1 #include <u.h>
2 #include <libc.h>
3 #include <draw.h>
4
5 int
unloadimage(Image * i,Rectangle r,uchar * data,int ndata)6 unloadimage(Image *i, Rectangle r, uchar *data, int ndata)
7 {
8 int bpl, n, ntot, dy;
9 uchar *a;
10 Display *d;
11
12 if(!rectinrect(r, i->r)){
13 werrstr("unloadimage: bad rectangle");
14 return -1;
15 }
16 bpl = bytesperline(r, i->depth);
17 if(ndata < bpl*Dy(r)){
18 werrstr("unloadimage: buffer too small");
19 return -1;
20 }
21
22 d = i->display;
23 flushimage(d, 0); /* make sure subsequent flush is for us only */
24 ntot = 0;
25 while(r.min.y < r.max.y){
26 a = bufimage(d, 1+4+4*4);
27 if(a == 0){
28 werrstr("unloadimage: %r");
29 return -1;
30 }
31 dy = 8000/bpl;
32 if(dy <= 0){
33 werrstr("unloadimage: image too wide");
34 return -1;
35 }
36 if(dy > Dy(r))
37 dy = Dy(r);
38 a[0] = 'r';
39 BPLONG(a+1, i->id);
40 BPLONG(a+5, r.min.x);
41 BPLONG(a+9, r.min.y);
42 BPLONG(a+13, r.max.x);
43 BPLONG(a+17, r.min.y+dy);
44 if(flushimage(d, 0) < 0)
45 return -1;
46 n = read(d->fd, data+ntot, ndata-ntot);
47 if(n < 0)
48 return n;
49 ntot += n;
50 r.min.y += dy;
51 }
52 return ntot;
53 }
54