minhngoc25a
/
freetype2
mirror of git://git.savannah.gnu.org/freetype/freetype2.git
2
1
Fork 2
Code Issues 9 Releases Wiki Activity

[base] Improve emboldener (#45596). 

* src/base/ftoutln.c (FT_Outline_EmboldenXY): Correct displacement
of zero-lenght segments.
This commit is contained in:
Alexei Podtelezhnikov 2015-08-17 22:58:59 -04:00
parent 815c32469b
commit a0172d10e8
2 changed files with 87 additions and 63 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
ChangeLog
View File

@ -1,3 +1,10 @@
2015-08-17 Alexei Podtelezhnikov <apodtele@gmail.com>
[base] Improve emboldener (#45596).
* src/base/ftoutln.c (FT_Outline_EmboldenXY): Correct displacement
of zero-lenght segments.
2015-08-16 Alexei Podtelezhnikov <apodtele@gmail.com>
[base] Reoptimize arithmetic.

143
src/base/ftoutln.c
View File

@ -908,8 +908,7 @@
FT_Pos ystrength )
{
FT_Vector* points;
FT_Vector v_prev, v_first, v_next, v_cur;
FT_Int c, n, first;
FT_Int c, first, last;
FT_Int orientation;
@ -935,76 +934,94 @@
first = 0;
for ( c = 0; c < outline->n_contours; c++ )
{
FT_Vector in, out, shift;
FT_Fixed l_in, l_out, l, q, d;
FT_Int last = outline->contours[c];
FT_Vector in, out, anchor, shift;
FT_Fixed l_in = 0, l_out, l_anchor, l, q, d;
FT_Int i, j, k;
v_first = points[first];
v_prev = points[last];
v_cur = v_first;
last = outline->contours[c];
/* compute incoming normalized vector */
in.x = v_cur.x - v_prev.x;
in.y = v_cur.y - v_prev.y;
l_in = (FT_Fixed)FT_Vector_NormLen( &in );
for ( n = first; n <= last; n++ )
/* Counter i cycles though the points; counter j advances only */
/* when points are moved; anchor k markes the first moved point. */
for ( i = last, j = first, k = -1;
j != i && i != k;
j = j < last ? j + 1 : first )
{
if ( n < last )
v_next = points[n + 1];
else
v_next = v_first;
/* compute outgoing normalized vector */
out.x = v_next.x - v_cur.x;
out.y = v_next.y - v_cur.y;
l_out = (FT_Fixed)FT_Vector_NormLen( &out );
d = FT_MulFix( in.x, out.x ) + FT_MulFix( in.y, out.y );
/* shift only if turn is less than ~160 degrees */
if ( d > -0xF000L )
if ( j != k )
{
d = d + 0x10000L;
/* shift along lateral bisector in appropriate orientation */
shift.x = in.y + out.y;
shift.y = in.x + out.x;
if ( orientation == FT_ORIENTATION_TRUETYPE )
shift.x = -shift.x;
else
shift.y = -shift.y;
/* restrict shift magnitude to better handle collapsing segments */
q = FT_MulFix( out.x, in.y ) - FT_MulFix( out.y, in.x );
if ( orientation == FT_ORIENTATION_TRUETYPE )
q = -q;
l = FT_MIN( l_in, l_out );
/* non-strict inequalities avoid divide-by-zero when q == l == 0 */
if ( FT_MulFix( xstrength, q ) <= FT_MulFix( l, d ) )
shift.x = FT_MulDiv( shift.x, xstrength, d );
else
shift.x = FT_MulDiv( shift.x, l, q );
if ( FT_MulFix( ystrength, q ) <= FT_MulFix( l, d ) )
shift.y = FT_MulDiv( shift.y, ystrength, d );
else
shift.y = FT_MulDiv( shift.y, l, q );
out.x = points[j].x - points[i].x;
out.y = points[j].y - points[i].y;
l_out = FT_Vector_NormLen( &out );
}
else
shift.x = shift.y = 0;
{
out = anchor;
l_out = l_anchor;
}
points[n].x = v_cur.x + xstrength + shift.x;
points[n].y = v_cur.y + ystrength + shift.y;
if ( l_out == 0 )
continue;
in = out;
l_in = l_out;
v_cur = v_next;
if ( l_in != 0 )
{
if ( k < 0 )
{
k = i;
anchor = in;
l_anchor = l_in;
}
d = FT_MulFix( in.x, out.x ) + FT_MulFix( in.y, out.y );
/* shift only if turn is less than ~160 degrees */
if ( d > -0xF000L )
{
d = d + 0x10000L;
/* shift components along lateral bisector in proper orientation */
shift.x = in.y + out.y;
shift.y = in.x + out.x;
if ( orientation == FT_ORIENTATION_TRUETYPE )
shift.x = -shift.x;
else
shift.y = -shift.y;
/* restrict shift magnitude to better handle collapsing segments */
q = FT_MulFix( out.x, in.y ) - FT_MulFix( out.y, in.x );
if ( orientation == FT_ORIENTATION_TRUETYPE )
q = -q;
l = FT_MIN( l_in, l_out );
/* non-strict inequalities avoid divide-by-zero when q == l == 0 */
if ( FT_MulFix( xstrength, q ) <= FT_MulFix( l, d ) )
shift.x = FT_MulDiv( shift.x, xstrength, d );
else
shift.x = FT_MulDiv( shift.x, l, q );
if ( FT_MulFix( ystrength, q ) <= FT_MulFix( l, d ) )
shift.y = FT_MulDiv( shift.y, ystrength, d );
else
shift.y = FT_MulDiv( shift.y, l, q );
}
else
shift.x = shift.y = 0;
for ( ;
i != j;
i = i < last ? i + 1 : first )
{
points[i].x += xstrength + shift.x;
points[i].y += ystrength + shift.y;
}
}
else
i = j;
in = out;
l_in = l_out;
}
first = last + 1;