These functions are intended to replace common low level traditional graphics functions, primarily for use in panel functions. The originals can not be used (at least not easily) because lattice panel functions need to use grid graphics. Low level drawing functions in grid can be used directly as well, and is often more flexible. These functions are provided for convenience and portability.
lplot.xy(xy, type, pch, lty, col, cex, lwd,
         font, fontfamily, fontface,
         col.line, col.symbol, alpha, fill,
         origin = 0, …, identifier, name.type)llines(x, ...)
lpoints(x, ...)
ltext(x, ...)
# S3 method for default
llines(x, y = NULL, type = "l",
       col, alpha, lty, lwd, …, identifier, name.type)
# S3 method for default
lpoints(x, y = NULL, type = "p", col, pch, alpha, fill,
        font, fontfamily, fontface, cex, …, identifier, name.type)  
# S3 method for default
ltext(x, y = NULL, labels = seq_along(x),
      col, alpha, cex, srt = 0,
      lineheight, font, fontfamily, fontface,
      adj = c(0.5, 0.5), pos = NULL, offset = 0.5, …, identifier, name.type)  
lsegments(x0, y0, x1, y1, x2, y2,
          col, alpha, lty, lwd,
          font, fontface, …, identifier, name.type)
lrect(xleft, ybottom, xright, ytop,
      x = (xleft + xright) / 2,
      y = (ybottom + ytop) / 2,
      width = xright - xleft,
      height = ytop - ybottom,
      col = "transparent",
      border = "black",
      lty = 1, lwd = 1, alpha = 1,
      just = "center",
      hjust = NULL, vjust = NULL,
      font, fontface,
      …, identifier, name.type)
larrows(x0 = NULL, y0 = NULL, x1, y1, x2 = NULL, y2 = NULL,
        angle = 30, code = 2, length = 0.25, unit = "inches",
        ends = switch(code, "first", "last", "both"),
        type = "open",
        col = add.line$col,
        alpha = add.line$alpha,
        lty = add.line$lty,
        lwd = add.line$lwd,
        fill = NULL, 
        font, fontface,
        …, identifier, name.type)
lpolygon(x, y = NULL,
         border = "black", col = "transparent", fill = NULL, 
         font, fontface, …, identifier, name.type)
panel.lines(…)
panel.points(…)
panel.segments(…)
panel.text(…)
panel.rect(…)
panel.arrows(…)
panel.polygon(…)
locations. x2 and
    y2 are available for for S compatibility.
determines extent of arrow head.  length specifies the length
    in terms of unit, which can be any valid grid unit as long as
    it doesn't need a data argument.  unit defaults to
    inches, which is the only option in the base version of the
    function, arrows.
arguments
    controlling behaviour.  See respective base functions for details.
    For larrows and panel.larrows, type is either
    "open" or "closed", indicating the type of
    arrowhead.
serves the same function as code, using
    descriptive names rather than integer codes.  If specified, this
    overrides code
graphical
    parameters.  fill applies to points when pch is in
    21:25 and specifies the fill color, similar to the bg
    argument in the base graphics function points. For
    devices that support alpha-transparency, a numeric argument
    alpha between 0 and 1 can controls transparency.  Be careful
    with this, since for devices that do not support alpha-transparency,
    nothing will be drawn at all if this is set to anything other than
    0.
fill, font and fontface are included in
    lrect, larrows, lpolygon, and lsegments
    only to ensure that they are not passed down (as gpar
    does not like them).
for type="h" or type="H", the value to
    which lines drop down.
see rect
finer control over
    rectangles, see grid.rect
extra arguments, passed on to lower level functions as appropriate.
A character string that is prepended to the name of the grob that is created.
A character value indicating whether the name of the grob
    should have panel or strip information added to it.
    Typically either "panel", "strip",
    "strip.left", or "" (for no extra information).
These functions are meant to be grid replacements of the corresponding
  base R graphics functions, to allow existing Trellis code to be used
  with minimal modification.  The functions panel.* are
  essentally identical to the l* versions, are recommended for
  use in new code (as opposed to ported code) as they have more readable
  names.
See the documentation of the base functions for usage. Not all arguments are always supported. All these correspond to the default methods only.