xref: /plan9/sys/src/cmd/unix/drawterm/libmemlayer/load.c (revision 7dd7cddf99dd7472612f1413b4da293630e6b1bc)
1 #include "../lib9.h"
2 
3 #include "../libdraw/draw.h"
4 #include "../libmemdraw/memdraw.h"
5 #include "../libmemlayer/memlayer.h"
6 
7 int
8 memload(Memimage *dst, Rectangle r, uchar *data, int n, int iscompressed)
9 {
10 	int (*loadfn)(Memimage*, Rectangle, uchar*, int);
11 	Memimage *tmp;
12 	Memlayer *dl;
13 	Rectangle lr;
14 	int dx;
15 
16 	loadfn = loadmemimage;
17 	if(iscompressed)
18 		loadfn = cloadmemimage;
19 
20     Top:
21 	dl = dst->layer;
22 	if(dl == nil)
23 		return loadfn(dst, r, data, n);
24 
25 	/*
26  	 * Convert to screen coordinates.
27 	 */
28 	lr = r;
29 	r.min.x += dl->delta.x;
30 	r.min.y += dl->delta.y;
31 	r.max.x += dl->delta.x;
32 	r.max.y += dl->delta.y;
33 	dx = dl->delta.x&(7/dst->depth);
34 	if(dl->clear && dx==0){
35 		dst = dl->screen->image;
36 		goto Top;
37 	}
38 
39 	/*
40 	 * dst is an obscured layer or data is unaligned
41 	 */
42 	if(dl->save && dx==0){
43 		n = loadfn(dl->save, lr, data, n);
44 		if(n > 0)
45 			memlexpose(dst, r);
46 		return n;
47 	}
48 	tmp = allocmemimage(lr, dst->chan);
49 	if(tmp == nil)
50 		return -1;
51 	n = loadfn(tmp, lr, data, n);
52 	memdraw(dst, lr, tmp, lr.min, nil, lr.min);
53 	freememimage(tmp);
54 	return n;
55 }
56