Triangular face used in deprecated geometry. These are created automatically for all standard geometry types, however if you are building a custom geometry you will have to create them manually.
a — Vertex A index.
b — Vertex B index.
c — Vertex C index.
normal — (optional) Face normal ([page:Vector3 Vector3]) or array of vertex normals.
If a single vector is passed in, this sets [page:.normal], otherwise if an array of three
vectors is passed in this sets [page:.vertexNormals]
color — (optional) Face [page:Color color] or array of vertex [page:Color colors].
If a single vector is passed in, this sets [page:.color], otherwise if an array of three
vectors is passed in this sets [page:.vertexColors]
materialIndex — (optional) which index of an array of materials to associate
with the face.
Vertex A index.
Vertex B index.
Vertex C index.
Face normal - vector showing the direction of the Face3. If calculated automatically, this is the normalized cross product of two edges of the triangle. Default is *(0, 0, 0)*.
Face color - for this to be used a material's [page:Material.vertexColors vertexColors] property must be set to *true*.
Array of 3 [page:Vector3 vertex normals].
Array of 3 vertex colors - for these to be used a material's [page:Material.vertexColors vertexColors] property must be set to *true*.
Material index (points to an index in the associated array of materials). Default is *0*.
Creates a new clone of the Face3 object.
Copy the parameters of another Face3 into this.
[link:https://github.com/mrdoob/three.js/blob/master/src/[path].js src/[path].js]