xquerycoloa(3) [hpux man page]
XQueryColor() XQueryColor() Name XQueryColor - obtain the RGB values and flags for a specified colorcell. Synopsis XQueryColor(display, colormap, def_in_out) Display *display; Colormap colormap; XColor *def_in_out; 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. def_in_out Specifies the pixel value and returns the RGB contents of that colorcell. Description XQueryColor() returns the RGB values in colormap colormap for the colorcell corresponding to the pixel value specified in the pixel member of the XColor structure def_in_out. The RGB values are returned in the red, green, and blue members of that structure, and the flags mem- ber of that structure is set to (DoRed DoGreen DoBlue). The values returned for an unallocated entry are undefined. 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. See Also XBlackPixel(), XWhitePixel(), XAllocColor(), XAllocColorCells(), XAllocColorPlanes(), XAllocNamedColor(), XFreeColors(), XLookupColor(), XParseColor(), XQueryColors(), XStoreColor(), XStoreColors(), XStoreNamedColor(). Xlib - Color Cells XQueryColor()
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XAllocNamedColor() XAllocNamedColor() Name XAllocNamedColor - allocate a read-only colorcell from color name. Synopsis Status XAllocNamedColor(display, colormap, color_name, screen_def_return, exact_def_return) Display *display; Colormap colormap; char *color_name; XColor *screen_def_return; XColor *exact_def_return; Arguments display Specifies a connection to an X server; returned from XOpenDisplay(). colormap Specifies the ID of the colormap in which the colorcell will be allocated. color_name Specifies the color name string (for example, "red") you want. Uppercase or lowercase does not matter. If the color name is not in the Host Portable Character Encoding, the result is implementation-dependent. screen_def_return Returns the pixel value and RGB values actually used in the colormap. This is the closest color supported by the hardware. exact_def_return Returns the exact RGB values from the database corresponding to the color_name supplied. Returns Zero on failure, non-zero on success. Description XAllocNamedColor() determines the RGB values for the specified color_name from the color database, and then allocates a read-only colorcell with the closest color available, as described under XAllocColor(). Like XAllocColor, XAllocNamedColor() acts differently on static and dynamic visuals. On PseudoColor, DirectColor, and GrayScale visuals, XAllocNamedColor() fails if there are no unallocated colorcells and no allocated read-only colorcell exactly matches the database defini- tion of the requested color. On StaticColor, TrueColor, and StaticGray visuals, XAllocNamedColor() returns the closest RGB values (to the database definition of the requested color) available in the colormap. Both the database definition of the color, and the color actually allocated are returned. XAllocNamedColor() returns a Status of zero if color_name was not found in the database or if the color could not be allocated. The func- tion returns non-zero when it succeeds. For more information, see Volume One, Chapter 7, Color. Errors BadColor colormap is invalid. Structures typedef struct { unsigned long pixel; unsigned short red, green, blue; char flags; /* DoRed, DoGreen, DoBlue */ char pad; } XColor; See Also XBlackPixel(), XWhitePixel(), XAllocColor(), XAllocColorCells(), XAllocColorPlanes(), XFreeColors(), XLookupColor(), XParseColor(), XQuery- Color(), XQueryColors(), XStoreColor(), XStoreColors(), XStoreNamedColor(). Xlib - Color Cells XAllocNamedColor()