Using geom_shadowtext() in custom function fails; missing alpha imports?

[Kevin Stierhoff]

Hi,
I created a function in my own package that creates a ggplot2 object with a geom_shadowtext() layer for labels. When I run the code, it fails with the following error:

Error in alpha(data$colour, data$alpha) : could not find function "alpha"

I've included shadowtext in my imports, as well as ggplot2. I also don't use alpha anywhere else in the function, but I can see from your code posted here that GeomShadowText uses ggproto, which in turn has an argument for alpha, which I presume is causing the issue. Is this an issue with imports in shadowtext? Or can you think of a workaround? I'm not immediately able to think of a minimal reproducible example, but if I do, I'll post here. Sorry about that.

Thanks,
Kevin

[Kevin Stierhoff]

Thank you!

[Kevin Stierhoff]

Hi,
So that error is fixed, but now I get a different error:
Error in numnotnull("fontsize") : object '.pt' not found

Below is a minimal reprex that I hope will illustrate the problem:

# Test data frame
xy_df <- data.frame(x = 1, y = 1, name = "test")

# Function using geom_text
text_ex <- function(xy_df) {
  ggplot2::ggplot() +
    ggplot2::geom_text(data  = xy_df, ggplot2::aes(x, y, label = name))
}

# Function using geom_shadowtext
shadow_ex <- function(xy_df) {
  ggplot2::ggplot() +
    shadowtext::geom_shadowtext(data  = xy_df, ggplot2::aes(x, y, label = name))
}

# This works
text_ex(xy_df)

# This does not
shadow_ex(xy_df)

I assume it relates to this portion of your shadowtextGrob function:

Thanks,
Kevin

[Guangchuang Yu]

fixed.

[Kevin Stierhoff]

Thank-you, again! Working great now.