MeshIndexedTriangles

class cee.geo.MeshIndexedTriangles()

This class implements a Mesh for indexed triangles.

Rather than defining each triangle directly as an array of vertices, an array containing x, y and z values for each unique vertex in the part is defined. Then triangles are defined by arrays of indices that refer to elements of this vertex array. This allows triangles to share vertices, thus reducing the number of vertices, and enabling the computation of smooth shade normals.

Note that while the vertices array contains 3 elements per point (x, y and z), the elements in the indices array are interpreted as vertex indices. For example, if vertices contains 3 vertices A, B and C:

`
vertices = [Ax, Ay, Az, Bx, By, Bz, Cx, Cy, Cz];
`

Then vertex A is at index 0, vertex B and 1 and vertex C at 2. So the triangle containing these vertices would be defined with

`
indices = [0, 1, 2];
`

Constructors

constructor

Accessors

boundingBox
indexArray
primitiveCount
primitiveType
textureCoordinates
vertexArray
vertexCount

Methods

getPrimitiveVertices
rayIntersect
constructPreserveSharpEdges

Constructors

MeshIndexedTriangles.constructor(vertices, indices[, optionalVertexData])

Arguments:

vertices (ArrayLike) – None
indices (ArrayLike) – None
optionalVertexData (OptionalIndexedTriangleVertexData) – optional None

Creates an indexed triangle mesh with the given vertices and indices.

Return type:: MeshIndexedTriangles

Accessors

cee.geo.boundingBox()

Returns a copy of the BoundingBox of the mesh

Return type:: BoundingBox

cee.geo.indexArray()

A readonly array containing the indices of the mesh

Return type:: ArrayLike <number>

cee.geo.primitiveCount()

The number of primitives in the mesh.

Return type:: number

cee.geo.primitiveType()

The type of primitives that are used in the mesh.

Return type:: MeshPrimitiveType

cee.geo.textureCoordinates()

A readonly array containing the 2d texture coordinates of the mesh

Return type:: ArrayLike <number>

cee.geo.vertexArray()

A readonly array containing the vertices of the mesh

Return type:: ArrayLike <number>

cee.geo.vertexCount()

The number of vertices in the mesh.

Return type:: number

Methods

getPrimitiveVertices

MeshIndexedTriangles.getPrimitiveVertices(primitiveIndex)

Arguments:

primitiveIndex (number) – None

Returns a copy of the vertex indices of a given primitive.

Return type:: [Vec3]

rayIntersect

MeshIndexedTriangles.rayIntersect(ray[, hitItem])

Arguments:

ray (Ray) – None
hitItem (MeshHitItem) – optional None

Performs picking on the mesh.

If a primitive was hit, the function returns true and populates the passed hitItem object with information about this primitive. It nothing was hit, returns false.

Return type:: boolean

static constructPreserveSharpEdges

MeshIndexedTriangles.constructPreserveSharpEdges(creaseAngleDegrees, vertices, indices[, optionalVertexData])

Arguments:

creaseAngleDegrees (number) – None
vertices (ArrayLike) – None
indices (ArrayLike) – None
optionalVertexData (OptionalIndexedTriangleVertexData) – optional None

Creates an indexed triangle mesh with the given vertices and indices.

Preserve sharp edges by splitting vertices on edges where the surface normal of the two triangles sharing the edge is more than the given angle (in degrees).

Return type:: MeshIndexedTriangles