XCreateColormap(3X11) X11R5 XCreateColormap(3X11)NAME
XCreateColormap, XCopyColormapAndFree, XFreeColormap, XColor - create,
copy, or destroy colormaps and color structure
SYNTAX
Colormap XCreateColormap(display, w, visual, alloc)
Display *display;
Window w;
Visual *visual;
int alloc;
Colormap XCopyColormapAndFree(display, colormap)
Display *display;
Colormap colormap;
XFreeColormap(display, colormap)
Display *display;
Colormap colormap;
ARGUMENTS
alloc Specifies the colormap entries to be allocated. You can pass
or
colormap Specifies the colormap that you want to create, copy, set, or
destroy.
display Specifies the connection to the X server.
visual Specifies a visual type supported on the screen. If the vis‐
ual type is not one supported by the screen, a error results.
w Specifies the window on whose screen you want to create a
colormap.
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 allo‐
cate 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 speci‐
fied 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 col‐
ormap, and then all entries in the specified colormap are freed. If
the specified colormap was not created by the client with the alloca‐
tions to be moved are all those pixels and planes that have been allo‐
cated 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 func‐
tion has no effect on the default colormap for a screen. If the speci‐
fied 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 col‐
ormap 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 dis‐
play hardware. The server scales these values down to the range used
by the hardware. Black is represented by (0,0,0), white is represented
by (65535,65535,65535). In some functions, the flags member controls
which of the red, green, and blue members is used and can be the inclu‐
sive 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 ALSOXAllocColor(3X11), XChangeWindowAttributes(3X11), XCreateWindow(3X11),
XQueryColor(3X11), XStoreColors(3X11)
Xlib - C Language X Interface
XCreateColormap(3X11)