R/manual.R

In thomasp85/fawkes: An R Interface to the AxiDraw Plotter

#' Manually control the AxiDraw
#'
#' This function sets up a connection to the AxiDraw and returns an object with
#' methods for directly controlling the movement of the pen plotter.
#'
#' @param units The units that movement is given in. Either `'cm'` or `'in'`.
#' @param options An `axi_options` object. See the documentation for
#' [axi_options()] for all the settings.
#'
#' @note
#' Before and after use it is necessary to call the `connect()`/`disconnect()`
#' methods to signal the start and end of a sequence of instructions.
#'
#' @section Instructions:
#' The following methods are available to the returned object:
#' - `connect()`: Start a connection to the plotter.
#' - `disconnect()`: End a connection to the plotter.
#' - `update_options()`: Change the options of the plotter.
#' - `go_to()`: Move the plotter head to the absolute (x, y) position.
#' - `move_to()`: Move the plotter head to the absolute (x, y) position, raising
#'   the head if not already up.
#' - `line_to()`: Move the plotter head to the absolute (x, y) position, lowering
#'   the head if not already down.
#' - `go_rel()`: Move the plotter head with the relative (x, y) amount.
#' - `move_rel()`: Move the plotter head with the relative (x, y) amount, raising
#'   the head if not already up.
#' - `line_rel()`: Move the plotter head with the relative (x, y) amount, lowering
#'   the head if not already down.
#' - `pen_up()`: Raise the pen head.
#' - `pen_down()`: Lower the pen head.
#'
#' @return An object with the methods given in the *Instructions* section.
#'
#' @export
axi_manual <- function(units = 'cm', options = axi_options()) {
  units <- match.arg(tolower(units), c('cm', 'in'))
  axidraw <- import_axidraw()
  axidraw$interactive()
  axidraw$options$units <- match(units, c('in', 'cm')) - 1L
  axidraw <- set_options(axidraw, options)
  AxiManual$new(axidraw)
}

AxiManual <- R6::R6Class('AxiManual',
  public = list(
    initialize = function(axidraw) {
      private$axidraw <- axidraw
    },
    print = function(...) {
      cat("An AxiDraw connection. See `?axi_manual` for information about its methods\n")
    },
    connect = function() {
      private$axidraw$connect()
      invisible(self)
    },
    disconnect = function() {
      private$axidraw$disconnect()
      invisible(self)
    },
    update_options = function(options) {
      private$axidraw <- set_options(private$axidraw, options)
      private$axidraw$update()
      invisible(self)
    },
    go_to = function(x, y) {
      private$axidraw$goto(x, y)
      invisible(self)
    },
    move_to = function(x, y) {
      private$axidraw$moveto(x, y)
      invisible(self)
    },
    line_to = function(x, y) {
      private$axidraw$lineto(x, y)
      invisible(self)
    },
    go_rel = function(x, y) {
      private$axidraw$go(x, y)
      invisible(self)
    },
    move_rel = function(x, y) {
      private$axidraw$move(x, y)
      invisible(self)
    },
    line_rel = function(x, y) {
      private$axidraw$line(x, y)
      invisible(self)
    },
    pen_up = function() {
      private$axidraw$penup()
      invisible(self)
    },
    pen_down = function() {
      private$axidraw$pendown()
      invisible(self)
    },
    set_pen_color = function(color, ...) {
      invisible(self)
    }
  ),
  private = list(
    axidraw = NULL
  )
)