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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,	 _Xconst  char
	      *color_name,  XColor  *exact_def_return,	XColor *screen_def_re-
	      turn);

       Status XParseColor(Display *display, Colormap  colormap,	 _Xconst  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 con-
       forms 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  op-
       tional 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	1.6.12			XQueryColor(3)

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

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