ref: a186139cad1a793038d83a25c08b32089dabb227
parent: 29873a0ccd69376125323ded561e271872564077
author: David Turner <[email protected]>
date: Mon Oct 23 12:00:59 EDT 2006
improve FT_Outline_Get_Orientation for broken asian fonts
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2006-10-23 Zhe Su <[email protected]>
+
+ * src/base/ftoutln.c: re-implementing FT_Outline_Get_Orientation to
+ better deal with broken Asian fonts with funky glyphs with
+ self-intersections and other stupid things
+
2006-10-23 David Turner <[email protected]>
* src/sfnt/ttmtx.c, src/cff/cffload.c: speeding up the CFF font
--- a/src/base/ftoutln.c
+++ b/src/base/ftoutln.c
@@ -934,7 +934,8 @@
FT_Outline_Get_Orientation( FT_Outline* outline )
{FT_Pos xmin = 32768L;
- FT_Vector* xmin_point = NULL;
+ FT_Pos xmin_ymin = 32768L;
+ FT_Pos xmin_ymax = -32768L;
FT_Vector* xmin_first = NULL;
FT_Vector* xmin_last = NULL;
@@ -943,8 +944,11 @@
FT_Vector* first;
FT_Vector* last;
FT_Vector* prev;
- FT_Vector* next;
+ FT_Vector* point;
+ int i;
+ FT_Pos ray_y [3];
+ int result [3];
if ( !outline || outline->n_points <= 0 )
return FT_ORIENTATION_TRUETYPE;
@@ -954,11 +958,10 @@
contour < outline->contours + outline->n_contours;
contour++, first = last + 1 )
{- FT_Vector* point;
- FT_Int on_curve;
- FT_Int on_curve_count = 0;
- FT_Pos tmp_xmin = 32768L;
- FT_Vector* tmp_xmin_point = NULL;
+ FT_Pos contour_xmin = 32768L;
+ FT_Pos contour_xmax = -32768L;
+ FT_Pos contour_ymin = 32768L;
+ FT_Pos contour_ymax = -32768L;
last = outline->points + *contour;
@@ -968,74 +971,106 @@
for ( point = first; point <= last; ++point )
{- /* Count on-curve points. If there are less than 3 on-curve */
- /* points, just bypass this contour. */
- on_curve = outline->tags[point - outline->points] & 1;
- on_curve_count += on_curve;
+ if ( point->x < contour_xmin )
+ contour_xmin = point->x;
- if ( point->x < tmp_xmin && on_curve )
- {- tmp_xmin = point->x;
- tmp_xmin_point = point;
- }
+ if ( point->x > contour_xmax )
+ contour_xmax = point->x;
+
+ if ( point->y < contour_ymin )
+ contour_ymin = point->y;
+
+ if ( point->y > contour_ymax )
+ contour_ymax = point->y;
}
- if ( on_curve_count > 2 && tmp_xmin < xmin )
+ if ( contour_xmin < xmin &&
+ contour_xmin != contour_xmax &&
+ contour_ymin != contour_ymax )
{- xmin = tmp_xmin;
- xmin_point = tmp_xmin_point;
+ xmin = contour_xmin;
+ xmin_ymin = contour_ymin;
+ xmin_ymax = contour_ymax;
xmin_first = first;
xmin_last = last;
}
}
- if ( !xmin_point )
+ if ( xmin == 32768 )
return FT_ORIENTATION_TRUETYPE;
- prev = ( xmin_point == xmin_first ) ? xmin_last : xmin_point - 1;
- next = ( xmin_point == xmin_last ) ? xmin_first : xmin_point + 1;
+ ray_y[0] = (xmin_ymin*3 + xmin_ymax) >> 2;
+ ray_y[1] = (xmin_ymin + xmin_ymax) >> 1;
+ ray_y[2] = (xmin_ymin + xmin_ymax*3) >> 2;
- /* Skip off-curve points */
- while ( ( outline->tags[prev - outline->points] & 1 ) == 0 )
+ for ( i = 0; i < 3; i++ )
{- if ( prev == xmin_first )
- prev = xmin_last;
- else
- --prev;
- }
+ FT_Pos left_x;
+ FT_Pos right_x;
+ FT_Vector* left1;
+ FT_Vector* left2;
+ FT_Vector* right1;
+ FT_Vector* right2;
- while ( ( outline->tags[next - outline->points] & 1 ) == 0 )
- {- if ( next == xmin_last )
- next = xmin_first;
- else
- ++next;
- }
+ RedoRay:
+ left_x = 32768L;
+ right_x = -32768L;
-#if 1
+ left1 = left2 = right1 = right2 = NULL;
- {- FT_Pos dx1 = prev->x - xmin_point->x;
- FT_Pos dy1 = prev->y - xmin_point->y;
- FT_Pos dx2 = next->x - xmin_point->x;
- FT_Pos dy2 = next->y - xmin_point->y;
+ prev = xmin_last;
+ for ( point = xmin_first; point <= xmin_last; prev = point, ++point )
+ {+ FT_Pos tmp_x;
+ if ( point->y == ray_y[i] || prev->y == ray_y[i] )
+ {+ ++ ray_y[i];
+ goto RedoRay;
+ }
- if ( dy1 * dx2 > dy2 * dx1 )
- return FT_ORIENTATION_POSTSCRIPT;
- else
- return FT_ORIENTATION_TRUETYPE;
+ if ( (point->y < ray_y[i] && prev->y < ray_y[i]) ||
+ (point->y > ray_y[i] && prev->y > ray_y[i]) )
+ {+ continue;
+ }
+
+ tmp_x = FT_MulDiv( point->x - prev->x, ray_y[i] - prev->y, point->y - prev->y ) + prev->x;
+
+ if ( tmp_x < left_x )
+ {+ left_x = tmp_x;
+ left1 = prev;
+ left2 = point;
+ }
+
+ if ( tmp_x > right_x )
+ {+ right_x = tmp_x;
+ right1 = prev;
+ right2 = point;
+ }
+ }
+
+ if ( left1 && right1 )
+ {+ if ( left1->y < left2->y && right1->y > right2->y )
+ result[i] = FT_ORIENTATION_TRUETYPE;
+ else if ( left1->y > left2->y && right1->y < right2->y )
+ result[i] = FT_ORIENTATION_POSTSCRIPT;
+ else
+ result[i] = FT_ORIENTATION_NONE;
+ }
}
-#else /* 0 */
+ if ( result[0] != FT_ORIENTATION_NONE &&
+ (result[0] == result[1] || result[0] == result[2]) )
+ return result[0];
- if ( FT_Atan2( prev->x - xmin_point->x, prev->y - xmin_point->y ) >
- FT_Atan2( next->x - xmin_point->x, next->y - xmin_point->y ) )
- return FT_ORIENTATION_POSTSCRIPT;
- else
- return FT_ORIENTATION_TRUETYPE;
+ if ( result[1] != FT_ORIENTATION_NONE && result[1] == result[2] )
+ return result[1];
-#endif /* 0 */
+ return FT_ORIENTATION_TRUETYPE;
}