display_rgb: Plot RGB (RGBA) color composition in the PNG format.

display_rgbR Documentation

Plot RGB (RGBA) color composition in the PNG format.


Raster images are forced to be interpreted as color composition with 3 (RGB) or 4 (RGBA) channels. Values should be in the range between 0 and 255.


display_rgb(obj, ...)



Object of class ursaRaster or list of ursaRaster objects.


Passed to hierarchy of plotting functions:

  • compose_open

    • compose_design

  • compose_plot

    • panel_new

    • panel_raster

    • panel_decor

      • panel_graticule

      • panel_coastline

      • panel_scalebar

  • compose_close


If argument obj is list of ursaRaster objects (or object of class ursaStack) then obj is coerced to class ursaRaster ('stack' is coerced to 'brick').

Colorbar is not plotted.

By default, the created PNG has 24 bits per pixel. This is equal to parameter bpp=24 (compose_close). It is allow to specify other value, e.g., display_rgb(a,bpp=8).

By default, labels of gridlines are located in bottom and left sides of the panel with raster. This is equal to parameter margin=c(TRUE,TRUE,FALSE,FALSE) (panel_graticule). It is allow to specify other value, e.g., display_rgb(a,margin=T).

Currently, for color compositions the argument useRaster (panel_raster) is introduced to fix possible coordinate mismatch for Cairo-devices, but have never used.


Function returns NULL value.


Nikita Platonov platonov@sevin.ru

See Also

display, display_brick, display_stack


a <- ursa_dummy(nband=3)

ursa documentation built on Dec. 28, 2022, 2:18 a.m.