kmlLine               package:maptools               R Documentation

_C_r_e_a_t_e _a_n_d _w_r_i_t_e _a _K_M_L _f_i_l_e _o_n _t_h_e _b_a_s_i_s _o_f _a _g_i_v_e_n _L_i_n_e_s _o_b_j_e_c_t

_D_e_s_c_r_i_p_t_i_o_n:

     The function is used to create and write a KML file on the basis
     of a given Lines object (a list of Line objects) for the usage in
     Google Earth resp. Google Maps.

_U_s_a_g_e:

     kmlLine(obj=NULL, kmlfile=NULL, 
         name="R Line", description="", col=NULL, visibility=1, lwd=1,
         kmlname="", kmldescription="")
     x <- kmlLine(obj=NULL,
         name="R Line", description="", col=NULL, visibility=1, lwd=1,
         kmlname="", kmldescription="")
     y <- kmlLine(kmlname="", kmldescription="")

_A_r_g_u_m_e_n_t_s:

     obj: a 'Lines' or 'SpatialLinesDataFrame' object

 kmlfile: if not 'NULL' the name as character string of the kml file to
          be written

    name: the name of the KML line

description: the description of the KML line (HTML tags allowed)

     col: the stroke color (see also Color Specification) of the KML
          line

visibility: if set to '1' or 'TRUE' specifies that the KML line should
          be visible after loading

     lwd: the stroke width for the KML line

 kmlname: the name of the KML layer

kmldescription: the description of the KML layer (HTML tags allowed)

_D_e_t_a_i_l_s:

     The function is used to convert a given 'Lines' object (a list of
     Line objects) or the first 'Lines' object listed in a passed
     'SpatialLinesDataFrame' object into KML line(s). If 'kmlfile' is
     not 'NULL' the result will be written into that file. If 'kmlfile'
     is 'NULL' the generated KML lines will be returned (see also
     value). 

     For a passed 'Lines' object the function generates a <Style> tag
     whereby its id attribute is set to the passed object's ID.

     The resulting KML line will be embedded in
     '<Placemark><MultiGeometry><LineString>'.

_V_a_l_u_e:

     x is a list with the elements 'style' and 'content' containing the
     generated lines of the KML file as character vectors if 'kmlfile'
     is 'NULL'.

     y is a list with the elements 'header' and 'footer' representing
     the KML file' header resp. footer if 'obj' is 'NULL'.

_C_o_l_o_r _S_p_e_c_i_f_i_c_a_t_i_o_n:

     The following color specifications are allowed: ''red'', '2', or
     as hex code ''#RRGGBB'' resp. ''#RRGGBBAA'' for passing the alpha
     value.

_A_u_t_h_o_r(_s):

     Hans-J. Bibiko

_S_e_e _A_l_s_o:

     'kmlOverlay', 'kmlPolygon', 'Lines'

_E_x_a_m_p_l_e_s:

     xx <- readShapeSpatial(system.file("shapes/fylk-val-ll.shp",
           package="maptools")[1], proj4string=CRS("+proj=longlat"))
     out <- sapply(slot(xx, "lines"), function(x) { kmlLine(x,
         name=slot(x, "ID"), col="blue", lwd=1.5, 
         description=paste("river:", slot(x, "ID"))) })
     tf <- tempfile()
     kmlFile <- file(tf, "w")
     tf
     cat(kmlLine(kmlname="R Test", kmldescription="<i>Hello</i>")$header, 
         file=kmlFile, sep="\n")
     cat(unlist(out["style",]), file=kmlFile, sep="\n")
     cat(unlist(out["content",]), file=kmlFile, sep="\n")
     cat(kmlLine()$footer, file=kmlFile, sep="\n")
     close(kmlFile)

