XcmsStoreColor

Section: XLIB FUNCTIONS (3)
Updated: libX11 1.7.0
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NAME

XcmsStoreColor, XcmsStoreColors - set colors

SYNTAX

: Status XcmsStoreColor(Display *display, Colormap colormap, XcmsColor *color);
: Status XcmsStoreColors(Display *display, Colormap colormap, XcmsColor *colors, unsigned ncolors, Bool *compression_flags_return);

ARGUMENTS

display: Specifies the connection to the X server.
color: Specifies the color cell and the color to store. Values specified in this XcmsColor structure remain unchanged on return.
colors: Specifies the color specification array of XcmsColor structures, each specifying a color cell and the color to store in that cell. Values specified in the array remain unchanged upon return.
colormap: Specifies the colormap.
compression_flags_return: Returns an array of Boolean values indicating compression status. If a non-NULL pointer is supplied, each element of the array is set to True if the corresponding color was compressed and False otherwise. Pass NULL if the compression status is not useful.
ncolors: Specifies the number of XcmsColor structures in the color-specification array.

DESCRIPTION

The XcmsStoreColor function converts the color specified in the XcmsColor structure into RGB values. It then uses this RGB specification in an XColor structure, whose three flags DoGreen, and DoBlue) are set, in a call to XStoreColor to change the color cell specified by the pixel member of the XcmsColor structure. This pixel value must be a valid index for the specified colormap, and the color cell specified by the pixel value must be a read/write cell. If the pixel value is not a valid index, a BadValue error results. If the color cell is unallocated or is allocated read-only, a BadAccess error results. If the colormap is an installed map for its screen, the changes are visible immediately.

Note that XStoreColor has no return value; therefore, an XcmsSuccess return value from this function indicates that the conversion to RGB succeeded and the call to XStoreColor was made. To obtain the actual color stored, use XcmsQueryColor. Because of the screen's hardware limitations or gamut compression, the color stored in the colormap may not be identical to the color specified.

XcmsStoreColor can generate BadAccess, BadColor, and BadValue errors.

The XcmsStoreColors function converts the colors specified in the array of XcmsColor structures into RGB values and then uses these RGB specifications in XColor structures, whose three flags DoGreen, and DoBlue) are set, in a call to XStoreColors to change the color cells specified by the pixel member of the corresponding XcmsColor structure. Each pixel value must be a valid index for the specified colormap, and the color cell specified by each pixel value must be a read/write cell. If a pixel value is not a valid index, a BadValue error results. If a color cell is unallocated or is allocated read-only, a BadAccess error results. If more than one pixel is in error, the one that gets reported is arbitrary. If the colormap is an installed map for its screen, the changes are visible immediately.

Note that XStoreColors has no return value; therefore, an XcmsSuccess return value from this function indicates that conversions to RGB succeeded and the call to XStoreColors was made. To obtain the actual colors stored, use XcmsQueryColors. Because of the screen's hardware limitations or gamut compression, the colors stored in the colormap may not be identical to the colors specified.

XcmsStoreColors can generate BadAccess, BadColor, and BadValue errors.

DIAGNOSTICS

BadAccess: A client attempted to free a color map entry that it did not already allocate.
BadAccess: A client attempted to store into a read-only color map entry.
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.