Re: Question about display engine

[Ergus]

On Mon, Oct 14, 2019 at 12:01:46AM +0300, Eli Zaretskii wrote:
> > Date: Sun, 13 Oct 2019 21:38:36 +0200
> > From: Ergus <address@hidden>
> > Cc: address@hidden, address@hidden
> >
> > (gdb) p it->sp
> > $1 = 0
> > (gdb) p it->method
> > $2 = GET_FROM_C_STRING
>
> If we are producing glyphs from a C string, then faces should not be
> used at all, because C strings cannot have faces.
>
> So you should to condition the call to face_at_pos on something like
>
>  it->s == NULL
Hi:

This have fixed the issue, I understand now what was happening. Should I
merge into master now? maybe you should close the related issues then
right?.


> because there can not be any face on any position of a C string.
>
> > (gdb) pgrowx it->glyph_row
> > TEXT: 85 glyphs
> >   0    0: CHAR[-] str=0x4fab1a8f[0] blev=0,btyp=L w=1 a+d=0+0 face=1
> >   1    1: CHAR[U] str=0x4fab18f0[1] blev=0,btyp=L w=1 a+d=0+0 face=1
> >   2    2: CHAR[U] str=0x4fab18f0[1] blev=0,btyp=L w=1 a+d=0+0 face=1
> >   3    3: CHAR[U] str=0x4fab18f0[1] blev=0,btyp=L w=1 a+d=0+0 face=1
> >   4    4: CHAR[:] str=0xf2787f0[0] blev=0,btyp=L w=1 a+d=0+0 face=1
> >   5    5: CHAR[%] str=0x4faaee54[1] blev=0,btyp=L w=1 a+d=0+0 face=1
> >   6    6: CHAR[%] str=0x4faaede4[1] blev=0,btyp=L w=1 a+d=0+0 face=1
> >   7    7: CHAR[-] str=0x4fab1721[1] blev=0,btyp=L w=1 a+d=0+0 face=1
> >   8    8: CHAR[-] str=0x4fa9d9a8[0] blev=0,btyp=L w=1 a+d=0+0 face=1
> >   9    9: CHAR[F] str=0x4fa9d9a8[2] blev=0,btyp=L w=1 a+d=0+0 face=1
> >  10   10: CHAR[1] str=0x4fa9d9a8[2] blev=0,btyp=L w=1 a+d=0+0 face=1
>
> This is a mode line, so it figures out: extend_face_to_end_of_line was
> called when the iterator was processing the final blanks of the mode
> line, see display_mode_line.