X Version 11 (1 September 1988) XQueryColor(XS)
NAME
XQueryColor, XQueryColors, XLookupColor - obtain color
values
SYNTAX
XQueryColor(display, colormap, def_in_out)
Display *display;
Colormap colormap;
XColor *def_in_out;
XQueryColors(display, colormap, defs_in_out, ncolors)
Display *display;
Colormap colormap;
XColor defs_in_out[];
int ncolors;
Status XLookupColor(display, colormap, color_name,
exact_def_return, screen_def_return)
Display *display;
Colormap colormap;
char *color_name;
XColor *exact_def_return, *screen_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 definition array.
screen_def_return
Returns the closest RGB values provided by the
hardware.
DESCRIPTION
The XQueryColor function returns the RGB values for each
pixel in the XColor structures and sets the DoRed, DoGreen,
and DoBlue flags. The XQueryColors function returns the RGB
values for each pixel in the XColor structures and sets the
DoRed, DoGreen, and DoBlue flags.
XQueryColor and XQueryColors can generate BadColor and
BadValue errors.
The XLookupColor function looks up the string name of a
color with respect 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. You should
use the ISO Latin-1 encoding; uppercase and lowercase do not
matter. XLookupColor returns nonzero if the name existed in
the color database or zero if it did not exist.
DIAGNOSTICS
BadColor A value for a Colormap argument does not name a
defined Colormap.
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(XS), XCreateColormap(XS), XStoreColors(XS)
Xlib - C Language X Interface
(printed 2/12/90) (1 September 1988) XQueryColor(XS)