R/dpv-funcs.R

In LCBC-UiO/ggsegExtra: Extra Utilities for the 'ggseg' and 'ggseg3d' Plotting Tools

# dpv-functions ----

#' Write DPV file
#' 
#' write a data-per-vertex file,
#' and ascii-format text-file
#' based on vertices and faces.
#'
#' @param path path to file
#' @param vertices object with vertices
#' @param faces object with faces
#' @noRd
# #' @export
write_dpv <- function(path, vertices, faces){
  # face index start at 0
  if(min(faces) == 1) faces <- faces - 1
  
  # Add 0-col to both
  vertices <- cbind(vertices, r = rep(0, nrow(vertices)))
  faces <- cbind(faces, r = rep(0, nrow(faces)))
  
  # Make every row a single string
  vertices <- within(vertices,  l <- sprintf(paste('%f %f %f %g'), x, y, z, r))
  faces <- within(faces,  l <- sprintf(paste('%g %g %g %g'), i, j, k, r))
  
  # Write to the disk
  file_content <- c(
    "#!ascii",
    sprintf('%g %g', nrow(vertices), nrow(faces)),
    vertices$l,
    faces$l
  )
  
  con <- file(path)
  on.exit(close(con))
  writeLines(file_content, con)
}

#' Read dpv file
#' 
#' Read in data-per-vertex file, which is
#' usually a file made by for instance \code{\link{surf2asc}},
#' \code{\link{curv2asc}}, \code{\link{curvnf2asc}}
#'
#' @param path path to dpv file
#' @noRd
#' @return list of vertices and faces
#' @importFrom utils read.table
read_dpv <- function(path){
  
  k <- readLines(path)
  
  ns <- strsplit(k[2], " ")[[1]]
  names(ns) <- c("nvertices", "nfaces")  
  
  k <- read.table(path, skip = 2)
  
  vertices <- k[1:ns["nvertices"],]
  row.names(vertices) = NULL
  
  faces <- k[ns["nvertices"]:length(k),]
  row.names(faces) = NULL
  
  return(list(vertices = vertices,
              faces = faces))
}

#' Check if dpv is facewise
#'
#' @param dpx vertex or face data
#' @param surface surface vertex and face list
#' @template verbose 
#' @noRd
is_facewise <- function(dpx, surface, verbose = TRUE){

  nX = nrow(dpx)
  nV = nrow(surface$vertices)
  nF = nrow(surface$faces)
  
  # Verify if this is facewise or vertexwise data
  if(nX == nV){
    if(verbose) cat('Working with vertexwise data.\n')
    return(FALSE)
  }else if(nX == nF){
    if(verbose) cat('Working with facewise data.\n');
    return(TRUE)
  } else{
    stop('The annot-data does not match the surface.\n', call. = FALSE)
  }
}