R/proj4.R

In r-gris/gris: A Flexible Geometry and Topology Model for Spatial Data in R

# 
# #' Map projection for gris
# #'
# #' @param x gris object
# #' @param target proj4 string
# #' @param ... passed to methods
# #'
# #' @return gris object
# #' @export
# #' @importFrom proj4 ptransform
# #' @examples 
# #' library(maptools)
# #' data(wrld_simpl)
# #' g <- gris(wrld_simpl[10, ])
# #' ptransform(g, "+proj=laea +ellps=WGS84")
# ptransform <- function(x, ...) {
#   UseMethod("ptransform")
# }
# 
# #' @rdname ptransform
# #' @export
# ptransform.gris <- function(x, target, ...) {
#   m <- x$v %>% select(x, y) %>% mutate(x = x * pi/180, y = y * pi/180)
#   m <- proj4::ptransform(m, src.proj = x$georef$proj4, dst.proj = target, ...)
#   x$v$x <- m[[1]]
#   x$v$y <- m[[2]]
#   x
# }
# ptransform.default <- function(x, ...) {
#   proj4::ptransform(data = x, ...)
# }
# 
# 
# #' @export
# #' @rdname gris-summary
# xmin <- function(x) UseMethod("xmin")
# 
# #' @export
# #' @rdname gris-summary
# xmax <- function(x) UseMethod("xmax")
# 
# #' @export
# #' @rdname gris-summary
# ymin <- function(x) UseMethod("ymin")
# 
# #' @export
# #' @rdname gris-summary
# ymax <- function(x) UseMethod("ymax")
# 
# 
# #' @export
# #' @rdname gris-summary
# xmin.default <- function(x) raster::xmin(x)
# 
# #' @export
# #' @rdname gris-summary
# xmax.default <- function(x) raster::xmax(x)
# 
# #' @export
# #' @rdname gris-summary
# ymin.default <- function(x) raster::ymin(x)
# 
# #' @export
# #' @rdname gris-summary
# ymax.default <- function(x) raster::ymax(x)
# 
# #' min/max for gris
# #'
# #' @param x gris object
# #'
# #' @return numeric
# #' @export
# #' @rdname gris-summary
# xmin.gris <- function(x) {
#   min(x$v$x)
# }
# 
# #' @export
# #' @rdname gris-summary
# xmax.gris <- function(x) max(x$v$x)
# 
# #' @export
# #' @rdname gris-summary
# ymin.gris <- function(x) min(x$v$y)
# 
# #' @rdname gris-summary
# ymax.gris <- function(x) max(x$v$y)
# 
# 
# #' @export
# #' @rdname gris-summary
# xrange <- function(x, ...) UseMethod("xrange")
# 
# #' @export
# #' @rdname gris-summary
# yrange <- function(x, ...) UseMethod("yrange")
# 
# #' @export
# #' @rdname gris-summary
# xrange.default <- function(x) c(raster::xmin(x), raster::xmax(x))
# 
# #' @export
# #' @rdname gris-summary
# yrange.default <- function(x) c(raster::ymin(x), raster::ymax(x))
# 
# #' @param family projection family
# #' @export
# #' @rdname gris-summary
# local_triangulate <- function(x, family = "laea") {
#   xmid <- mean(xrange(x))
#   ymid <- mean(yrange(x))
#   proj4 <- sprintf("+%s +lon_0=%f +lat_0=%f +ellps=WGS84", family, xmid, ymid)
#   proj4
# }