SVG to PNG
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Here is a way to get a high-quality PNG image with R: save it as SVG first, then convert the SVG file to a PNG file, with the rsvg package.
Let’s see. I construct a hyperbolic Delaunay triangulation with the gyro package:
library(gyro)
phi <- (1 + sqrt(5)) / 2
theta <- head(seq(0, pi/2, length.out = 11), -1L)
a <- phi^((2*theta/pi)^0.8 - 1)
u <- a * cos(theta)
v <- a * sin(theta)
x <- c(0, u, -v, -u, v)
y <- c(0, v, u, -v, -u)
pts <- cbind(x, y) / 1.07
hdel <- hdelaunay(pts, model = "U")
fcolor <- function(t){
RGB <- colorRamp(hcl.colors(20L, "Berlin"))(t)
rgb(RGB[, 1L], RGB[, 2L], RGB[, 3L], maxColorValue = 255)
}
Now let’s save the plot as a PNG, directly:
png("hdelaunayU.png", width = 512, height = 512)
plotHdelaunay(
hdel, vertices = FALSE, color = fcolor
)
dev.off()
And now let’s save it as SVG then convert it to PNG:
svg("hdelaunayU.svg")
plotHdelaunay(
hdel, vertices = FALSE, color = fcolor
)
dev.off()
rsvg::rsvg_png(
"hdelaunayU.svg", "hdelaunayU_from_svg.png",
width = 512, height = 512
)
Observe the difference:
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