Detect and Handle Dateline Crossing in Line Segments

Source: R/functions.R

Normalizes longitude coordinates when a line segment crosses the ±180° dateline, preventing discontinuities in buffering and visualization.

fix_dateline_crossing(segment)

Arguments

segment

sf linestring object representing a transect or track

Value

sf linestring object with normalized coordinates (0-360° range if dateline is crossed)

Details

Dateline crossings are detected by checking for longitude jumps > 180°. When detected, negative longitudes are shifted to 0-360° range. The segment is then segmentized to 1000m intervals for smooth buffering.

See also

buffer_transect for usage in buffering workflow

Examples

if (FALSE) { # \dontrun{
# transect crossing the dateline
coords <- matrix(c(175, 30, -175, 35), ncol = 2, byrow = TRUE)
segment <- st_sf(st_sfc(st_linestring(coords), crs = 4326))
normalized <- fix_dateline_crossing(segment)
} # }