XCreateColormap
NAME
XCreateColormap, XCopyColormapAndFree, XFreeColormap, XColor - create, copy, or destroy colormaps and color structure
SYNTAX
Colormap XCreateColormap\^(\^Display *display\^, Window w\^,
Visual *visual\^, int alloc\^,);
Colormap XCopyColormapAndFree\^(\^Display *display\^, Colormap
colormap\^);
int XFreeColormap\^(\^Display *display\^, Colormap colormap\^);
ARGUMENTS
alloc
Specifies the colormap entries to be allocated.
You can pass
or
colormap
Specifies the colormap .
display
Specifies the connection to the X server.
visual
Specifies a visual type supported on the screen.
If the visual type is not one supported by the screen,
a
error results.
w
Specifies the window .
DESCRIPTION
The
function creates a colormap of the specified visual type for the screen
on which the specified window resides and returns the colormap ID
associated with it.
Note that the specified window is only used to determine the screen.
The initial values of the colormap entries are undefined for the
visual classes
and
For
and
the entries have defined values,
but those values are specific to the visual and are not defined by X.
For
and
alloc must be
or a
error results.
For the other visual classes,
if alloc is
the colormap initially has no allocated entries,
and clients can allocate them.
For information about the visual types,
see section 3.1.
If alloc is
the entire colormap is allocated writable.
The initial values of all allocated entries are undefined.
For
and
the effect is as if an
call returned all pixel values from zero to N - 1,
where N is the colormap entries value in the specified visual.
For
the effect is as if an
call returned a pixel value of zero and red_mask, green_mask,
and blue_mask values containing the same bits as the corresponding
masks in the specified visual.
However, in all cases,
none of these entries can be freed by using
can generate
and
errors.
The
function creates a colormap of the same visual type and for the same screen
as the specified colormap and returns the new colormap ID.
It also moves all of the client's existing allocation from the specified
colormap to the new colormap with their color values intact
and their read-only or writable characteristics intact and frees those entries
in the specified colormap.
Color values in other entries in the new colormap are undefined.
If the specified colormap was created by the client with alloc set to
the new colormap is also created with
all color values for all entries are copied from the specified colormap,
and then all entries in the specified colormap are freed.
If the specified colormap was not created by the client with
the allocations to be moved are all those pixels and planes
that have been allocated by the client using
or
and that have not been freed since they were allocated.
can generate
and
errors.
The
function deletes the association between the colormap resource ID
and the colormap and frees the colormap storage.
However, this function has no effect on the default colormap for a screen.
If the specified colormap is an installed map for a screen,
it is uninstalled (see
If the specified colormap is defined as the colormap for a window (by
or
changes the colormap associated with the window to
and generates a
event.
X does not define the colors displayed for a window with a colormap of
can generate a
error.
STRUCTURES
The
structure contains:
typedef struct {
unsigned long pixel; / pixel value */
unsigned short red, green, blue; / rgb values */
char flags; / DoRed, DoGreen, DoBlue */
char pad;
} XColor;
The red, green, and blue values are always in the range 0 to 65535
inclusive, independent of the number of bits actually used in the
display hardware.
The server scales these values down to the range used by the hardware.
Black is represented by (0,0,0),
and white is represented by (65535,65535,65535).
N Color
In some functions,
the flags member controls which of the red, green, and blue members is used
and can be the inclusive OR of zero or more of
and
DIAGNOSTICS
The server failed to allocate the requested resource or server memory.
A value for a Colormap argument does not name a defined Colormap.
An
window is used as a Drawable.
Some argument or pair of arguments has the correct type and range but fails
to match in some other way required by the request.
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.
A value for a Window argument does not name a defined Window.
SEE ALSO
XAllocColor(3X11),
XChangeWindowAttributes(3X11),
XCreateWindow(3X11),
XQueryColor(3X11),
XStoreColors(3X11)
