XQueryColoB(3x) — HP-UX 9.10

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

displaySpecifies a connection to an X server; returned from XOpenDisplay().

colormapSpecifies 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.

ncolorsSpecifies the number of XColor structures in the color definition array.

Description

XQueryColors() 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 member of each XColor structure in the colorcell_def array. The RGB values 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

BadColorInvalid colormap.

BadValuePixel not valid index into colormap. Note: if more than one pixel value is in error, the one reported is arbitrary.