[BlindRUG] update on getting braille on plots

[Godfrey, Jonathan]

Hello all,

Recently there was an exchange about getting braille onto plots started by JooYoung. I've now got a solution that I think can be implemented by a blind user with access to their own embosser for generating a tactile graph with all text appearing in braille. The first two steps are from JooYoung's message. Much of the final solution was tested by Paul Murrell at the University of Auckland and me this week.


  1. I downloaded this font<http://www.fontspace.com/philing/braille-normal> and installed it.
  2. You need the braille font imported into R which uses an add-on package that you probably do not have. Get it using:

chooseCRANmirror(ind=1)
install.packages("extrafont")

3. Use the add-on package in each session by issuing:
library(extrafont)

4. After first installing and using the package, you need to issue the next two commands once per installation, not in every session.
font_import(".", pattern="BRAILLE1.ttf", prompt=FALSE)
loadfonts()

5. Import the data for your graph. I've used:
data(airquality)
attach(airquality)

6. Now draw that histogram example I always use:
pdf("hist-test-cex-ps.pdf", pointsize=29)
hist(Ozone, family="Braille Normal",
      cex=1, cex.axis=1, cex.main=1, cex.lab=1, cex.sub=1)
dev.off()
embed_fonts("hist-test-cex-ps.pdf", outfile="hist-test-cex-ps-embed.pdf")

N.B. the font size gets set in two ways. Once in the pdf creation and then by way of forcing all resizing of text (character expansion) to be left at a ratio of 1 instead of a variety of fractions. Failure to do both leads to small, possibly unreadable, braille.

7. Go to your working directory and open that pdf file ready for embossing. Your screen reader will speak words to you but the vision dependent will tell you there are braille dots on screen.

8. Emboss on paper that is wide enough for this file. I used 11x11.5 inch paper and it appears to have worked with the default image size used for the pdf() command. I am confident that we can find ways to make sure the final version of this workflow that goes into the BrailleR package will allow for different paper sizes.

9. Please report your findings. I do need to hear from those of you who have access to other embossers that can handle graphics. I will pass them on to Paul Murrell at the University of Auckland whose assistance has proven invaluable this week.

Thanks everyone,
Jonathan

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