small fix to the auto-hinter:

the filling direction of each glyph is now re-computed on the
fly, given that we cannot rely on the "flags" field of the
source outline..

this fixes problems with many fonts, including the Arphic ones
(not to say that CJK fonts are handled better for now though..)
This commit is contained in:
David Turner 2000-07-27 15:59:08 +00:00
parent 6ac722b229
commit 666b11d59c
1 changed files with 145 additions and 1 deletions

View File

@ -68,6 +68,134 @@
}
/* this function is used by ah_get_orientation (see below) to test */
/* the fill direction of a given bbox extrema.. */
static
int ah_test_extrema( FT_Outline* outline,
int n )
{
FT_Vector *prev, *cur, *next;
FT_Pos product;
FT_Int first, last, c;
/* we need to compute the `previous' and `next' point */
/* for these extrema. */
cur = outline->points + n;
prev = cur - 1;
next = cur + 1;
first = 0;
for ( c = 0; c < outline->n_contours; c++ )
{
last = outline->contours[c];
if ( n == first )
prev = outline->points + last;
if ( n == last )
next = outline->points + first;
first = last + 1;
}
product = FT_MulDiv( cur->x - prev->x, /* in.x */
next->y - cur->y, /* out.y */
0x40 )
-
FT_MulDiv( cur->y - prev->y, /* in.y */
next->x - cur->x, /* out.x */
0x40 );
if ( product )
product = product > 0 ? 2 : 1;
return product;
}
/* Compute the orientation of path filling. It differs between TrueType */
/* and Type1 formats. We could use the `ft_outline_reverse_fill' flag, */
/* but it is better to re-compute it directly (it seems that this flag */
/* isn't correctly set for some weird composite glyphs currently). */
/* */
/* We do this by computing bounding box points, and computing their */
/* curvature. */
/* */
/* The function returns either 1 or -1. */
/* */
static
int ah_get_orientation( FT_Outline* outline )
{
FT_BBox box;
FT_BBox indices;
int n, last;
indices.xMin = -1;
indices.yMin = -1;
indices.xMax = -1;
indices.yMax = -1;
box.xMin = box.yMin = 32767;
box.xMax = box.yMax = -32768;
/* is it empty ? */
if ( outline->n_contours < 1 )
return 1;
last = outline->contours[outline->n_contours - 1];
for ( n = 0; n <= last; n++ )
{
FT_Pos x, y;
x = outline->points[n].x;
if ( x < box.xMin )
{
box.xMin = x;
indices.xMin = n;
}
if ( x > box.xMax )
{
box.xMax = x;
indices.xMax = n;
}
y = outline->points[n].y;
if ( y < box.yMin )
{
box.yMin = y;
indices.yMin = n;
}
if ( y > box.yMax )
{
box.yMax = y;
indices.yMax = n;
}
}
/* test orientation of the xmin */
n = ah_test_extrema( outline, indices.xMin );
if (n) goto Exit;
n = ah_test_extrema( outline, indices.yMin );
if (n) goto Exit;
n = ah_test_extrema( outline, indices.xMax );
if (n) goto Exit;
n = ah_test_extrema( outline, indices.yMax );
if (!n)
n = 1;
Exit:
return n;
}
/*************************************************************************/
/* */
/* <Function> */
@ -218,6 +346,20 @@
outline->num_hsegments = 0;
outline->num_vsegments = 0;
#if 1
/* we can't rely on the value of FT_Outline.flags to know the */
/* fill direction used for a glyph, given that some fonts are */
/* broken (e.g. the Arphic ones..). We thus recompute it each */
/* time we need to.. */
outline->vert_major_dir = ah_dir_up;
outline->horz_major_dir = ah_dir_left;
if ( ah_get_orientation( source ) > 1 )
{
outline->vert_major_dir = ah_dir_down;
outline->horz_major_dir = ah_dir_right;
}
#else
/* Compute the vertical and horizontal major directions; this is */
/* currently done by inspecting the `ft_outline_reverse_fill' flag. */
/* However, some fonts have improper glyphs, and it'd be a good idea */
@ -230,11 +372,13 @@
outline->vert_major_dir = ah_dir_down;
outline->horz_major_dir = ah_dir_right;
}
#endif
outline->x_scale = face->size->metrics.x_scale;
outline->y_scale = face->size->metrics.y_scale;
points = outline->points;
if (outline->num_points == 0)
goto Exit;
{
/* do one thing at a time -- it is easier to understand, and */