makeBallIcon: Create an icon image file

In duncantl/RKML: Simple tools for creating KML displays from R

Description

These functions are used to create icon images for placing on Google Earth (i.e. an icon for a place mark on the earth).

Usage

makeBallIcon(col = "red", file = "/tmp/ball.png", width = 40, height = width, radius = 0.43)
makeRectIcon(col = "red", file = "/tmp/rect.png", width = 40, height = width, radius = 1)
makePchIcon(pch = "red", col = "red", file = sprintf("pch_%s.png", as.character(pch)),
              cex = 4, width = 40, height = width, radius = 1)

Arguments

col	a color used to control the color of the shape or character being drawn, passed to a call to symbols, points or text.
file	the name of the PNG file to create
width,height	the width and height of the image to create, in pixels
radius	the size of the symbol to draw
pch	the plotting character to draw in the image
cex	character expansion factor passed on to text.

Value

a character string giving the name of the generated PNG file.

Author(s)

Duncan Temple Lang

See Also

kml, kmlPoints and the styles parameter.

Examples

  makeBallIcon("red")
  makePchIcon(17, "#0000FF")

  mapply(makeRectIcon, heat.colors(7), sprintf("heat_%d.png", 1:7))

  data(quakes)

  mag = factor(as.integer(quakes$magnitude))
  icons = mapply(makeBallIcon, heat.colors(length(levels(mag))), sprintf("heat_%d.png", 1:length(levels(mag))))
  styles = lapply(icons, function(x) list(IconStyle = list(scale = ".5", Icon = c(href = x))))
  names(styles) = gsub(".png", "", icons)

  doc = kml(~ longitude + latitude, quakes, styles = styles,  col = names(styles)[mag])

duncantl/RKML documentation built on May 15, 2019, 5:31 p.m.