1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
|
% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/draw.R
\name{draw_image}
\alias{draw_image}
\title{Draw an image}
\usage{
draw_image(
image,
x = 0,
y = 0,
width = 1,
height = 1,
scale = 1,
clip = "inherit",
interpolate = TRUE,
hjust = 0,
vjust = 0,
halign = 0.5,
valign = 0.5
)
}
\arguments{
\item{image}{The image to place. Can be a file path, a URL, or a raw vector with image data,
as in \code{magick::image_read()}. Can also be an image previously created by \code{magick::image_read()} and
related functions.}
\item{x}{The x location of the image. (Left side if \code{hjust = 0}.)}
\item{y}{The y location of the image. (Bottom side if \code{vjust = 0}.)}
\item{width}{Width of the image.}
\item{height}{Height of the image.}
\item{scale}{Scales the image relative to the rectangle defined by \code{x}, \code{y}, \code{width}, \code{height}. A setting
of \code{scale = 1} indicates no scaling.}
\item{clip}{Set to "on" to clip the image relative to the box into which it is draw (useful for \code{scale > 1}).
Note that clipping doesn't always work as expected, due to limitations of the grid graphics system.}
\item{interpolate}{A logical value indicating whether to linearly interpolate the image
(the alternative is to use nearest-neighbour interpolation, which gives a more blocky result).}
\item{hjust, vjust}{Horizontal and vertical justification relative to x.}
\item{halign, valign}{Horizontal and vertical justification of the image inside
the box.}
}
\description{
Places an image somewhere onto the drawing canvas. By default, coordinates run from
0 to 1, and the point (0, 0) is in the lower left corner of the canvas. Requires the \code{magick}
package to work, and fails gracefully if that package is not installed.
}
\examples{
library(ggplot2)
# Use image as plot background
p <- ggplot(iris, aes(x = Sepal.Length, fill = Species)) +
geom_density(alpha = 0.7) +
scale_y_continuous(expand = expansion(mult = c(0, 0.05))) +
theme_half_open(12)
logo_file <- system.file("extdata", "logo.png", package = "cowplot")
ggdraw() +
draw_image(
logo_file, scale = .7
) +
draw_plot(p)
# Place in lower right corner
ggdraw() +
draw_image(
logo_file, scale = .3, x = 1,
hjust = 1, halign = 1, valign = 0
) +
draw_plot(p)
\dontrun{
# Make grid with plot and image
cow_file <- system.file("extdata", "cow.jpg", package = "cowplot")
p2 <- ggdraw() + draw_image(cow_file, scale = 0.9)
plot_grid(
p + theme(legend.position = c(1, 1), legend.justification = c(1, 1)),
p2,
labels = "AUTO"
)
# Manipulate images and draw in plot coordinates
if (requireNamespace("magick", quietly = TRUE)){
img <- magick::image_transparent(
magick::image_read(logo_file),
color = "white"
)
img2 <- magick::image_negate(img)
ggplot(data.frame(x = 1:3, y = 1:3), aes(x, y)) +
geom_point(size = 3) +
geom_abline(slope = 1, intercept = 0, linetype = 2, color = "blue") +
draw_image(img , x = 1, y = 1, scale = .9) +
draw_image(img2, x = 2, y = 2, scale = .9)
}
}
}
|
