bm_clamp {bittermelon}

Clamp bitmap values

Description

bm_clamp() “clamps” bm_bitmap() integers that lie outside an interval. The default coerces a multiple-integer-valued bitmap into a binary bitmap (as expected by most bitmap font formats). For pixmap objects non-background pixels are all coerced to a single value.

Usage

bm_clamp(x, ...)

## S3 method for class 'bm_bitmap'
bm_clamp(x, lower = 0L, upper = 1L, value = upper, ...)

## S3 method for class 'bm_list'
bm_clamp(x, ...)

## S3 method for class 'bm_pixmap'
bm_clamp(x, value = col2hex("black"), bg = col2hex("transparent"), ...)

## S3 method for class ''magick-image''
bm_clamp(x, value = "black", bg = "transparent", ...)

## S3 method for class 'nativeRaster'
bm_clamp(x, value = col2int("black"), bg = col2int("transparent"), ...)

## S3 method for class 'raster'
bm_clamp(x, value = "black", bg = "transparent", ...)

Arguments

x

Either a bm_bitmap(), bm_font(), bm_list(), "magick-image", "nativeRaster", bm_pixmap(), or "raster" object.

...

Additional arguments to be passed to or from methods.

lower

Integer value. Any value below lower will be clamped.

upper

Integer value. Any value above upper will be clamped.

value

Integer vector of length one or two of replacement value(s). If value is length one any values above upper are replaced by value while those below lower are replaced by lower. If value is length two any values above upper are replaced by value[2] and any values below lower are replaced by value[1]. For pixmap objects indicate requested non-background color.

bg

Bitmap background value.

Value

Depending on x either a bm_bitmap(), bm_font(), bm_list(), magick-image, "nativeRaster", bm_pixmap(), or raster object.

Examples

plus_sign <- matrix(0L, nrow = 9L, ncol = 9L)
plus_sign[5L, 3:7] <- 2L
plus_sign[3:7, 5L] <- 2L
plus_sign_glyph <- bm_bitmap(plus_sign)
print(plus_sign_glyph)

plus_sign_clamped <- bm_clamp(plus_sign_glyph)
print(plus_sign_clamped)

tulip <- farming_crops_16x16()$tulip$portrait
if (cli::is_utf8_output() && cli::num_ansi_colors() >= 8L) {
  print(bm_clamp(tulip, "magenta"), compress = "v")
}