trans3d              package:grDevices              R Documentation

3D to 2D Transformation for Perspective Plots

Description:

     Projection of 3-dimensional to 2-dimensional points using a 4x4
     viewing transformation matrix.  Mainly for adding to perspective
     plots such as 'persp'.

Usage:

     trans3d(x,y,z, pmat)

Arguments:

 x, y, z: numeric vectors of equal length, specifying points in 3D
          space.

    pmat: a 4 x 4 _viewing transformation matrix_, suitable for
          projecting the 3D coordinates (x,y,z) into the 2D plane using
          homogeneous 4D coordinates (x,y,z,t); such matrices are
          returned by 'persp()'.

Value:

     a list with two components 

     x,y: the projected 2d coordinates of the 3d input '(x,y,z)'.

See Also:

     'persp'

Examples:

     ## See  help(persp) {after attaching the 'graphics' package}
     ##      -----------

