Add a raster image to a plot

Adds a raster image (a 3D array) to an existing plot as an image. A silly, generic function, but nice for visualization. Sort of like graphics::points, but for images.

Usage

add_image(obj, x = NULL, y = NULL, width = NULL, interpolate = TRUE, angle = 0)

Arguments

obj

An array of the dimensions height x width x channels, such as read in by png::readPNG or readImage, or the original_img and recolored_img elements of a recolorize object.

x, y

The x and y coordinates on which the image should be centered.

width

Image width, in x-axis units.

interpolate

Passed to graphics::rasterImage. Use linear interpolation when scaling the image?

angle

Passed to graphics::rasterImage. The angle (in degrees) for rotating the image.

Value

Nothing; adds an image to the existing plot window.

Examples

images <- dir(system.file("extdata", package = "recolorize"),
              ".png", full.names = TRUE)
x <- runif(5)
y <- runif(5)
plot(x, y,
     xlim = range(x) + c(-0.2, 0.2),
     ylim = range(y) + c(-0.2, 0.2))
for (i in 1:length(images)) {
  img <- readImage(images[i])
  add_image(img, x[i], y[i], width = 0.1)
}