repairing selfintersections and removing floating geometry. 
Apply Mesh PolyGroup Bevel 
Applies Mesh Bevel operation to all PolyGroup Edges. 
Mesh Selections
These functions identify regions of a mesh to different tools so they can operate locally. Several functions can work on the entire mesh or a subset defined by a Selection. Selection Types include: Triangle, Vertices, and PolyGroups.
Node Name 
Description 

Invert Mesh Selection 
Invert the selection on the Target Mesh. 
Create Select All Mesh Selection 
Creates a selection of the given selection type containing all the elements of the Target Mesh 
Convert Mesh Selection 
Converts a mesh selection to a different type. By default, vertices map to triangles within a onering neighborhood, and triangles to all contained vertices. 
Combine Mesh Selections 
Combines two mesh selections into a new mesh selection. The two inputs, Selection A and Selection B must have the same type. 
Convert Index Array To Mesh Selection 
Creates a mesh selection from the Index Array. 
Convert Index Set To Mesh Selection 
Creates a mesh selection from the Index Set. 
Convert Mesh Selection To Index Array 
Converts a mesh selection to an Index Array. 
Convert Index List To Mesh Selection 
Creates a mesh selection from the Index List. For cases where the Index List Type does not match the Selection Type, Convert mesh selection with 
Convert Mesh Selection To Index List 
Converts a mesh selection to an Index List. 
Select Mesh Elements In Box 
Creates a new mesh selection of the Selection Type for the Target Mesh by finding all elements contained in the Box. 
Select Mesh Elements In Box With BVH 
Create a new Mesh Selection of the Selection Type for the Target Mesh by finding all elements contained in the Box. Similar to Select Mesh Elements In Box but takes a BVH to make it work faster. 
Select Mesh Elements In Sphere 
Creates a new mesh selection of the Selection Type for the Target Mesh by finding all elements contained in the Sphere. 
Select Mesh Elements With Plane 
Creates a new mesh selection of the Selection Type for the Target Mesh by finding all elements on one side of the plane, particularly the side that the surface normal of a Plane points towards. 
Select Mesh Elements By Normal Angle 
Creates a new mesh selection of the Selection Type for the Target Mesh by finding all elements that have a normal vector that is within an angular deviation threshold from the given Normal. For Triangle and PolyGroup selections the triangle facet normal is used, for Vertex selections the pervertex averaged normal is used. 
Select Mesh Elements Inside Mesh 
Creates a new mesh selection of the Selection Type for the Target Mesh by finding all elements inside a second Selection Mesh. 
Expand Mesh Selection To Connected 
Expands the Selection on the Target Mesh to connected regions and returns the New Selection. 
Get Mesh Selection Bounding Box 
Gets the 3D Bounding Box of a mesh selection. 
Get Mesh Selection Boundary Loops 
Computes the set of Vertex Loops bordering a mesh selection. Both the 3D polylines and lists of vertex indices are returned for each Loop. For a Vertex selection, this function returns the border loops around the onering neighborhood of the vertex selection. For a Vertex selection, this function returns the border loops around the onering neighborhood of the vertex selection. 
Get Mesh Selection Info 
Queries information about a mesh selection. 
Debug Print Mesh Selection 
Prints information about the mesh selection to the Output Log. 
Expand Contract Mesh Selection 
Grow or shrink the Selection on the Target Mesh to connected neighbors.

Modify Mesh by Selection
Functions for editing geometry from a given selection.
Transform Mesh
Node Name 
Description 

Transform Mesh Selection 
Applies the given transform to the selected part of the mesh. 
Translate Mesh Selection 
Applies the given translation to the selected part of the mesh. 
Rotate Mesh Selection 
Rotates the selected part of the mesh relative to the specified origin. 
Scale Mesh Selection 
Applies the given scale to the selected part of the mesh. 
Materials and PolyGroups
Node Name 
Description 

Set Material ID For Mesh Selection 
Sets a new Material ID on all the triangles of the given Selection. 
Set PolyGroup For Mesh Selection 
Sets a new PolyGroup on all the triangles of the given Selection, for the given Group Layer. 
Mesh Modeling
Node Name 
Description 

Apply Mesh Disconnect Faces 
Disconnects the triangles of the Target Mesh identified by the Selection. 
Apply Mesh Duplicate Faces 
Duplicates the triangles of the Target Mesh identified by the Selection input. 
Apply Mesh Linear Extrude Faces 
Applies Linear Extrusion to the triangles of Target Mesh identified by the Selection. 
Apply Mesh Offset Faces 
Applies an Offset to the faces of the Target Mesh identified by the Selection, or all faces if Selection is empty. 
Apply Mesh Inset Outset Faces 
Applies an Inset or Outset to the faces of Target Mesh identified by the Selection, or all faces if the Selection is empty. 
Apply Mesh Bevel Selection 
Applies a Mesh Bevel operation to parts of Target Mesh using the Bevel Options settings. 
Subdivision
These functions apply various mesh subdivision strategies to a Dynamic Mesh.
Node Name 
Description 

Apply PolyGroup Catmull Clark SubD 
Apply Catmull Clark Subdivision to the PolyGroup Topology of the mesh (discards input triangulation). This node only works in the Editor. 
Apply Triangle Loop SubD 
Apply Loop Subdivision to the input mesh. This node only works in the Editor. 
Apply Selective Tessellation 
Tessellate the specified mesh selection using the indicated Pattern Type. 
Apply PN Tessellation 
Apply pointnormal tessellation to the input mesh. 
Apply Uniform Tessellation 
Apply a uniform tessellation to the input mesh. 
Simplification
These functions simplify a mesh using various strategies.
Node Name 
Description 

Apply Simplify To Triangle Count 
Simplifies the mesh until a target triangle count is reached. 
Apply Simplify To Vertex Count 
Simplifies the mesh until a target vertex count is reached. 
Apply Simplify To Tolerance 
Simplifies the mesh to a target geometric tolerance. For example, any further simplification would result in a deviation from the input mesh larger than the tolerance. 
Apply Simplify To Planar 
Simplifies planar areas of the mesh that have more triangles than necessary. This does not change the 3D shape of the mesh. 
Apply Simplify To PolyGroup Topology 
Simplifies the mesh down to the PolyGroup Topology. For example, the highlevel faces of the mesh PolyGroups. Another example would be on a default BoxSphere where simplifying to PolyGroup topology produces a box. 
Box
Utility functions for computing basic math functions for box objects.
Node 
Description 

Make Box From Center Size 
Create a box from a center point, and X, Y, and Z dimensions. 
Make Box From Center Extents 
Create a box from a center point and X, Y, and Z extents. Extents are halfdimensions. 
Get Box Center Size 
Get the center point, and X, Y, and Z dimensions of a box. 
Get Box Corner 
Get the position of a corner of the box. Corners are indexed from 0 to 7, using an ordering where:

Get Box Face Center 
Get the position of the center of a face of a box. Faces are indexed from 0 to 5, using an ordering where:

Get Box Volume Area 
Get the volume and surface area of a box. 
Get Expanded Box 
Get the input box expanded by adding the Expand By parameter to both the Min and Max. Dimensions will be clamped to the center point if any of the Expand By parameters are larger than half the box size. 
Get Transformed Box 
Apply the input transform to the corners of the input box, and return the new box containing those points. 
Test Box Box Intersection 
Test if box 1 and box 2 intersect. 
Find Box Box Intersection 
Find the box formed by the intersection of box 1 and box 2. 
Get Box Box Distance 
Calculate the minimum distance between box 1 and box 2. 
Test Point Inside Box 
Test if a point is inside the box; returning true if so, otherwise false. 
Find Closest Point On Box 
Find the point on the faces of the box that is closest to the input point. If the point is inside the Box, it is returned. 
Get Box Point Distance 
Calculate the minimum distance between the box and the point. 
Test Box Sphere Intersection 
Check if the box intersects a sphere defined by the Sphere Center and Sphere Radius. 
Normals
These functions recompute the normals of a mesh.
Node Name 
Description 

Flip Normals 
Flips the mesh normals by reversing the orientation of each face. 
Set Per Vertex Normals 
Sets the mesh normals to pervertex normals. For example, no split normals at any vertex. 
Set Mesh To Facet Normals 
Sets the mesh normals to perface/triangle normals. For example, split normals along every edge of the mesh. 
Compute Split Normals 
Computes splitnormals for the mesh based on an angle tolerance and/or other factors such as PolyGroup topology. 
Recompute Normals 
Recomputes the existing mesh normals. Preserves existing split normals. For use after mesh deformations, for example. 
Compute Tangents 
Recomputes tangents for the mesh (various methods). 
Set Mesh Per Vertex Normals 
Set all normals in the Target Mesh Normals Overlay to the specified pervertex normals. 
Get Mesh Has Tangents 
Check if the target mesh has a Tangents Attribute Layer enabled. 
Discard Tangents 
Remove any existing Tangents Attribute Layer from the Target Mesh. 
Compute Tangents 
Recompute tangents for the Target Mesh, using the method specified by 
Set Mesh Per Vertex Tangents 
Set all tangents in the Target Mesh Tangents Overlays to the specified pervertex tangents. 
Get Mesh Per Vertex Tangents 
Compute the interpolated Position, 
Update Vertex Normal 
Update the Normals and Tangents at VertexD of the Target Mesh. 
Recompute Normals For Mesh Selection 
Recompute the normals of Target Mesh on all the triangles/vertices of the given Selection using the given Calculate Options. This method will preserve any existing hard edges, that is each shared trianglevertex normal is recomputed by averaging the face normals of triangles that reference that shared trianglevertex normal. 
Cleanup and Repair
You can use these functions to fix issues in a mesh, or to apply other standard repairs.
Node Name 
Description 

Compact Mesh 
Compacts the mesh's vertices and triangles to remove any "holes" in the Vertex ID or Triangle ID lists (see discussion in LowLevel Mesh Queries section). 
Discard Mesh Attributes 
Removes the Attribute Set from a Dynamic Mesh, such as all UVs, Normals, Material IDs, Vertex Colors, and extended PolyGroup Layers. Note that this may prevent many functions from working. 
Auto Repair Normals 
This function tries to automatically reorient the Normals of a mesh so that they are consistent, such as fixing flipped normals. 
Weld Mesh Edges 
Welds any open boundary edges of the mesh together if possible in order to remove "cracks." 
Fill All Mesh Holes 
Tries to fill all open boundary loops (such as holes in the geometry surface) of a mesh. 
Remove Small Components 
Removes connected components of the mesh that have a volume, area, or triangle count below a threshold. 
Remove Hidden Triangles 
Removes any triangles in the mesh that are not visible from the exterior view, under various definitions of "visible" and "outside." 
Resolve Mesh TJunctions 
Attempts to resolve tjunction in the Target Mesh. 
Split Mesh Bowties 
Splits vertices in the Target Mesh that otherwise produce a bowtie where only a single vertex connects regions of the mesh. 
Repair Mesh Degenerate Geometry 
Modifies the Target Mesh by deleting small triangles or merging triangles until all edges are greater than a specified minimum length. 
LowLevel Mesh Queries
These functions provide lowlevel information about the elements of a mesh. In this context, VertexID and TriangleID are integers.
In a Dynamic Mesh, there may be gaps in VertexID or TriangleID range — after vertices/triangles are deleted — and some operations (like Simplification) may return a mesh with gaps present. Gaps in the ID ranges are cleaned up using the Compact Mesh function.
Node Name 
Description 

Get Vertex Count 
Gets the number of vertices in the mesh. 
Get Num Vertex IDs 
Gets the number of Vertex IDs in the mesh, which may be larger than the Vertex Count, if the mesh is not dense. For example, after deleting vertices. 
Is Valid Vertex ID 
Returns true if a Vertex ID refers to a valid vertex. 
Get All Vertex IDs 
Returns an IndexList of all Vertex IDs in mesh. 
Get Vertex Position 
Gets the 3D position of a mesh vertex, by Vertex ID. 
Get All Vertex Positions 
Returns a Vector List of all the mesh vertex positions. This list may be extensive. 
Get Triangle Count 
Returns the number of triangles in the mesh. Note that this is a function on the Dynamic Mesh directly. 
Get Num Triangle IDs 
Gets the number of Triangle IDs in the mesh. The number may be larger than the Triangle Count if the mesh is not dense, even after deleting triangles. 
Is Valid Triangle ID 
Returns true if a TriangleID refers to a valid Triangle. 
Get All Triangle IDs 
Returns an Index List of all Triangle IDs in a mesh. 
Get Triangle Indices 
Returns the vertex indices triplet for a Triangle. 
Get All Triangle Indices 
Returns a TriangleList of all Triangle indices triplets in a mesh. 
Get Triangle Positions 
Returns the three corner positions for a Triangle. 
Get Triangle Face Normal 
Returns the face/facet normal of a Triangle. 
Get Triangle UVs 
Returns the three corner UVs for a Triangle. 
Get Triangle Material ID 
Returns the current Material ID for a Triangle. 
Get All Triangle Material IDs 
Returns an Index List of all triangle Material IDs. 
Get Triangle PolyGroup ID 
Returns the current PolyGroup ID for a Triangle, in a given PolyGroup layer. 
Get Has Vertex ID Gaps 
Returns true if there are gaps in the Vertex ID list. For example, Get Number of Vertex IDs is greater than Get Vertex Count. 
Get Has Triangle ID Gaps 
Returns true if there are gaps in the Triangle ID list, such that Get Num Triangle IDs is greater than Get Triangle Count. 
Get Is Dense Mesh 
Returns true if the mesh is dense. For example, no gaps in Vertex IDs or Triangle IDs. 
Get Mesh Has Attribute Set 
Returns true if the mesh has an Attribute Set enabled to store UVs, Normals, Material IDs, and Vertex Colors. This is generally enabled by default. 
Get Interpolated Triangle Position 
Compute the interpolated Position, 
Compute Triangle Barycentric Coords 
Compute the barycentric coordinates (A,B,C) of the Points relative to the specified TriangleID of the Target Mesh. 
Get Interpolated Triangle UV 
Compute the interpolated UV, 
Get Triangle Normals 
For the specified TriangleID of the Target Mesh, get the Normal and Tangent vectors at each vertex of the Triangle. These Normals and Tangents will be taken from the Normal and Tangents Overlays. 
Get Interpolated Triangle Normal 
Compute the interpolated Normal, 
Get Triangle Normal Tangents 
For the specified TriangleID of the Target Mesh, get the Normal and Tangent vectors at each vertex of the Triangle. These Normals and Tangents will be taken from the Normal and Tangents Overlays. 
Get Interpolated Triangle Normal Tangents 
Compute the interpolated Normal and Tangents for the specified TriangleID in the Normal and Tangent attributes of the Target Mesh. 
Get Has Vertex Colors 
Return true if the Target Mesh has the Vertex Colors attribute enabled. 
Get Triangle Vertex Colors 
For the specified TriangleID of the Target Mesh, get the Vertex Colors at each vertex of the Triangle. These Colors will be taken from the Vertex Color Attribute. 
Get Interpolated Triangle Vertex Color 
Compute the interpolated Vertex Color, 
LowLevel Mesh Building
These functions construct a mesh trianglebytriangle and perform other lowlevel mesh editing operations.
Using these functions in situations that involve looping over the elements of meshes with many thousands of triangles can be quite slow in Blueprint or Python scripting.
Node Name 
Description 

Set Vertex Position 
Sets the 3D position of a mesh vertex. 
Add Vertex To Mesh 
Adds a new vertex to the mesh and returns a new Vertex ID. 
Add Vertices To Mesh 
Adds a list of vertices to the mesh. 
Delete Vertex From Mesh 
Removes a vertex from the mesh. 
Delete Vertices From Mesh 
Removes a list of vertices from the mesh. 
Add Triangle To Mesh 
Adds a triangle (3element Vertex ID tuple) to the mesh. 
Add Triangles To Mesh 
Adds a list of triangles to the mesh. 
Delete Triangle From Mesh 
Removes a triangle from the mesh. 
Delete Triangles From Mesh 
Removes a list of triangles from the mesh. 
Delete Triangles In PolyGroup 
Deletes all triangles from the mesh that have a particular PolyGroup, in a specific PolyGroup layer. 
Append Buffers To Mesh 
Adds a set of vertices/triangles to the mesh, with attributes such as Normals and UVs. Similar to Create Mesh Section in Proc Mesh Component. 
Set Mesh Triangle Normals 
Sets the Normals of a mesh triangle. 
Set Mesh Triangle UVs 
Sets the UVs of a mesh triangle. 
Set Triangle Material ID 
Sets the Material ID of a mesh triangle. 
Set All Mesh Vertex Positions 
Set all vertex positions in the Target Mesh to the specified positions. 
LowLevel List Management
These functions cover list management for: Index List, Scalar List, Vector List, UV List, and Color List.
Node Name 
Description 

Get Index List Length 
Returns the number of items in the Index List. 
Get Index List Last Index 
Returns the index of the last item in the Index List. 
Get Index List Item 
Returns the item stored in the Index List at the specified location. 
Set Index List Item 
Updates the value of the item stored in the Index List at the specified location. 
Convert Index List To Array 
Converts an Index List to an array of integers. 
Convert Array To Index List 
Converts an array of integers to an Index List. 
Duplicate Index List 
Duplicates the contents Index List into Duplicate List. 
Clear Index List 
Resets all the items in the Index List to the Clear Value. 
Get Scalar List Length 
Returns the number of items in the Scalar List. 
Get Scalar List Last Index 
Returns the index of the last item in the Scalar List. 
Get Scalar List Item 
Returns the Scalar (double) stored in the Scalar List at the specified location. 
Set Scalar List Item 
Updates the value of the Scalar stored in the Scalar List at the specified location. 
Convert Scalar List To Array 
Converts a Scalar List to an array of doubles. 
Convert Array To Scalar List 
Converts an array of doubles to a Scalar List. 
Duplicate Scalar List 
Copies the contents of Scalar List into Duplicate List. 
Clear Scalar List 
Reset all the items in the Scalar List to the Clear Value. 
Get Vector List Length 
Returns the number of items in the Vector List. 
Get Vector List Last Index 
Return the index of the last item in the Vector List. 
Get Vector List Item 
Return the FVector stored in the VectorList at the specified location. 
Set Vector List Item 
Updates the value of the FVector stored in the Vector List at the specified location. 
Convert Vector List To Array 
Converts a Vector List to an array of FVectors. 
Convert Array To Vector List 
Converts an Array of FVectors to a Vector List. 
Duplicate Vector List 
Copies the contents of Vector List into Duplicate Vector List. 
Clear Vector List 
Resets all the items in the Vector List to the Clear Value. 
Get UV List Length 
Returns the number of items in the UV List. 
Get UV List Last Index 
Returns the index of the last item in the UV List. 
Get UV List Item 
Returns the FVector2D stored in the UV List at the specified location. 
Set UV List Item 
Updates the value of the FVector2D stored in the UV List at the specified location. 
Convert UV List To Array 
Converts a UV List to an array of FVector2Ds. 
Convert Array To UV List 
Converts an array of FVector2D to UVList. 
Duplicate UV List 
Duplicates the contents of UV List into Duplicate List. 
Get Color List Length 
Returns the number of items in the Color List. 
Get Color List Last Index 
Returns the index of the last item in the Color List. 
Get Color List Item 
Returns the FLinearColor stored in the Color List at the specified location. 
Set Color List Item 
Updates the value of the FLinearColor stored in the Color List at the specified location. 
Convert Color List To Array 
Converts the Color List to an array of FLinearColor. 
Convert Array To Color List 
Converts an array of FLinearColor to a Color List. 
Extract Color List Channel 
Creates a Scalar List that corresponds to the 0,1, or 2 channel of a Color List. 
Extract Color List Channels 
Creates a Vector List from a Color List. The channels in the Color List are mapped to vector components by means of X Channel Index, Y Channel Index, and Z Channel Index. 
LowLevel Math
Functions that operate on the Vector Lists and Scalar Lists in a component wise fashion. The functions that take multiple lists, such as Vector Dot, require the lists to have the same number of elements.
Node Name 
Description 

Vector Length 
Computes the length of each vector in Vector List A and returns the value in the Scalar List. 
Vector Dot 
Computes the dotproduct between each pair of vectors in Vector List A and Vector List B, and returns the value in the new Scalar List. 
Vector Cross 
Computes the crossproduct between each pair of vectors in Vector List A and Vector List B and returns the value in the new Vector List. 
Vector Normalize In Place 
Normalizes each vector in Vector List, and stores the value in a Vector List. If a vector is degenerate, set the normal to the Set On Failure vector. 
Vector Blend 
Computes By default this (constants = 1) adds the two vectors. Set You can also use the function to Linear Interpolate, by setting 
Vector Blend In Place 
Computes By default this (constants = 1) adds the two vectors. Set You can also use the function to Linear Interpolate, by setting 
Scalar Vector Multiply 
Computes 
Scalar Vector Multiply In Place 
Computes 
Constant Vector Multiply 
Computes 
Constant Vector Multiply In Place 
Computes 
Vector To Scalar 
Converts each Vector in Vector List to a Scalar by computing You can use it to extract the X, Y, and Z values from a Vector, or other componentwise math. 
Scalar Invert 
Computes If Abs(Scalar) < Epsilon, set to Set On Failure value. 
Scalar Invert In Place 
Computes If Abs(Scalar) < Epsilon, set to Set On Failure value. 
Scalar Blend 
Computes By default this (constants = 1) just adds the two values. Set The function can also be used to Linear Interpolate, by setting 
Scalar Blend In Place 
Computes By default this (constants = 1) just adds the two values. Set Can also be used to Linear Interpolate, by setting 
Scalar Multiply 
Computes 
Scalar Multiply In Place 
Computes 
Constant Scalar Multiply 
Computes 
Constant Scalar Multiply In Place 
Computes 
Mesh Sampling
These functions calculate and place points along the surface of a mesh.
Node 
Description 

Compute Point Sampling 
Compute a set of sample points lying on the surface of Target Mesh based on the provided sampling Options. Samples are approximately uniformly distributed, and nonoverlapping relative to the provided Options. 
Compute NonUniform Point Sampling 
Compute a set of sample points lying on the surface of Target Mesh based on the provided sampling Options and NonUniform Options. 
Compute Vertex Weighted Point Sampling 
Compute a set of sample points lying on the surface of TargetMesh based on the provided sampling Options and NonUniform Options. 
Ray
Utility functions for creating and querying rays. A ray is a line which can be used to determine intersections of objects. These are particularly useful for building interactive user interfaces in Blueprints.
Node 
Description 

Make Ray From Points 
Create a ray from two points, placing the origin at A and the direction as Normalize (BA). 
Make Ray From Point Direction 
Create a ray from an origin and direction, with optionally nonnormalized direction. 
Get Transformed Ray 
Apply the given transform to the given ray, or optionally the Transform Inverse, and return the new transformed ray. 
Get Ray Point 
Get a point at the given distance along the Ray, 
Get Ray Start End 
Get two points along the ray. 
Get Ray Parameter 
Project the given point onto the closest point along the ray, and return the ray parameter and distance at that point. 
Get Ray Point Distance 
Get the distance from the given point to the closest point on the ray. 
Get Ray Closest Point 
Get the closest point on the Ray to the given point. 
Get Ray Sphere Intersection 
Check if the ray intersects a sphere defined by the Sphere Center and Sphere Radius. This function returns two intersection distances (ray parameters). If the ray grazes the sphere, both distances will be the same. If it misses, they will be MAX_FLOAT. Use the function Get Ray Point to convert the distances to points on the ray and sphere. 
Get Ray Box Intersection 
Check if the ray intersects a sphere defined by the Sphere Center and Sphere Radius. 
Get Ray Plane Intersection 
Find the intersection of a ray and a plane. 
Get Ray Line Closest Point 
Compute the pair of closest points on a 3D ray and line. The line is defined by an origin and direction, but extends infinitely in both directions. 
Get Ray Segment Closest Point 
Compute the pair of closest points on a 3D ray and line segment. The line segment is defined by its two endpoints. 
Material ID
Functions for manipulating Material IDs of a mesh. A Material ID is a pertriangle integer and is not directly connected to any specific Material. Each Material ID is associated with a Mesh Section when converting to or from a Static Mesh.
Node Name 
Description 

Get Has Material IDs 
Returns true if the mesh has Material IDs available/enabled. 
Enable Material IDs 
Enables Material IDs on a mesh, initialize to 0. 
Clear Material IDs 
Resets all Material IDs on a mesh to 0. 
Get Max Material ID 
Returns the maximum Material ID currently set on a mesh. 
Remap Material IDs 
For all triangles with a Material ID matching a given value, and sets the Material ID to a new value. 
Set All Triangle Material IDs 
Sets the Material ID of all triangles in a mesh to the values in an input Index List. 
Set PolyGroup Material ID 
Sets the Material ID of all triangles in a mesh that have a specified PolyGroup ID (in a given PolyGroup layer) to the specified Material ID. 
Vertex Values
You use these functions to get and manipulate mesh values stored at vertices, including Vertex Colors
Multiple values, such as Normals, can be stored at a given vertex but these methods will only return one.
Node Name 
Description 

Set Mesh Constant Vertex Color 
Sets all vertex colors to a specific color. 
Set Mesh Per Vertex Colors 
Sets the color for every vertex using a Color List. 
Get Mesh Per Vertex Colors 
Gets a list of single vertex colors for each mesh vertex in the Target Mesh, derived from the Vertex Color Overlay. 
Set Mesh Selection Vertex Color 
Sets the colors in the Target Mesh's Vertex Color Overlay, identified by the Selection, to a constant value.

Convert Mesh Vertex Colors SRGB To Linear 
Apply an SRGB to Linear color transformation on all vertex colors. 
Convert Mesh Vertex Colors Linear To SRGB 
Apply a Linear to SRGB color transformation on all vertex colors. 
Get Mesh Per Vertex Normals 
Get a list of single normal vectors for each mesh vertex in the Target Mesh, derived from the Normals Overlay. 
Get Mesh Per Vertex UVs 
Get a list of single vertex UVs for each mesh vertex in the Target Mesh, derived from the specified UV Overlay. 
Blur Mesh Vertex Colors 
Blur the color attribute of the mesh. If the mesh has no color attribute, the function returns the mesh unchanged. 
Texture Sampling and Creation
Functions for reading and creating texture data.
Node Name 
Description 

Sample Texture 2D At UV Positions 
Sample the given Texture Map at the list of UV positions and return the color at each position in the Color List output. 
Create New Texture 2D Asset 
Create a serialized Texture 2D Asset from a temporary UTexture2D. 
Sample Texture Render Target 2D At UV Positions 
Sample the given Texture Map at the list of UV positions and return the color at each position in Color List output. This function fetches GPU data before sampling, so, depending on your application, it can be inefficient and slow. 
Baking
These functions bake data between a source and target mesh into texture or vertex color data. You can bake various mesh data such as normals, curvature, ambient occlusion, opacity map, and subsurface color map. There is also the ability to specify type of filtering to apply.
Node Name 
Description 

Bake Texture 
Creates textures for the Target Mesh from data sampled in the Source Mesh. 
Bake Vertex 
Populates the vertex colors in the Target Mesh with the results of the baking properties of the given Source Mesh. 
Bake Texture From Render Captures 
Bakes textures for a target mesh from render captures. 
UV
You use these functions to manipulate the UVs of a mesh.
Node Name 
Description 

Get Num UV Channels 
Gets the number of UV Channels on a mesh. 
Set Num UV Channels 
Sets the number of UV Channels on a mesh. 
Get UV Set Bounding Box 
Gets the 2D bounding box of all UVs in a UV Channel. 
Copy UV Channel 
Replaces target UV Channel with values from source UV Channel. 
Translate Mesh UVs 
Applies 2D Translation to all UVs, or a subset of UVs if you provide a Selection, in the UVSet Index. 
Scale Mesh UVs 
Applies 2D Scale to all UVs, or a subset of UVs if you provide a Selection, in the UVSet Index. 
Rotate Mesh UVs 
Apples 2D Rotation to all UVs, or a subset of UVs if you provide a Selection, in the UVSet Index. 
Recompute Mesh UVs 
Recomputes UVs for a Mesh based on different types of welldefined UV islands, such as existing UV islands, PolyGroups, or the Selection input. 
Repack Mesh UVs 
Packs the existing UV islands into standard UV space. 
Set Mesh UVs From Planar Projection 
Using Planar projection, set UVs for an entire mesh or a subset you define by the Selection input. 
Set Mesh UVs From Box Projection 
Using Box Projection, set UVs for an entire mesh or a subset you define by the Selection input. 
Set Mesh UVs From Cylinder Projection 
Using Cylinder Projection, set UVs for an entire mesh or a subset you define by the Selection input. 
Auto Generate Patch Builder Mesh UVs 
Computes new UVs using PatchBuilder method, and optionally pack. 
Auto Generate X Atlas Mesh UVs 
Computes new UVs using XAtlas, and optionally packs. 
Get Mesh UVSize Info 
Computes information about dimensions and areas for a UV Channel of a Mesh, with an optional mesh selection. 
Get Mesh Per Vertex UVs 
Gets a list of single vertex UVs for each mesh vertex in the Target Mesh, derived from the specified UV Overlay. 
Copy Mesh UV Channel To Mesh 
Copies the 2D UVs from the given UV Channel Index in Copy From Mesh to the 3D vertex positions in Copy To UV Mesh. PolyGroup IDs and Material IDs are preserved in the UV Mesh. 
Copy Mesh To Mesh UV Channel 
Transfers the 3D vertex positions and triangles of Copy From UVMesh to the given UV Channel identified by To UV Channel Index of Copy To Mesh. The 3D positions (X,Y,Z) will be copied as UV positions (X,Y). 
Compute Mesh Local UV Param 
Compute local UV parameterization on Target Mesh vertices around the given CenterPoint / Triangle. This method uses a Discrete Exponential Map parameterization, which unwraps the mesh locally based on geodesic distances and angles. The Center Point will have a UV value (0,0), and the computed vertex UVs will be such that 
PolyGroup
Functions for manipulating PolyGroups of a mesh. PolyGroups are pertriangle integers that implicitly define regions and patches of triangles in the modeling tools and some Geometry Script operations. However, a PolyGroup layer is ultimately a pertriangle number, and you can use it for any other purpose. To learn more about PolyGroups see, Understanding PolyGroups.
Node Name 
Description 

Get Has PolyGroups 
Returns true if the mesh has a standard PolyGroup Layer. 
Enable PolyGroups 
Enables standard PolyGroup Layer on a Mesh. 
Get Num Extended PolyGroup Layers 
Returns the count of extended PolyGroup Layers. Note that extended PolyGroup Layers are not yet fully supported by all operations or modeling tools. 
Set Num Extended PolyGroup Layers 
Sets the number of extended PolyGroup Layers on a Mesh. 
Clear PolyGroups 
Resets the triangle PolyGroup assignments to a constant value for a given PolyGroup Layer. 
Copy PolyGroups Layer 
Copies PolyGroups from one layer to another. 
Convert UV Islands To PolyGroups 
Creates and assigns a new PolyGroup for each disconnected UV island of a Mesh. 
Convert Components To PolyGroups 
Creates and assigns a new PolyGroup for each disconnected component of a Mesh. 
Compute PolyGroups From Angle Threshold 
Sets PolyGroups by partitioning the mesh based on an edge crease/openingangle. 
Compute PolyGroups From Polygon Detection 
Identifies polygons and assigns PolyGroup IDs. 
Bone Weight
These functions calculate and manipulate bone weights, also known as skin weights. Bone weights determine a bone's transformation influence on a set of vertices. You can also get information about the skeleton stored in the dynamic mesh. This information is onetoone with the Skeletal Mesh skeleton after you convert to dynamic mesh through the Copy Mesh From Skeletal Mesh node.
Node 
Description 

Mesh Has Bone Weights 
Check whether the Target Tesh has a pervertex Bone Weight attribute set. 
Mesh Create Bone Weights 
Create a new Bone Weights attribute on the Target Mesh, if it does not already exist. If it does exist, and 
Get Max Bone Weight Index 
Determine the largest Bone Weight index that exists on the mesh. 
Get Vertex Bone Weights 
Return an array of Bone Weight at a given vertex of the Target Mesh. 
Get Largest Vertex Bone Weight 
Return the Bone Weight of the maximum weight at a given vertex of the Target Mesh. 
Set Vertex Bone Weights 
Set the Bone Weight at a given vertex of the Target Mesh. 
Set All Vertex Bone Weights 
Set all vertices of the Target Mesh to the given Bone Weights. 
Compute Smooth Bone Weights 
Computes a smooth skin binding for the given mesh to the skeleton provided. 
Transfer Bone Weights From Mesh 
Transfer the bone weights from the SourceMesh to the TargetMesh. Assumes that the meshes are aligned. Otherwise, use the Transform Mesh geometry script function to align them. 
Copy Bones From Mesh 
Copy the bone attributes (skeleton) from the Source Mesh to the Target Mesh. 
Discard Bones From Mesh 
Discard the bone attributes (skeleton) from the Target Mesh. 
Get Bone Index 
Get the index of the bone with the given name. 
Get Root Bone Name 
Get the name of the root bone. 
Get Bone Children 
Get the information about the children of the bone. 
Get All Bones Info 
Get an array of bones representing the skeleton. Each entry contains information about the bone. 
Get Bone Info 
Get the index of the bone with the given name. 
Mesh Geometric Queries
Functions for highlevel geometric queries of a mesh.
Node Name 
Description 

Get Mesh Bounding Box 
Computes the bounding box of the mesh vertices. 
Get Mesh Volume Area 
Computes the volume and area of the mesh. 
Get Is Closed Mesh 
Returns true if the mesh is closed, such as no topological boundary edges. 
Get Num Open Border Loops 
Returns the number of open border loops, such as "holes" in the mesh. 
Get Num Open Border Edges 
Returns the number of topological boundary edges in the mesh. 
Get Num Connected Components 
Returns the number of separate connectedcomponents in the mesh, such as "triangle patches" connected by shared edges. 
Compute Mesh Convex Hull 
Computes the Convex Hull of a given Mesh, or part of the mesh you define by the Selection input, and returns in a separate mesh. 
Compute Mesh Swept Hull 
Computes a 2D swepthull of the input mesh and returns in a separate mesh. 
Compute Mesh Convex Decomposition 
Computes a Convex Hull Decomposition of the given Target Mesh. Assuming more than one hull is requested, multiple hulls will be returned that attempt to approximate the mesh. There is no guarantee that the entire mesh is contained in the hulls. 
Get Mesh Volume Area Center 
Computes the volume, area, and centerofmass of the mesh. 
Mesh Geodesic
These functions compute the shortest given path on a mesh surface.
Node 
Description 

Get Shortest Vertex Path 
Computes a vertex list that represents the shortest path constrained to travel along mesh triangle edges between the prescribed start and end vertex. This can fail if the Start and End points are within separate connected components of the mesh. 
Get Shortest Surface Path 
Computes a polypath that represents the shortest mesh surface path between two prescribed points on the provided mesh.This can fail if the Start and End points are within separate connected components of the mesh.

Create Surface Path 
Computes a polypath that represents a "straight" surface path starting at the prescribed point on the mesh, and continuing in the indicated direction until reaching the requested path length or encountering a mesh boundary, whichever comes first.

Simple Polygon
A simple 2D polygon is a closed polygon with no holes. You can use these functions to call and manipulate simple polygons.
Node 
Description 

Get Polygon Vertex Count 
Returns the number of vertices in a simple polygon. 
Get Polygon Vertex 
Returns the specified vertex of a simple polygon. Vertex Index loops around, that is, 1 gives the last vertex in the polygon. If the polygon has no vertices, it returns the zero vector. 
Set Polygon Vertex 
Set the specified vertex of a simple polygon. Vertex Index loops around, that is, 1 gives the last vertex in the polygon. Does nothing if the polygon has no vertices. 
Add Polygon Vertex 
Set the specified vertex of a simple polygon. Returns the index of the added vertex. 
Get Polygon Tangent 
Returns a vertex's tangent of a simple polygon. Vertex Index loops around, that is, 1 gives the tangent of the last vertex in the polygon. If the polygon has no vertices, it returns the zero vector. 
Get Polygon Arc Length 
Returns the arc length of a simple polygon. 
Get Polygon Area 
Returns the area enclosed by a simple polygon. 
Get Polygon Bounds 
Returns the bounding box of a simple polygon. 
Convert Spline To Polygon 
Sample positions from a 
Simple Polygon To Array Of Vector 
Returns an array of 3D vectors with the polygon vertex locations, with Z coordinate set to zero. 
Simple Polygon To Array Of Vector2D 
Returns an array of 2D vectors with the polygon vertex locations. 
Array Of Vector To Simple Polygon 
Returns a polygon created from an array of 3D position vectors, ignoring the Z coordinate. 
Array Of Vector2D To Simple Polygon 
Returns a polygon created from an array of 2D position vectors. 
Polygon List
A polygon list includes a list of general polygons, which may have holes. You can use these functions to call and edit polygons in a polygon list.
Node 
Description 

Get Polygon Vertex Count 
Returns the number of vertices in a polygon's outer shape, if Hole Index is 1, or in the specified inner hole. Returns 0 for invalid polygon or hole indices. 
Get Polygon Vertex 
Returns the specified vertex of a polygon — either of the outer polygon, if Hole Index is 1, or specified inner hole.Vertex are the zero vector for invalid polygon or hole indices, or if the polygon is empty. Vertex Index will loop. 
Get Polygon Count 
Returns the number of polygons in the Polygon List. 
Get Polygon Hole Count 
Returns the number of holes in a polygon. Returns zero for an invalid Polygon Index. 
Get Polygon Vertices 
Returns the vertices of a polygon — either of the outer polygon, if Hole Index is 1, or specified inner hole. Out Vertices are empty for invalid polygon or hole indices. 
Get Polygon Area 
Returns the area enclosed by a polygon. Returns zero for an invalid Polygon Index. 
Get Polygon Bounds 
Returns the bounding box of a polygon. Returns an empty, invalid box for an invalid Polygon Index. 
Get Simple Polygon 
Returns a specified simple polygon from a polygon list — either the outer polygon, if Hole Index is 1, or specified inner hole. Polygon are empty for invalid polygon or hole indices. 
Get Polygon List Area 
Returns the area enclosed by a polygon. 
Get Polygon List Bounds 
Returns the bounding box of a polygon. 
Create Polygon List From Single Polygon 
Create a polygon list of a single polygon, with optional holes. 
Add Polygon To List 
Add Polygon to a polygon list, with optional holes. Returns index of the added polygon. 
Create Polygon List From Simple Polygons 
Create a Polygon List from an array of Simple Polygons. 
Append Polygon List 
Add the polygons in Polygons to Append to Polygon List. 
Polygons Union 
Compute union of all polygons in Polygon List. Also resolves selfintersections within each polygon. 
Polygons Difference 
Compute difference of Polygon List and Polygons to Subtract. 
Polygons Intersection 
Compute intersection of Polygon List and Polygons to Intersect. 
Polygons Exclusive Or 
Compute exclusive or of Polygon List and Polygons to Exclusive Or. 
Polygons Offset 
Apply a single offset to a list of closed polygons. 
Polygons Offsets 
Apply two offsets in sequence to a list of closed polygons. 
Polygons Morphology Open 
Apply a morphological open operator to a list of closed polygons — first offsetting by Offset, then by +Offset. If Offset is negative, this instead functions as a close operation. 
Polygons Morphology Close 
Apply a morphological close operator to a list of closed polygons — first offsetting by +Offset, then by Offset. If Offset is negative, this instead functions as an open operation. 
Create Polygons From Path Offset 
Apply an offset to a single open 2D path, generating closed polygons as a result. 
Poly Path
These functions perform poly path manipulations. A poly path is a path defined by an ordering of vertices.
Node Name 
Description 

Get Poly Path Num Vertices 
Returns the number of vertices in the poly path 
Get Poly Path Last Index 
Returns the index of the last vertex in the poly path. 
Get Poly Path Vertex 
Returns the 3D location of the specified vertex. 
Get Poly Path Tangent 
Returns the local tangent vector of the poly path at the specified vertex index. 
Get Poly Path Arc Length 
Returns the length of the poly path. 
Get Nearest Vertex Index 
Returns the index of the nearest poly path vertex to the specified point in 3D. 
Flatten To 2D On Axis 
Creates a 2D flatten copy of the path, by dropping the given axis and using the other two coordinates as the new X, Y coordinates. 
Convert Spline To Poly Path 
Samples the positions from a USplineComponent into a Poly Path, based on the given Sampling Options. 
Convert Poly Path To Array 
Populates an array of 3D vectors with the poly path vertex locations. 
Convert Array To Poly Path 
Creates a poly path from an array of 3D position vectors. 
Convert Poly Path To Array Of Vector 2D 
Creates an array of 2D Vectors with the poly path vertex locations projected onto the XY plane. 
Convert Array Of Vector 2D To Poly Path 
Creates a poly path from an array of 2D position vectors. The Zcoordinate of the corresponding Poly Path vertices is zero. 
Create Circle Path 3D 
Creates a closed circle around the origin on the XY plane, then is repositioned by the Transform input. 
Create Circle Path 2D 
Creates a closed circle on the XY plane around the given Center. For closed paths, the end vertex is not a duplicate of the start vertex. 
Create Arc Path 3D 
Creates an open arc around the origin on the XY plane, then is repositioned by the Transform input. 
Create Arc Path 2D 
Creates an open arc on the XY plane around the given Center. 
Mesh Comparisons
Functions for comparing two meshes. These nodes do not modify either mesh through their usage.
Node Name 
Description 

Is Same Mesh As 
Returns true if the two input meshes are equivalent under the comparisons defined by the input options. 
Measure Distances Between Meshes 
Measures the min/max and average closestpoint distances between two meshes. 
Is Intersecting Mesh 
Returns true if the two input meshes (with optional transforms) are geometrically intersecting. 
BVH & Spatial Queries
These functions create and query a Bounding Volume Hierarchy (BVH) object for a mesh.
Node Name 
Description 

Build BVH For Mesh 
Builds a BVH object for a mesh that can be used by Is BVH Valid For Mesh, Rebuild BVH for Mesh, Find Nearest Point On Mesh, Find Nearest Ray Intersection With Mesh, and Is Point Inside Mesh nodes. The function returns a Geometry Script dynamic mesh BVH struct. 
Is BVH Valid For Mesh 
Checks if the BVH object can still be used with the Mesh — it generally returns false if the mesh has been changed. 
Rebuild BVH For Mesh 
Rebuilds the BVH object for the mesh inplace, which can reduce memory allocations, compared to building a new BVH. 
Find Nearest Point On Mesh 
Finds the nearest point on the mesh/BVH to a given 3D point. 
Find Nearest Ray Intersection With Mesh 
Finds the nearest intersection of a 3D ray with the mesh or BVH. 
Is Point Inside Mesh 
Tests if a point is inside the mesh/BVH using the Fast Winding Number query. 
Utilities
These helper functions are useful in Geometry Script mesh processing and procedural generators.
Node Name 
Description 

Create Dynamic Mesh Pool 
Creates a new dynamic mesh pool object. 
Create Unique New Asset Path Name 
Create a new unique asset name given a base path and base asset name, which is useful with functions such as Create New Static Mesh Asset From Mesh. This node only works in the Editor. 
Get Mesh Info String 
Returns a debug string that contains mesh statistics and other information. 
Sample Spline To Transforms 
Sample a USplineComponent into a list of FTransforms, based on the given Sampling Options. 
Glossary
Term 
Definition 

Overlay 
A data structure representing a type of vertex data applied to a mesh.These types include: vertex color, normal, tangent, and UV. Multiple values of the specified type can be stored at a single vertex. In such cases, depending on the type, one of the following occurs: the last value is used, the values are averaged, or an arbitrary value is used. 
Onering 
The neighboring vertices of the selected vertex, connected by an edge.

UV Set 
Contains the UV coordinates of a mesh, also referred to as the UV Channel. You can use multiple UV Channels to represent different UV maps. 
Extents 
The halfdimensions of a box, measured along the three axes. They are used to determine how much to extend from a center point. A center point, C, and Extent, E, results in a box with a bottomleftnear corner at 