Class (GI Struct)

Gdk-4.0 ▶ Gdk ▶ RGBA

Represents a color, in a way that is compatible with cairo’s notion of color.

Gdk.RGBA is a convenient way to pass colors around. It’s based on cairo’s way to deal with colors and mirrors its behavior. All values are in the range from 0.0 to 1.0 inclusive. So the color (0.0, 0.0, 0.0, 0.0) represents transparent black and (1.0, 1.0, 1.0, 1.0) is opaque white. Other values will be clamped to this range when drawing.

Index

Constructors

constructor

Properties

alpha blue green red $gtype

Methods

copy equal free hash is_clear is_opaque parse print to_string

Constructors

  • Parameters

    • Optionalproperties: Partial<{ alpha: number; blue: number; green: number; red: number }>

    Returns Gdk.RGBA

Properties

alpha: number
blue: number
green: number
red: number
$gtype: GType<Gdk.RGBA>

Methods

  • Checks if an rgba value is transparent.

    That is, drawing with the value would not produce any change.

    Returns boolean

    true if the rgba is clear

  • Checks if an rgba value is opaque.

    That is, drawing with the value will not retain any results from previous contents.

    Returns boolean

    true if the rgba is opaque

  • Parses a textual representation of a color.

    The string can be either one of:

    • A standard name (Taken from the CSS specification).
    • A hexadecimal value in the form “#rgb”, “#rrggbb”, “#rrrgggbbb” or ”#rrrrggggbbbb”
    • A hexadecimal value in the form “#rgba”, “#rrggbbaa”, or ”#rrrrggggbbbbaaaa”
    • 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)”
    • A HSL color in the form “hsl(h,s,l)”
    • A HSLA color in the form “hsla(h,s,l,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 percentage values in the range 0% to 100%, and a is a floating point value in the range 0 to 1. The range for “h” is 0 to 360, and “s”, “l” can be either numbers in the range 0 to 100 or percentages.

    Parameters

    • spec: string

      the string specifying the color

    Returns boolean

    true if the parsing succeeded

  • Returns a textual specification of rgba in the form rgb(r,g,b) or rgba(r,g,b,a), where “r”, “g”, “b” and “a” represent the red, green, blue and alpha values respectively. “r”, “g”, and “b” are represented as integers in the range 0 to 255, and “a” is represented as a floating point value in the range 0 to 1.

    These string forms are string forms that are supported by the CSS3 colors module, and can be parsed by Gdk.RGBA.parse.

    Note that this string representation may lose some precision, since “r”, “g” and “b” are represented as 8-bit integers. If this is a concern, you should use a different representation.

    Returns string

    A newly allocated text string