unreal.MeshDescriptionBase

class unreal.MeshDescriptionBase(outer=None, name='None')

Bases: unreal.Object

Mesh Description Base

C++ Source:

• Module: MeshDescription

• File: MeshDescriptionBase.h

compute_polygon_triangulation(polygon_id) → None

Generates triangles and internal edges for the given polygon

Parameters

polygon_id (PolygonID) –

create_edge(vertex_id0, vertex_id1) → EdgeID

Adds a new edge to the mesh and returns its ID

Parameters

• vertex_id0 (VertexID) –

• vertex_id1 (VertexID) –

Return type

EdgeID

create_edge_with_id(edge_id, vertex_id0, vertex_id1) → None

Adds a new edge to the mesh with the given ID

Parameters

• edge_id (EdgeID) –

• vertex_id0 (VertexID) –

• vertex_id1 (VertexID) –

create_polygon(polygon_group_id) -> (PolygonID, vertex_instance_i_ds=Array(VertexInstanceID), new_edge_i_ds=Array(EdgeID))

Adds a new polygon to the mesh and returns its ID. This will also make any missing edges, and all constituent triangles.

Parameters

polygon_group_id (PolygonGroupID) –

Returns

vertex_instance_i_ds (Array(VertexInstanceID)):

new_edge_i_ds (Array(EdgeID)):

Return type

tuple

create_polygon_group() → PolygonGroupID

Adds a new polygon group to the mesh and returns its ID

Return type

PolygonGroupID

create_polygon_group_with_id(polygon_group_id) → None

Adds a new polygon group to the mesh with the given ID

Parameters

polygon_group_id (PolygonGroupID) –

create_polygon_with_id(polygon_id, polygon_group_id) -> (vertex_instance_i_ds=Array(VertexInstanceID), new_edge_i_ds=Array(EdgeID))

Adds a new polygon to the mesh with the given ID. This will also make any missing edges, and all constituent triangles.

Parameters

• polygon_id (PolygonID) –

• polygon_group_id (PolygonGroupID) –

Returns

vertex_instance_i_ds (Array(VertexInstanceID)):

new_edge_i_ds (Array(EdgeID)):

Return type

tuple

create_triangle(polygon_group_id, vertex_instance_i_ds) -> (TriangleID, new_edge_i_ds=Array(EdgeID))

Adds a new triangle to the mesh and returns its ID. This will also make an encapsulating polygon, and any missing edges.

Parameters

• polygon_group_id (PolygonGroupID) –

• vertex_instance_i_ds (Array(VertexInstanceID)) –

Returns

new_edge_i_ds (Array(EdgeID)):

Return type

Array(EdgeID)

create_triangle_with_id(triangle_id, polygon_group_id, vertex_instance_i_ds)

Adds a new triangle to the mesh with the given ID. This will also make an encapsulating polygon, and any missing edges.

Parameters

• triangle_id (TriangleID) –

• polygon_group_id (PolygonGroupID) –

• vertex_instance_i_ds (Array(VertexInstanceID)) –

Returns

new_edge_i_ds (Array(EdgeID)):

Return type

Array(EdgeID)

create_vertex() → VertexID

Adds a new vertex to the mesh and returns its ID

Return type

VertexID

create_vertex_instance(vertex_id) → VertexInstanceID

Adds a new vertex instance to the mesh and returns its ID

Parameters

vertex_id (VertexID) –

Return type

VertexInstanceID

create_vertex_instance_with_id(vertex_instance_id, vertex_id) → None

Adds a new vertex instance to the mesh with the given ID

Parameters

• vertex_instance_id (VertexInstanceID) –

• vertex_id (VertexID) –

create_vertex_with_id(vertex_id) → None

Adds a new vertex to the mesh with the given ID

Parameters

vertex_id (VertexID) –

delete_edge(edge_id)

Deletes an edge from a mesh

Parameters

edge_id (EdgeID) –

Returns

orphaned_vertices (Array(VertexID)):

Return type

Array(VertexID)

delete_polygon(polygon_id) -> (orphaned_edges=Array(EdgeID), orphaned_vertex_instances=Array(VertexInstanceID), orphaned_polygon_groups=Array(PolygonGroupID))

Deletes a polygon from the mesh

Parameters

polygon_id (PolygonID) –

Returns

orphaned_edges (Array(EdgeID)):

orphaned_vertex_instances (Array(VertexInstanceID)):

orphaned_polygon_groups (Array(PolygonGroupID)):

Return type

tuple

delete_polygon_group(polygon_group_id) → None

Deletes a polygon group from the mesh

Parameters

polygon_group_id (PolygonGroupID) –

delete_triangle(triangle_id) -> (orphaned_edges=Array(EdgeID), orphaned_vertex_instances=Array(VertexInstanceID), orphaned_polygon_groups_ptr=Array(PolygonGroupID))

Deletes a triangle from the mesh

Parameters

triangle_id (TriangleID) –

Returns

orphaned_edges (Array(EdgeID)):

orphaned_vertex_instances (Array(VertexInstanceID)):

orphaned_polygon_groups_ptr (Array(PolygonGroupID)):

Return type

tuple

delete_vertex(vertex_id) → None

Deletes a vertex from the mesh

Parameters

vertex_id (VertexID) –

delete_vertex_instance(vertex_instance_id)

Deletes a vertex instance from a mesh

Parameters

vertex_instance_id (VertexInstanceID) –

Returns

orphaned_vertices (Array(VertexID)):

Return type

Array(VertexID)

empty() → None

Empty the mesh description

get_edge_connected_polygons(edge_id)

Returns the polygons connected to this edge

Parameters

edge_id (EdgeID) –

Returns

out_connected_polygon_i_ds (Array(PolygonID)):

Return type

Array(PolygonID)

get_edge_connected_triangles(edge_id)

Returns reference to an array of triangle IDs connected to this edge

Parameters

edge_id (EdgeID) –

Returns

out_connected_triangle_i_ds (Array(TriangleID)):

Return type

Array(TriangleID)

get_edge_count() → int32

Returns the number of edges

Return type

int32

get_edge_vertex(edge_id, vertex_number) → VertexID

Returns the vertex ID corresponding to one of the edge endpoints

Parameters

• edge_id (EdgeID) –

• vertex_number (int32) –

Return type

VertexID

get_edge_vertices(edge_id)

Returns a pair of vertex IDs defining the edge

Parameters

edge_id (EdgeID) –

Returns

out_vertex_i_ds (Array(VertexID)):

Return type

Array(VertexID)

get_num_edge_connected_polygons(edge_id) → int32

Returns the number of polygons connected to this edge

Parameters

edge_id (EdgeID) –

Return type

int32

get_num_edge_connected_triangles(edge_id) → int32

Returns the number of triangles connected to this edge

Parameters

edge_id (EdgeID) –

Return type

int32

get_num_polygon_group_polygons(polygon_group_id) → int32

Returns the number of polygons in this polygon group

Parameters

polygon_group_id (PolygonGroupID) –

Return type

int32

get_num_polygon_internal_edges(polygon_id) → int32

Return the number of internal edges in this polygon

Parameters

polygon_id (PolygonID) –

Return type

int32

get_num_polygon_triangles(polygon_id) → int32

Return the number of triangles which comprise this polygon

Parameters

polygon_id (PolygonID) –

Return type

int32

get_num_polygon_vertices(polygon_id) → int32

Returns the number of vertices this polygon has

Parameters

polygon_id (PolygonID) –

Return type

int32

get_num_vertex_connected_edges(vertex_id) → int32

Returns number of edges connected to this vertex

Parameters

vertex_id (VertexID) –

Return type

int32

get_num_vertex_connected_polygons(vertex_id) → int32

Returns the number of polygons connected to this vertex

Parameters

vertex_id (VertexID) –

Return type

int32

get_num_vertex_connected_triangles(vertex_id) → int32

Returns number of triangles connected to this vertex

Parameters

vertex_id (VertexID) –

Return type

int32

get_num_vertex_instance_connected_polygons(vertex_instance_id) → int32

Returns the number of polygons connected to this vertex instance.

Parameters

vertex_instance_id (VertexInstanceID) –

Return type

int32

get_num_vertex_instance_connected_triangles(vertex_instance_id) → int32

Returns the number of triangles connected to this vertex instance

Parameters

vertex_instance_id (VertexInstanceID) –

Return type

int32

get_num_vertex_vertex_instances(vertex_id) → int32

Returns number of vertex instances created from this vertex

Parameters

vertex_id (VertexID) –

Return type

int32

get_polygon_adjacent_polygons(polygon_id)

Populates the passed array with adjacent polygons

Parameters

polygon_id (PolygonID) –

Returns

out_polygon_i_ds (Array(PolygonID)):

Return type

Array(PolygonID)

get_polygon_count() → int32

Returns the number of polygons

Return type

int32

get_polygon_group_count() → int32

Returns the number of polygon groups

Return type

int32

get_polygon_group_polygons(polygon_group_id)

Returns the polygons associated with the given polygon group

Parameters

polygon_group_id (PolygonGroupID) –

Returns

out_polygon_i_ds (Array(PolygonID)):

Return type

Array(PolygonID)

get_polygon_internal_edges(polygon_id)

Populate the provided array with a list of edges which are internal to the polygon, i.e. those which separate

constituent triangles.

Parameters

polygon_id (PolygonID) –

Returns

out_edge_i_ds (Array(EdgeID)):

Return type

Array(EdgeID)

get_polygon_perimeter_edges(polygon_id)

Returns the edges which form the polygon perimeter

Parameters

polygon_id (PolygonID) –

Returns

out_edge_i_ds (Array(EdgeID)):

Return type

Array(EdgeID)

get_polygon_polygon_group(polygon_id) → PolygonGroupID

Return the polygon group associated with a polygon

Parameters

polygon_id (PolygonID) –

Return type

PolygonGroupID

get_polygon_triangles(polygon_id)

Return reference to an array of triangle IDs which comprise this polygon

Parameters

polygon_id (PolygonID) –

Returns

out_triangle_i_ds (Array(TriangleID)):

Return type

Array(TriangleID)

get_polygon_vertex_instances(polygon_id)

Returns reference to an array of VertexInstance IDs forming the perimeter of this polygon

Parameters

polygon_id (PolygonID) –

Returns

out_vertex_instance_i_ds (Array(VertexInstanceID)):

Return type

Array(VertexInstanceID)

get_polygon_vertices(polygon_id)

Returns the vertices which form the polygon perimeter

Parameters

polygon_id (PolygonID) –

Returns

out_vertex_i_ds (Array(VertexID)):

Return type

Array(VertexID)

get_triangle_adjacent_triangles(triangle_id)

Returns the adjacent triangles to this triangle

Parameters

triangle_id (TriangleID) –

Returns

out_triangle_i_ds (Array(TriangleID)):

Return type

Array(TriangleID)

get_triangle_count() → int32

Returns the number of triangles

Return type

int32

get_triangle_edges(triangle_id)

Returns the edges which define this triangle

Parameters

triangle_id (TriangleID) –

Returns

out_edge_i_ds (Array(EdgeID)):

Return type

Array(EdgeID)

get_triangle_polygon(triangle_id) → PolygonID

Get the polygon which contains this triangle

Parameters

triangle_id (TriangleID) –

Return type

PolygonID

get_triangle_polygon_group(triangle_id) → PolygonGroupID

Get the polygon group which contains this triangle

Parameters

triangle_id (TriangleID) –

Return type

PolygonGroupID

get_triangle_vertex_instance(triangle_id, index) → VertexInstanceID

Get the specified vertex instance by index

Parameters

• triangle_id (TriangleID) –

• index (int32) –

Return type

VertexInstanceID

get_triangle_vertex_instances(triangle_id)

Get the vertex instances which define this triangle

Parameters

triangle_id (TriangleID) –

Returns

out_vertex_instance_i_ds (Array(VertexInstanceID)):

Return type

Array(VertexInstanceID)

get_triangle_vertices(triangle_id)

Returns the vertices which define this triangle

Parameters

triangle_id (TriangleID) –

Returns

out_vertex_i_ds (Array(VertexID)):

Return type

Array(VertexID)

get_vertex_adjacent_vertices(vertex_id)

Returns the vertices adjacent to this vertex

Parameters

vertex_id (VertexID) –

Returns

out_adjacent_vertex_i_ds (Array(VertexID)):

Return type

Array(VertexID)

get_vertex_connected_edges(vertex_id)

Returns reference to an array of Edge IDs connected to this vertex

Parameters

vertex_id (VertexID) –

Returns

out_edge_i_ds (Array(EdgeID)):

Return type

Array(EdgeID)

get_vertex_connected_polygons(vertex_id)

Returns the polygons connected to this vertex

Parameters

vertex_id (VertexID) –

Returns

out_connected_polygon_i_ds (Array(PolygonID)):

Return type

Array(PolygonID)

get_vertex_connected_triangles(vertex_id)

Returns the triangles connected to this vertex

Parameters

vertex_id (VertexID) –

Returns

out_connected_triangle_i_ds (Array(TriangleID)):

Return type

Array(TriangleID)

get_vertex_count() → int32

Returns the number of vertices

Return type

int32

get_vertex_instance_connected_polygons(vertex_instance_id)

Returns the polygons connected to this vertex instance

Parameters

vertex_instance_id (VertexInstanceID) –

Returns

out_connected_polygon_i_ds (Array(PolygonID)):

Return type

Array(PolygonID)

get_vertex_instance_connected_triangles(vertex_instance_id)

Returns reference to an array of Triangle IDs connected to this vertex instance

Parameters

vertex_instance_id (VertexInstanceID) –

Returns

out_connected_triangle_i_ds (Array(TriangleID)):

Return type

Array(TriangleID)

get_vertex_instance_count() → int32

Returns the number of vertex instances

Return type

int32

get_vertex_instance_for_polygon_vertex(polygon_id, vertex_id) → VertexInstanceID

Return the vertex instance which corresponds to the given vertex on the given polygon, or INDEX_NONE

Parameters

• polygon_id (PolygonID) –

• vertex_id (VertexID) –

Return type

VertexInstanceID

get_vertex_instance_for_triangle_vertex(triangle_id, vertex_id) → VertexInstanceID

Return the vertex instance which corresponds to the given vertex on the given triangle, or INDEX_NONE

Parameters

• triangle_id (TriangleID) –

• vertex_id (VertexID) –

Return type

VertexInstanceID

get_vertex_instance_pair_edge(vertex_instance_id0, vertex_instance_id1) → EdgeID

Returns the edge ID defined by the two given vertex instance IDs, if there is one; otherwise INDEX_NONE

Parameters

• vertex_instance_id0 (VertexInstanceID) –

• vertex_instance_id1 (VertexInstanceID) –

Return type

EdgeID

get_vertex_instance_vertex(vertex_instance_id) → VertexID

Returns the vertex ID associated with the given vertex instance

Parameters

vertex_instance_id (VertexInstanceID) –

Return type

VertexID

get_vertex_pair_edge(vertex_id0, vertex_id1) → EdgeID

Returns the edge ID defined by the two given vertex IDs, if there is one; otherwise INDEX_NONE

Parameters

• vertex_id0 (VertexID) –

• vertex_id1 (VertexID) –

Return type

EdgeID

get_vertex_position(vertex_id) → Vector

Gets a vertex position

Parameters

vertex_id (VertexID) –

Return type

Vector

get_vertex_vertex_instances(vertex_id)

Returns reference to an array of VertexInstance IDs instanced from this vertex

Parameters

vertex_id (VertexID) –

Returns

out_vertex_instance_i_ds (Array(VertexInstanceID)):

Return type

Array(VertexInstanceID)

is_edge_internal(edge_id) → bool

Determine whether a given edge is an internal edge between triangles of a polygon

Parameters

edge_id (EdgeID) –

Return type

bool

is_edge_internal_to_polygon(edge_id, polygon_id) → bool

Determine whether a given edge is an internal edge between triangles of a specific polygon

Parameters

• edge_id (EdgeID) –

• polygon_id (PolygonID) –

Return type

bool

is_edge_valid(edge_id) → bool

Returns whether the passed edge ID is valid

Parameters

edge_id (EdgeID) –

Return type

bool

is_empty() → bool

Return whether the mesh description is empty

Return type

bool

is_polygon_group_valid(polygon_group_id) → bool

Returns whether the passed polygon group ID is valid

Parameters

polygon_group_id (PolygonGroupID) –

Return type

bool

is_polygon_valid(polygon_id) → bool

Returns whether the passed polygon ID is valid

Parameters

polygon_id (PolygonID) –

Return type

bool

is_triangle_part_of_ngon(triangle_id) → bool

Determines if this triangle is part of an n-gon

Parameters

triangle_id (TriangleID) –

Return type

bool

is_triangle_valid(triangle_id) → bool

Returns whether the passed triangle ID is valid

Parameters

triangle_id (TriangleID) –

Return type

bool

is_vertex_instance_valid(vertex_instance_id) → bool

Returns whether the passed vertex instance ID is valid

Parameters

vertex_instance_id (VertexInstanceID) –

Return type

bool

is_vertex_orphaned(vertex_id) → bool

Returns whether a given vertex is orphaned, i.e. it doesn’t form part of any polygon

Parameters

vertex_id (VertexID) –

Return type

bool

is_vertex_valid(vertex_id) → bool

Returns whether the passed vertex ID is valid

Parameters

vertex_id (VertexID) –

Return type

bool

reserve_new_edges(number_of_new_edges) → None

Reserves space for this number of new edges

Parameters

number_of_new_edges (int32) –

reserve_new_polygon_groups(number_of_new_polygon_groups) → None

Reserves space for this number of new polygon groups

Parameters

number_of_new_polygon_groups (int32) –

reserve_new_polygons(number_of_new_polygons) → None

Reserves space for this number of new polygons

Parameters

number_of_new_polygons (int32) –

reserve_new_triangles(number_of_new_triangles) → None

Reserves space for this number of new triangles

Parameters

number_of_new_triangles (int32) –

reserve_new_vertex_instances(number_of_new_vertex_instances) → None

Reserves space for this number of new vertex instances

Parameters

number_of_new_vertex_instances (int32) –

reserve_new_vertices(number_of_new_vertices) → None

Reserves space for this number of new vertices

Parameters

number_of_new_vertices (int32) –

reverse_polygon_facing(polygon_id) → None

Reverse the winding order of the vertices of this polygon

Parameters

polygon_id (PolygonID) –

set_polygon_polygon_group(polygon_id, polygon_group_id) → None

Sets the polygon group associated with a polygon

Parameters

• polygon_id (PolygonID) –

• polygon_group_id (PolygonGroupID) –

set_polygon_vertex_instances(polygon_id, vertex_instance_i_ds) → None

Set the vertex instance at the given index around the polygon to the new value

Parameters

• polygon_id (PolygonID) –

• vertex_instance_i_ds (Array(VertexInstanceID)) –

set_vertex_position(vertex_id, position) → None

Sets a vertex position

Parameters

• vertex_id (VertexID) –

• position (Vector) –