ref: a0172d10e816fdd7b8d7b748f570ba16d9e753bd
parent: 815c32469b378737e9f36da327a181586bd48e18
author: Alexei Podtelezhnikov <[email protected]>
date: Mon Aug 17 18:58:59 EDT 2015
[base] Improve emboldener (#45596). * src/base/ftoutln.c (FT_Outline_EmboldenXY): Correct displacement of zero-lenght segments.
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2015-08-17 Alexei Podtelezhnikov <[email protected]>
+
+ [base] Improve emboldener (#45596).
+
+ * src/base/ftoutln.c (FT_Outline_EmboldenXY): Correct displacement
+ of zero-lenght segments.
+
2015-08-16 Alexei Podtelezhnikov <[email protected]>
[base] Reoptimize arithmetic.
--- a/src/base/ftoutln.c
+++ b/src/base/ftoutln.c
@@ -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];
+ if ( j != k )
+ {+ out.x = points[j].x - points[i].x;
+ out.y = points[j].y - points[i].y;
+ l_out = FT_Vector_NormLen( &out );
+ }
else
- v_next = v_first;
+ {+ out = anchor;
+ l_out = l_anchor;
+ }
- /* 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 );
+ if ( l_out == 0 )
+ continue;
- 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 ( l_in != 0 )
{- d = d + 0x10000L;
+ if ( k < 0 )
+ {+ k = i;
+ anchor = in;
+ l_anchor = l_in;
+ }
- /* shift along lateral bisector in appropriate orientation */
- shift.x = in.y + out.y;
- shift.y = in.x + out.x;
+ d = FT_MulFix( in.x, out.x ) + FT_MulFix( in.y, out.y );
- if ( orientation == FT_ORIENTATION_TRUETYPE )
- shift.x = -shift.x;
- else
- shift.y = -shift.y;
+ /* shift only if turn is less than ~160 degrees */
+ if ( d > -0xF000L )
+ {+ d = d + 0x10000L;
- /* 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;
+ /* shift components along lateral bisector in proper orientation */
+ shift.x = in.y + out.y;
+ shift.y = in.x + out.x;
- l = FT_MIN( l_in, l_out );
+ if ( orientation == FT_ORIENTATION_TRUETYPE )
+ shift.x = -shift.x;
+ else
+ shift.y = -shift.y;
- /* 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 );
+ /* 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 );
- if ( FT_MulFix( ystrength, q ) <= FT_MulFix( l, d ) )
- shift.y = FT_MulDiv( shift.y, ystrength, d );
+ /* 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.y = FT_MulDiv( shift.y, l, q );
+ 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
- shift.x = shift.y = 0;
+ i = j;
- points[n].x = v_cur.x + xstrength + shift.x;
- points[n].y = v_cur.y + ystrength + shift.y;
-
- in = out;
- l_in = l_out;
- v_cur = v_next;
+ in = out;
+ l_in = l_out;
}
first = last + 1;