R/tour-reactives.R

In sa-lee/liminal: Multivariate Data Visualization with Tours and Embeddings

# Reactives for manipulationg a given tour path

#' @importFrom shiny reactive invalidateLater
#' @noRd
rct_half_range <- function(rct_zoom, half_range) {
  shiny::reactive({
    res <- rct_zoom()
    res <- unlist(res)
    if (length(res)) {
      return(max(abs(res)))
    }
    return(half_range)
  })
}


rct_tour <- function(plan, tour_data, tour_path, selections, aps = 1, fps = 8) {
  current <- plan(0)
  shiny::reactive({
    # required as of tourr 0.6.0
    record <- dplyr::tibble(
      basis = list(), index_val = numeric(),
      info = character(), method = character(), alpha = numeric(),
      tries = numeric(), loop = numeric()
    )

    play <- selections[["do_tour"]]

    play <- current$step >= 0 && play
    if (play) {
      current <<- plan(aps / fps)
      selections[["proj"]] <- current$proj
      shiny::invalidateLater(1000 * aps / fps)
    }

    restart <- selections[["force_restart"]]

    if (restart) {
      plan <<- tourr::new_tour(tour_data, tour_path)
      current <<- plan(0)
      selections[["proj"]] <- current$proj
      selections[["force_restart"]] <- FALSE
    }

    current
  })
}