| vf2blocks {ptinpoly} | R Documentation |
Convertor from Vertices-Faces Representation to 3-Block Representation
Description
Converts a polyhedron from the vertices-faces representation to the three-block representation.
Usage
vf2blocks(Vertices,Faces)Arguments
Vertices |
N by 3 matrix containing the XYZ coordinates of N vertices |
Faces |
M by 3 matrix containing indices of vertices defining M faces |
Details
The values in the Face matrix must be integers with values running from 1 to N,
where N is the number of vertices. A value of '1' in this matrix, for example,
represents the 1st vertex, i.e., the vertex defined by the first row in the
matrix Vertices.
This function is the inverse of the blocks2vf function.
Value
Returns a list of three matrices. The first is an M by 3 matrix containing the XYZ coordinates of vertex 1 of the M faces of the polyhedron. The second and third are similarly M by 3 matrices, but contain the XYZ coordinates of vertices 2 and 3 of the faces. See the example below.
Examples
# Load example data.
data(verts)
data(faces)
# Use vf2blocks to convert from vertices-faces representation to 3-block representation.
# Note double square brackets.
blocks = vf2blocks(verts,faces)
block1 = blocks[[1]]
block2 = blocks[[2]]
block3 = blocks[[3]]