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XReadBitmapFile

Section: XLIB FUNCTIONS (3)
Updated: libX11 1.6.4
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NAME

XReadBitmapFile, XReadBitmapFileData, XWriteBitmapFile, XCreatePixmapFromBitmapData, XCreateBitmapFromData - manipulate bitmaps

SYNTAX

: int XReadBitmapFile(Display *display, Drawable d, char *filename, unsigned int *width_return, unsigned int *height_return, Pixmap *bitmap_return, int *x_hot_return, int *y_hot_return);
: int XReadBitmapFileData(char *filename, unsigned int *width_return, unsigned int *height_return, unsigned char *data_return, int *x_hot_return, int *y_hot_return);
: int XWriteBitmapFile(Display *display, char *filename, Pixmap bitmap, unsigned int width, unsigned int height, int x_hot, int y_hot);
: Pixmap XCreatePixmapFromBitmapData(Display *display, Drawable d, char *data, unsigned int width, unsigned int height, unsigned long fg, unsigned long bg, unsigned int depth);
: Pixmap XCreateBitmapFromData(Display *display, Drawable d, char *data, unsigned int width, unsigned int height);

ARGUMENTS

bitmap: Specifies the bitmap.
bitmap_return: Returns the bitmap that is created.
d: Specifies the drawable that indicates the screen.
data: Specifies the data in bitmap format.
data: Specifies the location of the bitmap data.
data_return: Returns the bitmap data.
depth: Specifies the depth of the pixmap.
display: Specifies the connection to the X server.
fg
bg: Specify the foreground and background pixel values to use.
filename: Specifies the file name to use. The format of the file name is operating-system dependent.
width
height: Specify the width and height.
width_return
height_return: Return the width and height values of the read in bitmap file.
x_hot
y_hot: Specify where to place the hotspot coordinates (or -1,-1 if none are present) in the file.
x_hot_return
y_hot_return: Return the hotspot coordinates.

DESCRIPTION

The XReadBitmapFile function reads in a file containing a bitmap. The file is parsed in the encoding of the current locale. The ability to read other than the standard format is implementation-dependent. If the file cannot be opened, XReadBitmapFile returns BitmapOpenFailed. If the file can be opened but does not contain valid bitmap data, it returns BitmapFileInvalid. If insufficient working storage is allocated, it returns BitmapNoMemory. If the file is readable and valid, it returns BitmapSuccess.

XReadBitmapFile returns the bitmap's height and width, as read from the file, to width_return and height_return. It then creates a pixmap of the appropriate size, reads the bitmap data from the file into the pixmap, and assigns the pixmap to the caller's variable bitmap. The caller must free the bitmap using XFreePixmap when finished. If name_x_hot and name_y_hot exist, XReadBitmapFile returns them to x_hot_return and y_hot_return; otherwise, it returns -1,-1.

XReadBitmapFile can generate BadAlloc and BadDrawable errors.

The XReadBitmapFileData function reads in a file containing a bitmap, in the same manner as XReadBitmapFile, but returns the data directly rather than creating a pixmap in the server. The bitmap data is returned in data_return; the client must free this storage when finished with it by calling XFree. The status and other return values are the same as for XReadBitmapFile.

The XWriteBitmapFile function writes a bitmap out to a file in the X Version 11 format. The name used in the output file is derived from the file name by deleting the directory prefix. The file is written in the encoding of the current locale. If the file cannot be opened for writing, it returns BitmapOpenFailed. If insufficient memory is allocated, XWriteBitmapFile returns BitmapNoMemory; otherwise, on no error, it returns BitmapSuccess. If x_hot and y_hot are not -1, -1, XWriteBitmapFile writes them out as the hotspot coordinates for the bitmap.

XWriteBitmapFile can generate BadDrawable and BadMatch errors.

The XCreatePixmapFromBitmapData function creates a pixmap of the given depth and then does a bitmap-format XPutImage of the data into it. The depth must be supported by the screen of the specified drawable, or a BadMatch error results.

XCreatePixmapFromBitmapData can generate BadAlloc and BadMatch errors.

The XCreateBitmapFromData function allows you to include in your C program (using #include) a bitmap file that was written out by XWriteBitmapFile (X version 11 format only) without reading in the bitmap file. The following example creates a gray bitmap:

#include "gray.bitmap"

Pixmap bitmap;
bitmap = XCreateBitmapFromData(display, window, gray_bits, gray_width, gray_height);

If insufficient working storage was allocated, XCreateBitmapFromData returns None. It is your responsibility to free the bitmap using XFreePixmap when finished.

XCreateBitmapFromData can generate a BadAlloc error.

DIAGNOSTICS

BadAlloc: The server failed to allocate the requested resource or server memory.
BadDrawable: A value for a Drawable argument does not name a defined Window or Pixmap.
BadMatch: An InputOnly window is used as a Drawable.