R代表Windows的TTF / OTF字体选择：屏幕与pdf()

我知道在 Linux或Mac上的R中,字体一直被定义为参数family =“Charis SIL”到par(),text()或其中一个图形设备函数,如tiff(),svg()等(用你想要的任何字体名称替换“Charis SIL”.我也知道在Windows上,它只适用于cairo_pdf()和svg()设备;像jpeg(),tiff(),png()和bmp()之类的光栅图形设备要求首先在“Windows字体数据库”中映射字体：

# this doesn't work on windows
jpeg(filename='test1.jpg',family='Charis SIL')
plot(0,type='n',ann=FALSE,frame.plot=FALSE)
text(0,labels='iye???a????ɑ????o?u???????????')
dev.off()
# (gives warnings: Font family not found in Windows font database)  

# this does work on windows (assuming you have the Charis SIL font installed)
windowsFonts(myCustomWindowsFontName=windowsFont('Charis SIL'))
jpeg(filename='test2.jpg',family='myCustomWindowsFontName')
plot(0,labels='iye???a????ɑ????o?u???????????')
dev.off()

pdf()设备仍然不同：它似乎需要在postscriptFonts()和/或pdfFonts()数据库中定义的字体,这意味着只有Type1字体：

# this doesn't work on windows
pdf('test.pdf',family='Charis SIL')
# gives error: Unknown family "Charis SIL"

# this doesn't work either
windowsFonts(myCustomWindowsFontName=windowsFont('Charis SIL'))
pdf('test.pdf',family='myCustomWindowsFontName')
# gives error: Unknown family "myCustomWindowsFontName"

# this also won't work
pdf.options(family='Charis SIL')
pdf('test.pdf')
# gives error: Invalid font type
# also gives warning: font family "Charis SIL" not found in Postscript font database

通常这没关系,因为cairo_pdf()是pdf()设备的一个很好的替代品,并且处理TTF和OTF字体就好了.问题是,如果用户绘制到屏幕设备,然后使用菜单命令保存为PDF,它似乎调用pdf()而不是cairo_pdf(),然后抛出错误：

# this part works
windowsFonts(myCustomWindowsFontName=windowsFont('Charis SIL'))
par(family='myCustomWindowsFontName')
plot(0,labels='iye???a????ɑ????o?u???????????')

# but menu command "File > Save As > PDF" gives errors:
# Error: Invalid font type
# Warning: font family "Charis SIL" not found in Postscript font database

这是一个问题,因为我正在开发的R软件包在Windows上无法“R CMD检查”,显然是因为示例代码生成的屏幕输出会自动保存为PDF,从而产生上述错误.一种解决方案是放弃Windows中屏幕设备的自定义字体(即,如果所选输出是“屏幕”,则忽略“家庭”参数).另一个选择是使用Cairo()包进行屏幕绘图,但如果可以,我更愿意坚持使用基本图形.有没有什么办法可以在屏幕上绘制自定义字体而不会在使用“另存为PDF”菜单命令时抛出错误？

oldSans <- windowsFonts()$sans
windowsFonts(sans=windowsFont('Charis SIL'))
par(family='sans') # this line isn't necessary anymore
plot(0,labels='iye???a????ɑ????o?u???????????')
windowsFonts(sans=oldSans)