X Drawables to Pixbufs

gdk_pixbuf_xlib_get_from_drawable ()

GdkPixbuf*  gdk_pixbuf_xlib_get_from_drawable
                                            (GdkPixbuf *dest,
                                             Drawable src,
                                             Colormap cmap,
                                             Visual *visual,
                                             int src_x,
                                             int src_y,
                                             int dest_x,
                                             int dest_y,
                                             int width,
                                             int height);

Transfers image data from a Gdk drawable and converts it to an RGB(A) representation inside a GdkPixbuf.

If the drawable src is a pixmap, then a suitable colormap must be specified, since pixmaps are just blocks of pixel data without an associated colormap. If the drawable is a window, the cmap argument will be ignored and the window's own colormap will be used instead.

If the specified destination pixbuf dest is NULL, then this function will create an RGB pixbuf with 8 bits per channel and no alpha, with the same size specified by the width and height arguments. In this case, the dest_x and dest_y arguments must be specified as 0, otherwise the function will return NULL. If the specified destination pixbuf is not NULL and it contains alpha information, then the filled pixels will be set to full opacity.

If the specified drawable is a pixmap, then the requested source rectangle must be completely contained within the pixmap, otherwise the function will return NULL.

If the specified drawable is a window, then it must be viewable, i.e. all of its ancestors up to the root window must be mapped. Also, the specified source rectangle must be completely contained within the window and within the screen. If regions of the window are obscured by noninferior windows, the contents of those regions are undefined. The contents of regions obscured by inferior windows of a different depth than that of the source window will also be undefined.