Methods for creating image files of a specific format.
toBMP(name, ...)
   toPDF(name, ...)
   toPNG(name, ...)
   toSVG(name, ...)
   toTIFF(name, ...)
   toEMF(name, ..., ext="emf")
   toWMF(name, ..., ext="wmf")   toFavicon(..., name="favicon", ext="png",
             field=getDevOption("favicon", "field", default="htmlscript"))
   
   toDefault(name, ...)
   toQuartz(name, ...)
   toX11(name, ...)
   toWindows(name, ...)
   
   toCairoWin(name, ...)
   toCairoX11(name, ...)
   
   
   toRStudioGD(name, ..., .allowUnknownArgs = TRUE)
Returns by default the DevEvalProduct.
   For toFavicon() the default return value is a character string.
A character string specifying the name of the image file.
Additional arguments passed to devEval(), e.g.
      tags and aspectRatio.
Passed to devEval().
Both toEMF() and toWMF() use the exact same graphics
   device (win.metafile()) and settings.  They only differ by
   filename extension.  The win.metafile() device function exists
   on Windows only; see the grDevices package for more details.
Henrik Bengtsson
These functions are wrappers for devEval().
   See devOptions() to change the default dimensions for
   a specific device type.