Index for Section 3X11

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XCreateColormap(3X11)
X11R6
NAME
  XCreateColormap, XCopyColormapAndFree, XFreeColormap, XColor - create,
  copy, or destroy colormaps and color structure

SYNOPSIS
  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 AllocNone
      or AllocAll.

  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 visual type is
      not one supported by the screen, a BadMatch error results.

  w   Specifies the window on whose screen you want to create a colormap.

DESCRIPTION
  The XCreateColormap 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 GrayScale, PseudoColor, and DirectColor. For StaticGray,
  StaticColor, and TrueColor, the entries have defined values, but those
  values are specific to the visual and are not defined by X. For StaticGray,
  StaticColor, and TrueColor, alloc must be AllocNone, or a BadMatch error
  results. For the other visual classes, if alloc is AllocNone, 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 AllocAll, the entire colormap is allocated writable. The
  initial values of all allocated entries are undefined. For GrayScale and
  PseudoColor, the effect is as if an XAllocColorCells call returned all
  pixel values from zero to N - 1, where N is the colormap entries value in
  the specified visual. For DirectColor, the effect is as if an
  XAllocColorPlanes 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 XFreeColors.

  XCreateColormap can generate BadAlloc, BadMatch, BadValue, and BadWindow
  errors.

  The XCopyColormapAndFree 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 AllocAll, the new colormap is also created with AllocAll,
  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 AllocAll, the allocations to be
  moved are all those pixels and planes that have been allocated by the
  client using XAllocColor, XAllocNamedColor, XAllocColorCells, or
  XAllocColorPlanes and that have not been freed since they were allocated.

  XCopyColormapAndFree can generate BadAlloc and BadColor errors.

  The XFreeColormap 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
  XUninstallColormap). If the specified colormap is defined as the colormap
  for a window (by XCreateWindow, XSetWindowColormap, or
  XChangeWindowAttributes), XFreeColormap changes the colormap associated
  with the window to None and generates a ColormapNotify event. X does not
  define the colors displayed for a window with a colormap of None.

  XFreeColormap can generate a BadColor error.

STRUCTURES
  The XColor 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). 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 DoRed, DoGreen, and DoBlue.

DIAGNOSTICS
  BadAlloc
	  The server failed to allocate the requested resource or server
	  memory.

  BadColor
	  A value for a Colormap argument does not name a defined Colormap.

  BadMatch
	  An InputOnly window is used as a Drawable.

  BadMatch
	  Some argument or pair of arguments has the correct type and range
	  but fails to match in some other way required by the request.

  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.

  BadWindow
	  A value for a Window argument does not name a defined Window.

SEE ALSO
  XAllocColor(3X11), XChangeWindowAttributes(3X11), XCreateWindow(3X11),
  XQueryColor(3X11), XStoreColors(3X11)

  Xlib -- C Language X Interface

Index for Section 3X11

Alphabetical listing for X

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