R/ComputeSaccadeMeasures.R

In sascha2schroeder/popEye: Analysis of eye-tracking data from reading experiments

ComputeSaccadeMeasures <- function(dat, trial, env = parent.frame(n = 2)) {
  
  # trial <- 1
  
  sac <- dat$item[[trial]]$sac
  
  sac$subid <- env$subid
  sac$trialid <- dat$item[[trial]]$meta$trialid
  sac$trialnum <- dat$item[[trial]]$meta$trialnum
  sac$itemid <- dat$item[[trial]]$meta$itemid
  sac$cond <- dat$item[[trial]]$meta$cond
  
  # sac$peak.vel <- NA
  # sac$dx <- NA
  # sac$dy <- NA
  # sac$dX <- NA
  # sac$dY <- NA
  # sac$dist.px <- NA
  # sac$dist.angle <- NA
  # sac$amp.px <- NA
  # sac$amp.angle <- NA
  
  for (s in 1:nrow(sac)) {
   # s = 1
    
    # on-/offset
    a <- sac$start[s]
    b <- sac$stop[s]

    if (is.null(dat$item[[trial]]$xy$x[dat$item[[trial]]$xy$time >= a & dat$item[[trial]]$xy$time <= b]) == TRUE) {
        dat$item[[trial]]$xy$x[a:b] <- NA
    }
    
    # if (is.na(dat$item[[trial]]$xy$x[dat$item[[trial]]$xy$time >= a & dat$item[[trial]]$xy$time <= b])[1] == FALSE) {
    # 
    #   if (is.na(dat$item[[trial]]$meta$calibration.method) == F) {
    #     
    #     # saccade peak velocity (vpeak)
    #     if (dat$item[[trial]]$meta$calibration.method != "H3") {
    #       sac$peak.vel[s] <- round(max(sqrt(dat$item[[trial]]$vxy$x[dat$item[[trial]]$vxy$time >= a &
    #                                                                   dat$item[[trial]]$vxy$time <= b]^2
    #                                         + dat$item[[trial]]$vxy$y[dat$item[[trial]]$vxy$time >= a &
    #                                                                     dat$item[[trial]]$vxy$time <= b]^2),
    #                                    na.rm = T))
    #     } else {
    #       sac$peak.vel[s] <- round(max(sqrt(dat$item[[trial]]$vxy$x[dat$item[[trial]]$vxy$time >= a &
    #                                                                   dat$item[[trial]]$vxy$time <= b]^2),
    #                                    na.rm = T))
    #     }
    # 
    #     # saccade distance (dx, dy)
    #     sac$dx[s] <- round(dat$item[[trial]]$xy[dat$item[[trial]]$xy$time <= b, 2] -
    #                          dat$item[[trial]]$xy[dat$item[[trial]]$xy$time >= a, 2])
    #     if (dat$item[[trial]]$meta$calibration.method != "H3") {
    #       sac$dy[s] <- round(dat$item[[trial]]$xy[dat$item[[trial]]$xy$time <= b, 3] -
    #                            dat$item[[trial]]$xy[dat$item[[trial]]$xy$time >= a, 3])
    #     }
    # 
    #     # saccade amplitude (dX, dY)
    #     minx <- min(dat$item[[trial]]$xy[dat$item[[trial]]$xy$time >= a
    #                                      & dat$item[[trial]]$xy$time <= b, 2])
    #     maxx <- max(dat$item[[trial]]$xy[dat$item[[trial]]$xy$time >= a
    #                                      & dat$item[[trial]]$xy$time <= b, 2])
    #     if (dat$item[[trial]]$meta$calibration.method != "H3") {
    #       miny <- min(dat$item[[trial]]$xy[dat$item[[trial]]$xy$time >= a
    #                                        & dat$item[[trial]]$xy$time <= b, 3])
    #       maxy <- max(dat$item[[trial]]$xy[dat$item[[trial]]$xy$time >= a
    #                                        & dat$item[[trial]]$xy$time <= b, 3])
    #     }
    #     ix1 <- which.min(dat$item[[trial]]$xy[dat$item[[trial]]$xy$time >= a
    #                                           & dat$item[[trial]]$xy$time <= b, 2])
    #     ix2 <- which.max(dat$item[[trial]]$xy[dat$item[[trial]]$xy$time >= a
    #                                           & dat$item[[trial]]$xy$time <= b, 2])
    #     if (dat$item[[trial]]$meta$calibration.method != "H3") {
    #       iy1 <- which.min(dat$item[[trial]]$xy[dat$item[[trial]]$xy$time >= a
    #                                             & dat$item[[trial]]$xy$time <= b, 3])
    #       iy2 <- which.max(dat$item[[trial]]$xy[dat$item[[trial]]$xy$time >= a
    #                                             & dat$item[[trial]]$xy$time <= b, 3])
    #     }
    #     sac$dX[s] <- round(sign(ix2 - ix1) * (maxx - minx))
    #     if (dat$item[[trial]]$meta$calibration.method != "H3") {
    #       sac$dY[s] <- round(sign(iy2 - iy1) * (maxy - miny))
    #     }
    # 
    #     # saccade distance/angle
    #     if (dat$item[[trial]]$meta$calibration.method != "H3") {
    #       sac$dist.px[s] <- round(sqrt(sac$dx[s]^2 + sac$dy[s]^2))
    #       sac$dist.angle[s] <- round(atan2(sac$dy[s], sac$dx[s]), 2)
    #     } else {
    #       sac$dist.px[s] <- NA
    #       sac$dist.angle[s] <- NA
    #     }
    # 
    #     # saccade amplitude/angle
    #     if (dat$item[[trial]]$meta$calibration.method != "H3" ) {
    #       sac$amp.px[s] <- round(sqrt(sac$dX[s]^2 + sac$dY[s]^2))
    #       sac$amp.angle[s] <- round(atan2(sac$dY[s], sac$dX[s]), 2)
    #     } else {
    #       sac$amp.px[s] <- NA
    #       sac$amp.angle[s] <- NA
    #     }
    #     
    #   }
    # 
    # }
    
    # saccade distance in letters
    sac$dist.let[s] <- sac$lete[s] - sac$lets[s]

    # duration
    sac$dur[s] <- b - a + 1
    
  }
  
  
  # rename fixid
  sac$sacid <- sac$num
  
  # names and return
  # names <- c("subid", "trialid", "trialnum", "itemid", "cond", "sacid", "msg",
  #              "xs", "xe", "ys", "ye", "xsn", "xen", "ysn", "yen", "start", "stop",
  #              "dist.px", "dist.angle", "dist.let", "peak.vel", "dur")
  names <- c("subid", "trialid", "trialnum", "itemid", "cond", "sacid", "msg",
             "xs", "xe", "ys", "ye", "xsn", "xen", "ysn", "yen", "start", "stop",
             "dist.let", "dur")
  sac <- sac[names]
  
  # treat very long saccades as blinks (controlled by exclude.sac)
  sac$msg[sac$dur > env$exp$setup$exclude$sac] <- "BLINK"

  dat$item[[trial]]$sac <- sac[is.na(sac$start) == F, ]
  
  return(dat)  
  
}