agg_png renders plotmath %*% as centered dot (·) instead of multiplication sign (×)

[davidzgli]

Description

ragg::agg_png renders the plotmath %*% operator as a centered dot (· U+00B7) instead of the multiplication sign (× U+00D7). grDevices::png renders it correctly as ×.

Expected: expression(italic(P) == 2.36 %*% 10^-05) renders with × (multiplication sign)
Actual: The same expression renders with · (middle dot / centered dot) when using agg_png

Minimal reprex

library(ragg)

expr <- expression(italic(P) == 2.36 %*% 10^-05)

# ragg: %*% renders as centered dot (·)
agg_png("reprex_ragg.png", width = 400, height = 150, res = 150)
par(mar = c(1, 1, 2, 1))
plot.new()
title(main = "ragg::agg_png")
text(0.5, 0.5, expr, cex = 1.5)
dev.off()

# grDevices: %*% renders correctly as multiplication sign (×)
grDevices::png("reprex_grdevices.png", width = 400, height = 150, res = 150)
par(mar = c(1, 1, 2, 1))
plot.new()
title(main = "grDevices::png")
text(0.5, 0.5, expr, cex = 1.5)
dev.off()

Compare reprex_ragg.png (shows ·) with reprex_grdevices.png (shows ×).

Session info

• R 4.5.2 (2025-10-31)
• Platform: x86_64-pc-linux-gnu (Linux)
• ragg 1.5.0

Related issues

This may be related to other symbol/font rendering issues:

• ragg does not render minus sign in axis title superscript #89
• Request: allow user to specify Symbol font #90
• sf + ggplot + ragg doesn't print degree symbol #51

[thomasp85]

This seems platform dependent and thus point to your linux installation using a suboptimal font for symbol. You should look into your font config setup and see if you can direct symbol to a better font