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XQueryColor(3)			XLIB FUNCTIONS			XQueryColor(3)

NAME
       XQueryColor, XQueryColors, XLookupColor,	XParseColor - obtain color
       values

SYNTAX
       int XQueryColor(Display *display, Colormap colormap, XColor
	      *def_in_out);

       int XQueryColors(Display	*display, Colormap colormap, XColor
	      defs_in_out[], int ncolors);

       Status XLookupColor(Display *display, Colormap colormap,	char
	      *color_name, XColor *exact_def_return, XColor *screen_def_re-
	      turn);

       Status XParseColor(Display *display, Colormap colormap, char *spec,
	      XColor *exact_def_return);

ARGUMENTS
       colormap	 Specifies the colormap.

       color_name
		 Specifies the color name string (for example, red) whose
		 color definition structure you	want returned.

       def_in_out
		 Specifies and returns the RGB values for the pixel specified
		 in the	structure.

       defs_in_out
		 Specifies and returns an array	of color definition structures
		 for the pixel specified in the	structure.

       display	 Specifies the connection to the X server.

       exact_def_return
		 Returns the exact RGB values.

       ncolors	 Specifies the number of XColor	structures in the color	defi-
		 nition	array.

       screen_def_return
		 Returns the closest RGB values	provided by the	hardware.

       spec	 Specifies the color name string; case is ignored.

       exact_def_return
		 Returns the exact color value for later use and sets the
		 DoRed,	DoGreen, and DoBlue flags.

DESCRIPTION
       The XQueryColor function	returns	the current RGB	value for the pixel in
       the XColor structure and	sets the DoRed,	DoGreen, and DoBlue flags.
       The XQueryColors	function returns the RGB value for each	pixel in each
       XColor structure	and sets the DoRed, DoGreen, and DoBlue	flags in each
       structure.

       XQueryColor and XQueryColors can	generate BadColor and BadValue errors.

       The XLookupColor	function looks up the string name of a color with re-
       spect to	the screen associated with the specified colormap.  It returns
       both the	exact color values and the closest values provided by the
       screen with respect to the visual type of the specified colormap.  If
       the color name is not in	the Host Portable Character Encoding, the re-
       sult is implementation-dependent.  Use of uppercase or lowercase	does
       not matter.  XLookupColor returns nonzero if the	name is	resolved; oth-
       erwise, it returns zero.

       The XParseColor function	looks up the string name of a color with re-
       spect to	the screen associated with the specified colormap.  It returns
       the exact color value.  If the color name is not	in the Host Portable
       Character Encoding, the result is implementation-dependent.  Use	of up-
       percase or lowercase does not matter.  XParseColor returns nonzero if
       the name	is resolved; otherwise,	it returns zero.

       XLookupColor and	XParseColor can	generate BadColor error.

COLOR NAMES
       An RGB Device specification is identified by the	prefix ``rgb:''	and
       conforms	to the following syntax:

       rgb:_red_/_green_/_blue_

	   _red_, _green_, _blue_ := h | hh | hhh | hhhh
	   h :=	single hexadecimal digits (case	insignificant)

       Note that h indicates the value scaled in 4 bits, hh the	value scaled
       in 8 bits, hhh the value	scaled in 12 bits, and hhhh the	value scaled
       in 16 bits, respectively.

       For backward compatibility, an older syntax for RGB Device is sup-
       ported, but its continued use is	not encouraged.	 The syntax is an ini-
       tial sharp sign character followed by a numeric specification, in one
       of the following	formats:

       #RGB	       (4 bits each)
       #RRGGBB	       (8 bits each)
       #RRRGGGBBB      (12 bits	each)
       #RRRRGGGGBBBB   (16 bits	each)

       The R, G, and B represent single	hexadecimal digits.  When fewer	than
       16 bits each are	specified, they	represent the most significant bits of
       the value (unlike the ``rgb:'' syntax, in which values are scaled).
       For example, the	string ``#3a7''	is the same as ``#3000a0007000''.

       An RGB intensity	specification is identified by the prefix ``rgbi:''
       and conforms to the following syntax:

       rgbi:_red_/_green_/_blue_

       Note that red, green, and blue are floating-point values	between	0.0
       and 1.0,	inclusive.  The	input format for these values is an optional
       sign, a string of numbers possibly containing a decimal point, and an
       optional	exponent field containing an E or e followed by	a possibly
       signed integer string.

       The standard device-independent string specifications have the follow-
       ing syntax:

       CIEXYZ:_X_/_Y_/_Z_
       CIEuvY:_u_/_v_/_Y_
       CIExyY:_x_/_y_/_Y_
       CIELab:_L_/_a_/_b_
       CIELuv:_L_/_u_/_v_
       TekHVC:_H_/_V_/_C_

       All of the values (C, H,	V, X, Y, Z, a, b, u, v,	y, x) are floating-
       point values.  The syntax for these values is an	optional plus or minus
       sign, a string of digits	possibly containing a decimal point, and an
       optional	exponent field consisting of an	``E'' or ``e'' followed	by an
       optional	plus or	minus followed by a string of digits.

DIAGNOSTICS
       BadColor	 A value for a Colormap	argument does not name a defined Col-
		 ormap.

       BadValue	 Some numeric value falls outside the range of values accepted
		 by the	request.  Unless a specific range is specified for an
		 argument, the full range defined by the argument's type is
		 accepted.  Any	argument defined as a set of alternatives can
		 generate this error.

SEE ALSO
       XAllocColor(3), XCreateColormap(3), XStoreColors(3)
       Xlib - C	Language X Interface

X Version 11			 libX11	1.6.5			XQueryColor(3)

NAME | SYNTAX | ARGUMENTS | DESCRIPTION | COLOR NAMES | DIAGNOSTICS | SEE ALSO

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