XQueryColors()XQueryColors()Name
XQueryColors – obtain RGB values for an array of colorcells.
Synopsis
XQueryColors(display, colormap, defs_in_out, ncolors)
Display *display;
Colormap colormap;
XColor defs_in_out[ncolors];
int ncolors;
Arguments
display Specifies a connection to an X server; returned from
XOpenDisplay().
colormap Specifies the ID of the colormap from which RGB values will
be retrieved.
defs_in_out
Specifies an array of XColor structures. In each one, pixel
is set to indicate which colorcell in the colormap to return,
and the RGB values in that colorcell are returned in red,
green, and blue.
ncolors Specifies the number of XColor structures in the color defi‐
nition array.
DescriptionXQueryColors() is similar to XQueryColor(), but it returns an array of
RGB values. It returns the RGB values in colormap colormap for each
colorcell corresponding to the pixel value specified in the pixel mem‐
ber of each XColor structure in the colorcell_def array. The RGB val‐
ues are returned in the red, green, and blue members of that same
structure, and sets the flags member in each XColor structure to (DoRed
DoGreen DoBlue).
For more information, see Volume One, Chapter 7, Color.
Structures
typedef struct {
unsigned long pixel;
unsigned short red, green, blue;
char flags; /* DoRed, DoGreen, DoBlue */
char pad;
} XColor;
Errors
BadColor Invalid colormap.
BadValue Pixel not valid index into colormap.
Note: if more than one pixel value is in error, the one reported is
arbitrary.
See AlsoXBlackPixel(), XWhitePixel(), XAllocColor(), XAllocColorCells(), XAl‐
locColorPlanes(), XAllocNamedColor(), XFreeColors(), XLookupColor(),
XParseColor(), XQueryColor(), XStoreColor(), XStoreColors(), XStore‐
NamedColor().
Xlib - Color Cells XQueryColors()
