1 #include <u.h>
2 #include <libc.h>
3 #include <draw.h>
4 #include <memdraw.h>
5 #include <memlayer.h>
6 
7 int
8 memunload(Memimage *src, Rectangle r, uchar *data, int n)
9 {
10 	Memimage *tmp;
11 	Memlayer *dl;
12 	Rectangle lr;
13 	int dx;
14 
15     Top:
16 	dl = src->layer;
17 	if(dl == nil)
18 		return unloadmemimage(src, r, data, n);
19 
20 	/*
21  	 * Convert to screen coordinates.
22 	 */
23 	lr = r;
24 	r.min.x += dl->delta.x;
25 	r.min.y += dl->delta.y;
26 	r.max.x += dl->delta.x;
27 	r.max.y += dl->delta.y;
28 	dx = dl->delta.x&(7/src->depth);
29 	if(dl->clear && dx==0){
30 		src = dl->screen->image;
31 		goto Top;
32 	}
33 
34 	/*
35 	 * src is an obscured layer or data is unaligned
36 	 */
37 	if(dl->save && dx==0){
38 		if(dl->refreshfn != 0)
39 			return -1;	/* can't unload window if it's not Refbackup */
40 		if(n > 0)
41 			memlhide(src, r);
42 		n = unloadmemimage(dl->save, lr, data, n);
43 		return n;
44 	}
45 	tmp = allocmemimage(lr, src->chan);
46 	if(tmp == nil)
47 		return -1;
48 	memdraw(tmp, lr, src, lr.min, nil, lr.min, S);
49 	n = unloadmemimage(tmp, lr, data, n);
50 	freememimage(tmp);
51 	return n;
52 }