Layer a Raster Image

This function is very similar to the rasterImage function. It works with every loon plot which is based on the cartesian coordinate system.

l_layer_rasterImage(widget, image, xleft, ybottom, xright, ytop,
  angle = 0, interpolate = FALSE, parent = "root", index = "end",
  ...)

Arguments

widget	widget path as a string or as an object handle
image	a raster object, or an object that can be coerced to one by as.raster.
xleft	a vector (or scalar) of left x positions.
ybottom	a vector (or scalar) of bottom y positions.
xright	a vector (or scalar) of right x positions.
ytop	a vector (or scalar) of top y positions.
angle	angle of rotation (in degrees, anti-clockwise from positive x-axis, about the bottom-left corner).
interpolate	a logical vector (or scalar) indicating whether to apply linear interpolation to the image when drawing.
parent	parent widget path
index	position among its siblings. valid values are 0, 1, 2, ..., 'end'
...	argumnets forwarded to l_layer_line

Value

layer id of group or rectangles layer

Details

For more information run: l_help("learn_R_layer.html#countourlines-heatimage-rasterimage")

Examples

plot(1,1, xlim = c(0,1), ylim=c(0,1))
mat <- matrix(c(0,0,0,0, 1,1), ncol=2)
rasterImage(mat, 0,0,1,1, interpolate = FALSE)

p <- l_plot()
l_layer_rasterImage(p, mat, 0,0,1,1)
#> loon layer "rectangles" of type rectangles of plot .l78.plot
#> [1] "layer0"
l_scaleto_world(p)

image <- as.raster(matrix(0:1, ncol = 5, nrow = 3))
#> Warning: data length [2] is not a sub-multiple or multiple of the number of rows [3]
p <- l_plot(showScales=TRUE, background="thistle", useLoonInspector=FALSE)
l_layer_rasterImage(p, image, 100, 300, 150, 350, interpolate = FALSE)
#> loon layer "rectangles" of type rectangles of plot .l79.plot
#> [1] "layer0"
l_layer_rasterImage(p, image, 100, 400, 150, 450)
#> loon layer "rectangles" of type rectangles of plot .l79.plot
#> [1] "layer1"
l_layer_rasterImage(p, image, 200, 300, 200 + 10, 300 + 10,
   interpolate = FALSE)
#> loon layer "rectangles" of type rectangles of plot .l79.plot
#> [1] "layer2"
l_scaleto_world(p)

# from examples(rasterImage)

# set up the plot region:
op <- par(bg = "thistle")
plot(c(100, 250), c(300, 450), type = "n", xlab = "", ylab = "")
rasterImage(image, 100, 300, 150, 350, interpolate = FALSE)
rasterImage(image, 100, 400, 150, 450)
rasterImage(image, 200, 300, 200 + 10, 300 + 10,
           interpolate = FALSE)