Pattern

[yutannihilation]

https://www.stat.auckland.ac.nz/~paul/Reports/GraphicsEngine/definitions/definitions.html

[yutannihilation]

liner gradient

This works

grid.rect(gp=gpar(fill=linearGradient()))

extend = "none" doesn't work because there's no such option on vello.

# expected the bottom 1 inch is not filled
grid.rect(gp=gpar(fill=linearGradient(c("red", "yellow", "red"),
                                      c(0, .5, 1),
                                      x1=.5, y1=unit(1, "in"),
                                      x2=.5, y2=1,
                                      extend="none")))

radial gradient

This works.

grid.rect(gp=gpar(fill=radialGradient(c("white", "black"),
                                      cx1=.8, cy1=.8)))

other

This doesn't work for some reason.

library(ggplot2)

ggplot(mtcars) +
    geom_point(aes(x=disp, y=mpg)) +
    theme_bw()
grid.force()
grid.edit("panel.background", grep=TRUE,
          gp=gpar(fill=linearGradient(c("grey", "white"), x1=.5, x2=.5)))

[yutannihilation]

Regarding the last problem

• The points and lines disappear on grid.edit() of gradient. However, it displays fine with a plain color.
• The points and polylines drawn after ggplot() are not affected.
• If I disable the clipping (so push_layer() and pop_layer()), the result is the same.

vellogd-20241026.mp4

[yutannihilation]

Hmm, let's merge this for now.