Mac中ggplot无法为Google字体Raleway设置加粗/斜体的技术求助

在Mac的Font Book中下载并保存了Google字体Raleway，但无法在ggplot中为其设置加粗、斜体样式。示例代码如下：

ggplot() +
  labs(title = "Title in Bold",
       subtitle = "Subtitle in Italics") +
  xlab("Y Label") +
  ylab("X Label") +
  theme(text = element_text(family = "Raleway"),
        plot.title = element_text(face = 'bold', size = 18),
        plot.subtitle = element_text(face = 'italic')
        )

运行后字体显示为Raleway常规样式，但标题的加粗、副标题的斜体均未生效。

尝试使用extrafont包的font_import()时，返回提示：

"/Users/username/Library/Fonts/Raleway-Italic-VariableFont_wght.ttf : Raleway-ThinItalic already registered in fonts database. Skipping.
/Users/username/Library/Fonts/Raleway-VariableFont_wght.ttf : Raleway-Thin already registered in fonts database. Skipping."

切换至AGG图形后端或使用showtext::showtext_auto()时，均出现警告：In grid.Call.graphics(C_text, as.graphicsAnnot(x$label), ... : Unable to load font: Raleway。

该字体的加粗、斜体样式可在Microsoft Word等其他应用中正常使用，需解决在R中正确加载并注册这些字体样式的问题。

会话信息：

R version 4.3.3 (2024-02-29)
Platform: aarch64-apple-darwin20 (64-bit)
Running under: macOS Sonoma 14.4.1
Matrix products: default
BLAS:   /System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/libBLAS.dylib
LAPACK: /Library/Frameworks/R.framework/Versions/4.3-arm64/Resources/lib/libRlapack.dylib;  LAPACK version 3.11.0
locale:
1 en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8
time zone: America/Los_Angeles
tzcode source: internal
attached base packages:
1 stats     graphics  grDevices utils     datasets  methods   base
other attached packages:
1 extrafont_0.19  lubridate_1.9.3 forcats_1.0.0   stringr_1.5.1   dplyr_1.1.4     purrr_1.0.2     readr_2.1.5
[8] tidyr_1.3.1     tibble_3.2.1    ggplot2_3.5.0   tidyverse_2.0.0 RPostgres_1.4.6
loaded via a namespace (and not attached):
1 cfbfastR_1.9.0     DBI_1.2.2          remotes_2.5.0      writexl_1.5.0      rlang_1.1.3        magrittr_2.0.3
[7] snakecase_0.11.1   furrr_0.3.1        compiler_4.3.3     mgcv_1.9-1         png_0.1-8          systemfonts_1.0.6
[13] vctrs_0.6.5        reshape2_1.4.4     sysfonts_0.8.9     rvest_1.0.4        profvis_0.3.8      crayon_1.5.2
[19] pkgconfig_2.0.3    fastmap_1.1.1      backports_1.4.1    ellipsis_0.3.2     labeling_0.4.3     utf8_1.2.4
[25] promises_1.2.1     rmarkdown_2.26     sessioninfo_1.2.2  tzdb_0.4.0         ps_1.7.6           bit_4.0.5
[31] xfun_0.43          showtext_0.9-7     cachem_1.0.8       jsonlite_1.8.8     blob_1.2.4         later_1.3.2
[37] emoji_15.0         jpeg_0.1-10        broom_1.0.5        parallel_4.3.3     R6_2.5.1           stringi_1.8.3
[43] espnscrapeR_0.8.0  extrafontdb_1.0    parallelly_1.37.1  pkgload_1.3.4      assertthat_0.2.1   Rcpp_1.0.12
[49] knitr_1.45         usethis_2.2.3      pacman_0.5.1       nnet_7.3-19        Matrix_1.6-5       httpuv_1.6.15
[55] splines_4.3.3      timechange_0.3.0   tidyselect_1.2.1   rstudioapi_0.16.0  yaml_2.3.8         codetools_0.2-19
[61] miniUI_0.1.1.1     websocket_1.4.1    curl_5.2.1         processx_3.8.4     listenv_0.9.1      pkgbuild_1.4.4
[67] lattice_0.22-6     plyr_1.8.9         withr_3.0.0        shiny_1.8.1        evaluate_0.23      future_1.33.1
[73] RcppParallel_5.1.7 urlchecker_1.0.1   xml2_1.3.6         pillar_1.9.0       generics_0.1.3     chromote_0.2.0
[79] hms_1.1.3          munsell_0.5.0      scales_1.3.0       globals_0.16.3     xtable_1.8-4       emo_0.0.0.9000
[85] glue_1.7.0         janitor_2.2.0      mlbplotR_1.1.0     tools_4.3.3        data.table_1.15.2  fs_1.6.3
[91] grid_4.3.3         Rttf2pt1_1.3.12    devtools_2.4.5     colorspace_2.1-0   nlme_3.1-164       patchwork_1.2.0
[97] showtextdb_3.0     proto_1.0.0        baseballr_1.6.0    cli_3.6.2          fansi_1.0.6        gt_0.10.1
[103] V8_4.4.2           emojifont_0.5.5    gtable_0.3.4       digest_0.6.35      farver_2.1.1       htmlwidgets_1.6.4
[109] memoise_2.0.1      htmltools_0.5.8    lifecycle_1.0.4    httr_1.4.7         mime_0.12          bit64_4.0.5

核心原因 #

R的字体系统对**可变字体（Variable Font）**的支持有限，你安装的Raleway是可变字体文件（Raleway-VariableFont_wght.ttf），仅靠指定face = 'bold'无法触发字重变化，需要明确注册或调用对应字重的字体变体。

方法1：直接指定字体变体名称 #

• 先查看系统中已安装的Raleway所有变体：

  systemfonts::system_fonts() |> dplyr::filter(grepl("Raleway", family))
  

• 根据输出的family或fullname，直接在element_text中指定对应变体，比如：

  ggplot() +
    labs(title = "Title in Bold",
         subtitle = "Subtitle in Italics") +
    xlab("Y Label") +
    ylab("X Label") +
    theme(
      text = element_text(family = "Raleway"),
      plot.title = element_text(family = "Raleway Bold", size = 18),
      plot.subtitle = element_text(family = "Raleway Italic")
    )
  

方法2：重新安装单文件变体字体 #

如果可变字体兼容性问题无法解决，直接从Google Fonts下载Raleway的单个字重/样式文件（比如Raleway-Bold.ttf、Raleway-Italic.ttf等），安装到Font Book后：

• 清理extrafont缓存：

  extrafont::font_remove("Raleway")
  unlink("~/.fonts", recursive = TRUE)
  

• 重新导入字体：

  extrafont::font_import(pattern = "Raleway", prompt = FALSE)
  extrafont::loadfonts(device = "pdf") # 根据需要加载对应设备（如"win"或"postscript"）
  

• 重启R后再运行ggplot代码，此时face = 'bold'/'italic'即可生效。

方法3：使用showtext正确加载可变字体 #

针对可变字体，showtext需要明确指定字重参数：

• 注册字体：

  showtext::font_add("Raleway", 
                     regular = "/Users/username/Library/Fonts/Raleway-VariableFont_wght.ttf",
                     bold = "/Users/username/Library/Fonts/Raleway-VariableFont_wght.ttf",
                     italic = "/Users/username/Library/Fonts/Raleway-Italic-VariableFont_wght.ttf")
  

• 启用showtext：

  showtext::showtext_auto()
  

• 运行ggplot代码时，可通过weight参数指定字重（比如weight = 700对应加粗）：

  ggplot() +
    labs(title = "Title in Bold",
         subtitle = "Subtitle in Italics") +
    xlab("Y Label") +
    ylab("X Label") +
    theme(
      text = element_text(family = "Raleway"),
      plot.title = element_text(weight = 700, size = 18),
      plot.subtitle = element_text(face = "italic")
    )
  

内容的提问来源于stack exchange，提问作者Violin125