when a replicated source image with a clipr with clipr.min > Pt(0, 0),
drawclip() would properly translate the src->clipr on the dstr
but then clamp the source rectangle back on src->r.
while traversing down multiple layers, this would cause the translation to
be applied multiple times to the dst rectangle giving the wrong image result.
this change adds a new drawclipnorepl() function that avoids the clamping
of source and mask rectangles to src->r and mask->r. this is then used in
libmemlayer.
the final memimagedraw() call will call drawclip() which will do the final
claming.
a testcase is provided:
#include <u.h>
#include <libc.h>
#include <draw.h>
Image *blue;
Image *red;
void
main(int, char *argv[])
{
Image *i;
if(initdraw(nil, nil, argv[0]) < 0)
sysfatal("initdraw: %r");
i = allocimage(display, screen->r, screen->chan, 1, DWhite);
red = allocimage(display, Rect(0,0,1,1), screen->chan, 1, DRed);
blue = allocimage(display, Rect(0,0,1,1), screen->chan, 1, DPaleblue);
replclipr(red, 1, Rect(10, 10, 110, 110));
replclipr(blue, 1, Rect(11, 11, 111, 111));
/* draw on non-layer, works correctly */
draw(i, i->r, red, nil, ZP);
draw(i, i->r, blue, nil, ZP);
draw(screen, screen->r, i, nil, i->r.min);
flushimage(display, 1);
/* draw on (screen) layer is too far to the right */
draw(screen, screen->r, red, nil, ZP);
draw(screen, screen->r, blue, nil, ZP);
flushimage(display, 1);
for(;;){
sleep(1000);
}
}
the process is *NOT* allowed to exit after a srvrelease() as
it still holds a reference (srv->rref) preventing the srv
from beging freed/ended (listensrv) before srvacquire().
Bread() always reads exactly nbytes of data if it can. only
when it reaches end of file or an error it will return less.
so the Breadn() function that was introduced has been removed.
sorry for the confusion.
