Re: [9fans] acme line wrap bug

[erik quanstrom <quanstro@quanstro.net>]

On Fri Feb 12 11:49:37 EST 2010, rsc@swtch.com wrote:
> > acme doesn't always clear the right margin to compensate for
> > the different amount of right-margin slop due to different
> > character widths.  in this case ">" is very wide and won't fit
> > in the space that "n" did.  so the n is mistakenly shown where
> > it shouldn't be.
> >
> > between the two pngs, the text "has gone" was cut.
>
> long time bug.  patch?

this has been effective for me:

; diff -c /n/dump/2010/0212/sys/src/libframe/frdelete.c frdelete.c
/n/dump/2010/0212/sys/src/libframe/frdelete.c:10,16 - frdelete.c:10,16
  {
  	Point pt0, pt1, ppt0;
  	Frbox *b;
- 	int n0, n1, n;
+ 	int n0, n1, n, w0;
  	ulong cn1;
  	Rectangle r;
  	int nn0;
/n/dump/2010/0212/sys/src/libframe/frdelete.c:53,58 - frdelete.c:53,59
  		r.max = pt0;
  		r.max.y += f->font->height;
  		if(b->nrune > 0){
+ 			w0 = b->wid;
  			if(n != b->nrune){
  				_frsplitbox(f, n1, n);
  				b = &f->box[n1];
/n/dump/2010/0212/sys/src/libframe/frdelete.c:60,65 - frdelete.c:61,74
  			r.max.x += b->wid;
  			draw(f->b, r, f->b, nil, pt1);
  			cn1 += b->nrune;
+
+ 			/* blank remainder of line */
+ 			r.min.x = r.max.x;
+ 			r.max.x += w0 - b->wid;
+ 			if(r.max.x > f->r.max.x)
+ 				r.max.x = f->r.max.x;
+ 			if(r.max.x != r.min.x)
+ 				draw(f->b, r, f->cols[BACK], nil, r.min);
  		}else{
  			r.max.x += _frnewwid0(f, pt0, b);
  			if(r.max.x > f->r.max.x)

- erik