a vector of subscripts, that tells where in the overall data, the
selected
x and
y observations originate.
z
z coordinates of all points.
z[subscripts] gives the sets of
z values corresponding to
x and
y.
...
graphical parameters that are passed to
polygon.
By default, the trellis parameter list
wires will be used to control line width (
lwd ),
line type (
lty ) and color (
col ) for the wireframe lines;
the
regions parameters will be used to control color (
col ) of the surface
patches in color draping.
Panel color is
0 (for background) by default,
to cause near surface patches to obscure ones plotted earlier.
The panel function takes care to plot patches in order, from most distant
to nearest the eyepoint.