XcmsQueryColor(3X11) XLIB FUNCTIONS XcmsQueryColor(3X11)NAME
XcmsQueryColor, XcmsQueryColors, XcmsLookupColor - obtain
color values
SYNTAX
Status XcmsQueryColor(display, colormap, color_in_out,
result_format)
Display *display;
Colormap colormap;
XcmsColor *color_in_out;
XcmsColorFormat result_format;
Status XcmsQueryColors(display, colormap, colors_in_out,
ncolors, result_format)
Display *display;
Colormap colormap;
XcmsColor colors_in_out[];
unsigned int ncolors;
XcmsColorFormat result_format;
Status XcmsLookupColor(display, colormap, color_string,
color_exact_return, color_screen_return,
result_format)
Display *display;
Colormap colormap;
char *color_string;
XcmsColor *color_exact_return, *color_screen_return;
XcmsColorFormat result_format;
ARGUMENTS
display Specifies the connection to the X server.
colormap Specifies the colormap.
color_exact_return
Returns the color specification parsed from the
color string or parsed from the corresponding
string found in a color-name database.
color_in_out
Specifies the pixel member that indicates the
color cell to query. The color specification
stored for the color cell is returned in this
XcmsColor structure.
color_screen_return
Returns the color that can be reproduced on the
screen.
color_string
Specifies the color string.
result_format
Specifies the color format for the returned
X Version 11 Release 6.4 1
XcmsQueryColor(3X11) XLIB FUNCTIONS XcmsQueryColor(3X11)
color specifications (color_screen_return and
color_exact_return arguments). If the format is
XcmsUndefinedFormat and the color string con-
tains a numerical color specification, the spec-
ification is returned in the format used in that
numerical color specification. If the format is
XcmsUndefinedFormat and the color string con-
tains a color name, the specification is
returned in the format used to store the color
in the database.
ncolors Specifies the number of XcmsColor structures in
the color-specification array.
DESCRIPTION
The XcmsQueryColor function obtains the RGB value for the
pixel value in the pixel member of the specified XcmsColor
structure and then converts the value to the target format
as specified by the result_format argument. If the pixel
is not a valid index in the specified colormap, a BadValue
error results. The XcmsQueryColors function obtains the
RGB values for pixel values in the pixel members of Xcms-
Color structures and then converts the values to the tar-
get format as specified by the result_format argument. If
a pixel is not a valid index into the specified colormap,
a BadValue error results. If more than one pixel is in
error, the one that gets reported is arbitrary.
XcmsQueryColor and XcmsQueryColors can generate BadColor
and BadValue errors.
The XcmsLookupColor function looks up the string name of a
color with respect to the screen associated with the spec-
ified 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. The values
are returned in the format specified by result_format. If
the color name is not in the Host Portable Character
Encoding, the result is implementation-dependent. Use of
uppercase or lowercase does not matter. XcmsLookupColor
returns XcmsSuccess or XcmsSuccessWithCompression if the
name is resolved; otherwise, it returns XcmsFailure. If
XcmsSuccessWithCompression is returned, the color specifi-
cation returned in color_screen_return is the result of
gamut compression.
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 spe-
cific range is specified for an argument, the
full range defined by the argument's type is
X Version 11 Release 6.4 2
XcmsQueryColor(3X11) XLIB FUNCTIONS XcmsQueryColor(3X11)
accepted. Any argument defined as a set of
alternatives can generate this error.
SEE ALSOXcmsAllocColor(3X11), XcmsStoreColor(3X11), XQuery-
Color(3X11)
Xlib - C Language X Interface
X Version 11 Release 6.4 3
