shadowText_options function

Get and set options for shadowText

shadowText_options(
  r = getOption("jam.shadow.r", 0.15),
  n = getOption("jam.shadow.n", 8),
  outline = getOption("jam.outline", TRUE),
  alphaOutline = getOption("jam.alphaOutline", 0.4),
  shadow = getOption("jam.shadow", FALSE),
  shadowColor = getOption("jam.shadowColor", "black"),
  alphaShadow = getOption("jam.alphaShadow", 0.2),
  r_ex = 1,
  alpha_ex = 1,
  preset = c("none", "default", "bold", "bold white", "bold black", "both", "shadow",
    "bold shadow", "bold white shadow", "bold black shadow", "bold both"),
  verbose = FALSE,
  ...
)

Arguments

• r: numeric radius used for outline or shadow

• n: numeric number of shadow steps to render around each text label

• outline: logical indicating whether to render shadowText as an outline (default), or when outline=FALSE it renders a drop shadow offset using offset which by default is slightly down and to the right of the text labels.

• alphaOutline: numeric value for alpha transparency used for label outlines when outline=TRUE, with values expected between 0 (fully transparent) and 1 (not transparent).

• shadow: logical indicating whether to render shadowText as a shadow, or not (default).

• shadowColor: character R color which defines the color used for the outline or shadow for each text label.

• alphaShadow: numeric value for alpha transparency used for label shadows when shadow=TRUE, with values expected between 0 (fully transparent) and 1 (not transparent).

• r_ex: numeric expansion factor used to adjust the radius r. The value for r is defined based upon the arguments provided, then is multiplied by the r_ex expansion factor. The result is stored in option "jam.shadow.r".

• alpha_ex: numeric expansion factor used to adjust the alpha transparency of both alphaOutline and alphaShadow. Values will be maintained no lower than 0 and no higher than 1. The values for alphaOutline and alphaShadow are defined based upon the arguments provided, then are multiplied by the alpha_ex expansion factor. The result is clipped to range 0,1 using jamba::noiseFloor(). The resulting values are stored in options "jam.alphaOutline" and "jam.alphaShadow", respectively.

• preset: character string which defines a preset with associated settings. Any value other than "none" will cause all other options to use the preset settings.

  • "none": no preset settings are applied
  • "default": reverts all options to the original default values, which produces an outline, and not a drop shadow. The color will use shadowColor which allows using all other settings from this preset, except with custom color.
  • "bold": makes output produce visibly more distinct outline, with no drop shadow. The color will use shadowColor which allows using all other settings from this preset, except with custom color.
  • "bold white": same as "bold" except default text color is white
  • "bold black": same as "bold" except default text color is black
  • "both": applies "default" and enables drop shadow
  • "shadow": uses suggested default values to produce a drop shadow, and not an outline. The color will use shadowColor which allows using all other settings from this preset, except with custom color.
  • "bold shadow": same as "shadow" except the shadow is more distinct. The color will use shadowColor which allows using all other settings from this preset, except with custom color.
  • "bold white shadow": same as "bold shadow" with white shadow
  • "bold black shadow": same as "bold shadow" with black shadow
  • "bold both": same as "bold" except also enables bold shadow

• verbose: logical indicating whether to print verbose output

• ...: additional arguments are ignored.

Returns

list with the following options for shadowText():

• jam.shadow.r
• jam.shadow.n
• jam.outline
• jam.alphaOutline
• jam.shadow
• jam.shadowColor
• jam.alphaShadow

Details

This function is intended to be a convenient method to get and set options to be used with jamba::shadowText(). This function stores the resulting values in options() for use by shadowText().

Examples

nullPlot(doBoxes=FALSE, xlim=c(-1, 4), ylim=c(-1, 4), asp=1);
usrBox(fill="grey")
cex <- 1.2
graphics::axis(1);graphics::axis(2, las=2)
shadowText_options(preset="default")
shadowText(x=0, y=3, "default", cex=cex)
shadowText_options(preset="bold")
shadowText(x=0, y=2, "bold", cex=cex)
shadowText_options(preset="bold white")
shadowText(x=0, y=1, col="black", "bold white", cex=cex)
shadowText_options(preset="bold black")
shadowText(x=0, y=0, col="white", "bold black", cex=cex)
shadowText_options(preset="shadow")
shadowText(x=3, y=3, "shadow", cex=cex)
shadowText_options(preset="bold shadow")
shadowText(x=3, y=2, "bold shadow", cex=cex)
shadowText_options(preset="bold white shadow")
shadowText(x=3, y=1, col="black", "bold white shadow", cex=cex)
shadowText_options(preset="bold black shadow")
shadowText(x=3, y=0, col="white", "bold black shadow", cex=cex)
shadowText_options(preset="both")
shadowText(x=1.5, y=3, col="white", "both", cex=cex)
shadowText(x=1.5, y=2.5, col="black", "both", cex=cex)
shadowText_options(preset="bold both")
shadowText(x=1.5, y=2, col="white", "bold both", cex=cex)
shadowText(x=1.5, y=1, col="black", "bold both", cex=cex)
shadowText(x=1.5, y=0.5, col="blue3", "bold both", cex=cex, font=2)
shadowText(x=1.5, y=0, col="indianred1", "bold both", cex=cex, font=2)
shadowText_options(preset="default")

See Also

Other jam plot functions: adjustAxisLabelMargins(), coordPresets(), decideMfrow(), drawLabels(), getPlotAspect(), groupedAxis(), imageByColors(), imageDefault(), minorLogTicksAxis(), nullPlot(), plotPolygonDensity(), plotRidges(), plotSmoothScatter(), shadowText(), showColors(), sqrtAxis(), usrBox()