1XCreateColormap(3) XLIB FUNCTIONS XCreateColormap(3)
2
6 XCreateColormap, XCopyColormapAndFree, XFreeColormap, XColor - create,
7 copy, or destroy colormaps and color structure
8
10 Colormap XCreateColormap(Display *display, Window w, Visual *visual,
11 int alloc);
12 Colormap XCopyColormapAndFree(Display *display, Colormap colormap);
14 int XFreeColormap(Display *display, Colormap colormap);
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18 alloc Specifies the colormap entries to be allocated. You can pass
19 AllocNone or AllocAll.
20 colormap Specifies the colormap that you want to create, copy, set, or
22 destroy.
23 display Specifies the connection to the X server.
25 visual Specifies a visual type supported on the screen. If the vis‐
27 ual type is not one supported by the screen, a BadMatch error
28 results.
29 w Specifies the window on whose screen you want to create a
31 colormap.
32
34 The XCreateColormap function creates a colormap of the specified visual
35 type for the screen on which the specified window resides and returns
36 the colormap ID associated with it. Note that the specified window is
37 only used to determine the screen.
38 The initial values of the colormap entries are undefined for the visual
40 classes GrayScale, PseudoColor, and DirectColor. For StaticGray, Stat‐
41 icColor, and TrueColor, the entries have defined values, but those val‐
42 ues are specific to the visual and are not defined by X. For Stat‐
43 icGray, StaticColor, and TrueColor, alloc must be AllocNone, or a Bad‐
44 Match error results. For the other visual classes, if alloc is Alloc‐
45 None, the colormap initially has no allocated entries, and clients can
46 allocate them. For information about the visual types, see section
47 3.1.
48 If alloc is AllocAll, the entire colormap is allocated writable. The
50 initial values of all allocated entries are undefined. For GrayScale
51 and PseudoColor, the effect is as if an XAllocColorCells call returned
52 all pixel values from zero to N - 1, where N is the colormap entries
53 value in the specified visual. For DirectColor, the effect is as if an
54 XAllocColorPlanes call returned a pixel value of zero and red_mask,
55 green_mask, and blue_mask values containing the same bits as the corre‐
56 sponding masks in the specified visual. However, in all cases, none of
57 these entries can be freed by using XFreeColors.
58 XCreateColormap can generate BadAlloc, BadMatch, BadValue, and BadWin‐
60 dow errors.
61 The XCopyColormapAndFree function creates a colormap of the same visual
63 type and for the same screen as the specified colormap and returns the
64 new colormap ID. It also moves all of the client's existing allocation
65 from the specified colormap to the new colormap with their color values
66 intact and their read-only or writable characteristics intact and frees
67 those entries in the specified colormap. Color values in other entries
68 in the new colormap are undefined. If the specified colormap was cre‐
69 ated by the client with alloc set to AllocAll, the new colormap is also
70 created with AllocAll, all color values for all entries are copied from
71 the specified colormap, and then all entries in the specified colormap
72 are freed. If the specified colormap was not created by the client
73 with AllocAll, the allocations to be moved are all those pixels and
74 planes that have been allocated by the client using XAllocColor, XAl‐
75 locNamedColor, XAllocColorCells, or XAllocColorPlanes and that have not
76 been freed since they were allocated.
77 XCopyColormapAndFree can generate BadAlloc and BadColor errors.
79 The XFreeColormap function deletes the association between the colormap
81 resource ID and the colormap and frees the colormap storage. However,
82 this function has no effect on the default colormap for a screen. If
83 the specified colormap is an installed map for a screen, it is unin‐
84 stalled (see XUninstallColormap). If the specified colormap is defined
85 as the colormap for a window (by XCreateWindow, XSetWindowColormap, or
86 XChangeWindowAttributes), XFreeColormap changes the colormap associated
87 with the window to None and generates a ColormapNotify event. X does
88 not define the colors displayed for a window with a colormap of None.
89 XFreeColormap can generate a BadColor error.
91
93 The XColor structure contains:
94 typedef struct {
96 unsigned long pixel; /* pixel value */
97 unsigned short red, green, blue; /* rgb values */
98 char flags; /* DoRed, DoGreen, DoBlue */
99 char pad;
100 } XColor;
101 The red, green, and blue values are always in the range 0 to 65535 in‐
103 clusive, independent of the number of bits actually used in the display
104 hardware. The server scales these values down to the range used by the
105 hardware. Black is represented by (0,0,0), and white is represented by
106 (65535,65535,65535). In some functions, the flags member controls
107 which of the red, green, and blue members is used and can be the inclu‐
108 sive OR of zero or more of DoRed, DoGreen, and DoBlue.
109
111 BadAlloc The server failed to allocate the requested resource or
112 server memory.
113 BadColor A value for a Colormap argument does not name a defined Col‐
115 ormap.
116 BadMatch An InputOnly window is used as a Drawable.
118 BadMatch Some argument or pair of arguments has the correct type and
120 range but fails to match in some other way required by the
121 request.
122 BadValue Some numeric value falls outside the range of values accepted
124 by the request. Unless a specific range is specified for an
125 argument, the full range defined by the argument's type is
126 accepted. Any argument defined as a set of alternatives can
127 generate this error.
128 BadWindow A value for a Window argument does not name a defined Window.
130
132 XAllocColor(3), XChangeWindowAttributes(3), XCreateWindow(3), XQuery‐
133 Color(3), XStoreColors(3)
134 Xlib - C Language X Interface
135X Version 11 libX11 1.8.1 XCreateColormap(3)