NAME
XPutImage, XGetImage, XGetSubImage - transfer images
SYNTAX
int
XPutImage(Display * display, Drawable d, GC gc, XImage *
image, int src_x, int src_y, int dest_x, int
dest_y, unsigned int width, unsigned int height);
XImage
*XGetImage(Display * display, Drawable d, int x, int
y, unsigned int width, unsigned int height, unsigned long
plane_mask, int format);
XImage
*XGetSubImage(Display * display, Drawable d, int x, int
y, unsigned int width, unsigned int height, unsigned long
plane_mask, int format, XImage * dest_image, int
dest_x, dest_y);
ARGUMENTS
- d
- Specifies the drawable.
- dest_image
- Specifies the destination image. and are the coordinates of
the subimage or which are relative to the origin of the destination
rectangle, specify its upper-left corner, and determine where the
subimage is placed in the destination image
- dest_x
-
- dest_y
- Specify the x and y coordinates, which are relative to the
origin of the drawable .
- display
- Specifies the connection to the X server.
- format
- Specifies the format for the image. You can pass
XYPixmap or ZPixmap.
- gc
- Specifies the GC.
- image
- Specifies the image you want combined with the
rectangle.
- plane_mask
- Specifies the plane mask.
- src_x
- Specifies the offset in X from the left edge of the image
defined by the XImage structure.
- src_y
- Specifies the offset in Y from the top edge of the image
defined by the XImage structure.
- width
-
- height
- Specify the width and height of the subimage, which
define the dimensions of the rectangle. and define the upper-left corner
of the rectangle
- x
-
- y
- Specify the x and y coordinates, which are relative to the
origin of the drawable .
DESCRIPTION
The
XPutImage function combines an image with a rectangle of the
specified drawable. The section of the image defined by the src_x, src_y,
width, and height arguments is drawn on the specified part of the drawable. If
XYBitmap format is used, the depth of the image must be one, or a
BadMatch error results. The foreground pixel in the GC defines the
source for the one bits in the image, and the background pixel defines the
source for the zero bits. For
XYPixmap and
ZPixmap, the depth of
the image must match the depth of the drawable, or a
BadMatch error
results.
If the characteristics of the image (for example, byte_order and bitmap_unit)
differ from what the server requires,
XPutImage automatically makes the
appropriate conversions.
This function uses these GC components: function, plane-mask, subwindow-mode,
clip-x-origin, clip-y-origin, and clip-mask. It also uses these GC
mode-dependent components: foreground and background.
XPutImage can generate
BadDrawable,
BadGC,
BadMatch,
and
BadValue errors.
The
XGetImage function returns a pointer to an
XImage structure.
This structure provides you with the contents of the specified rectangle of
the drawable in the format you specify. If the format argument is
XYPixmap, the image contains only the bit planes you passed to the
plane_mask argument. If the plane_mask argument only requests a subset of the
planes of the display, the depth of the returned image will be the number of
planes requested. If the format argument is
ZPixmap,
XGetImage
returns as zero the bits in all planes not specified in the plane_mask
argument. The function performs no range checking on the values in plane_mask
and ignores extraneous bits.
XGetImage returns the depth of the image to the depth member of the
XImage structure. The depth of the image is as specified when the
drawable was created, except when getting a subset of the planes in
XYPixmap format, when the depth is given by the number of bits set to 1
in plane_mask.
If the drawable is a pixmap, the given rectangle must be wholly contained within
the pixmap, or a
BadMatch error results. If the drawable is a window,
the window must be viewable, and it must be the case that if there were no
inferiors or overlapping windows, the specified rectangle of the window would
be fully visible on the screen and wholly contained within the outside edges
of the window, or a
BadMatch error results. Note that the borders of
the window can be included and read with this request. If the window has
backing-store, the backing-store contents are returned for regions of the
window that are obscured by noninferior windows. If the window does not have
backing-store, the returned contents of such obscured regions are undefined.
The returned contents of visible regions of inferiors of a different depth
than the specified window's depth are also undefined. The pointer cursor image
is not included in the returned contents. If a problem occurs,
XGetImage returns NULL.
XGetImage can generate
BadDrawable,
BadMatch, and
BadValue errors.
The
XGetSubImage function updates dest_image with the specified subimage
in the same manner as
XGetImage. If the format argument is
XYPixmap, the image contains only the bit planes you passed to the
plane_mask argument. If the format argument is
ZPixmap,
XGetSubImage returns as zero the bits in all planes not specified in
the plane_mask argument. The function performs no range checking on the values
in plane_mask and ignores extraneous bits. As a convenience,
XGetSubImage returns a pointer to the same
XImage structure
specified by dest_image.
The depth of the destination
XImage structure must be the same as that of
the drawable. If the specified subimage does not fit at the specified location
on the destination image, the right and bottom edges are clipped. If the
drawable is a pixmap, the given rectangle must be wholly contained within the
pixmap, or a
BadMatch error results. If the drawable is a window, the
window must be viewable, and it must be the case that if there were no
inferiors or overlapping windows, the specified rectangle of the window would
be fully visible on the screen and wholly contained within the outside edges
of the window, or a
BadMatch error results. If the window has
backing-store, then the backing-store contents are returned for regions of the
window that are obscured by noninferior windows. If the window does not have
backing-store, the returned contents of such obscured regions are undefined.
The returned contents of visible regions of inferiors of a different depth
than the specified window's depth are also undefined. If a problem occurs,
XGetSubImage returns NULL.
XGetSubImage can generate
BadDrawable,
BadGC,
BadMatch, and
BadValue errors.
DIAGNOSTICS
- BadDrawable
- A value for a Drawable argument does not name a defined
Window or Pixmap.
- BadGC
- A value for a GContext argument does not name a defined
GContext.
- 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.
SEE ALSO
Xlib - C Language X Interface