Package: gdk

Function gdk:rgba-parse

Lambda List

gdk:rgba-parse (str)

Arguments

str -- a string specifying the color

Return Value

The newly created gdk:rgba color with the filled in values, or nil.

Details

Parses a textual representation of a color, and returns a RGBA instance filling in the red, green, blue and alpha fields. If the given textual representation is not recognized, nil is returned. The string can be either one of:
  • A standard name taken from the X11 rgb.txt file.
  • A hex value in the form rgb, rrggbb, rrrgggbbb or rrrrggggbbbb.
  • A RGB color in the form rgb(r,g,b). In this case the color will have full opacity.
  • A RGBA color in the form rgba(r,g,b,a).
Where r, g, b and a are respectively the red, green, blue and alpha color values. In the last two cases, r, g and b are either integers in the range 0 to 255 or precentage values in the range 0% to 100%, and a is a floating point value in the range 0.0 to 1.0.

Examples

(gdk:rgba-parse "LightGreen")
=> #S(GDK-RGBA :RED 0.5647059
               :GREEN 0.93333334
               :BLUE 0.5647059
               :ALPHA 1.0)
(gdk:rgba-parse "#90ee90")
=> #S(GDK-RGBA :RED 0.5647059
               :GREEN 0.93333334
               :BLUE 0.5647059
               :ALPHA 1.0)
(gdk:rgba-parse "unknown") => NIL    
 

See also

2025-1-11