ref: f3823281311eefb3b109289796cefee8ce9fac61
parent: 4d3e56392fd0a89d97cb3f567d713cb15ac74cbf
author: David Turner <[email protected]>
date: Fri May 5 09:11:36 EDT 2000
added experimental emboldening/outlining code. This is incomplete and will not compile so turned off
--- a/src/base/ftglyph.c
+++ b/src/base/ftglyph.c
@@ -498,3 +498,305 @@
;
}
}
+
+
+ /***************************************************************************/
+ /***************************************************************************/
+ /**** ****/
+ /**** EXPERIMENTAL EMBOLDENING/OUTLINING SUPPORT ****/
+ /**** ****/
+ /***************************************************************************/
+ /***************************************************************************/
+
+#if 0
+
+/* Compute the norm of a vector */
+#ifdef FT_CONFIG_OPTION_OLD_CALCS
+ static
+ FT_Pos ft_norm( FT_Vector* vec )
+ {+ FT_Int64 t1, t2;
+
+ MUL_64( vec->x, vec->x, t1 );
+ MUL_64( vec->y, vec->y, t2 );
+ ADD_64( t1, t2, t1 );
+ return (FT_Pos)SQRT_64(t1);
+ }
+#else
+ static
+ FT_Pos ft_norm( FT_Vector* vec )
+ {+ FT_F26Dot6 u, v, d;
+ FT_Int shift;
+ FT_ULong H, L, L2, hi, lo, med;
+
+ u = vec->x; if (u < 0) u = -u;
+ v = vec->y; if (v < 0) v = -v;
+
+ if (u < v)
+ {+ d = u;
+ u = v;
+ v = d;
+ }
+
+ /* check that we're not trying to normalise zero !! */
+ if (u==0) return 0;
+
+ /* compute (u*u+v*v) on 64 bits with two 32-bit registers [H:L] */
+ hi = (FT_ULong)u >> 16;
+ lo = (FT_ULong)u & 0xFFFF;
+ med = hi*lo;
+
+ H = hi*hi + (med >> 15);
+ med <<= 17;
+ L = lo*lo + med;
+ if (L < med) H++;
+
+ hi = (FT_ULong)v >> 16;
+ lo = (FT_ULong)v & 0xFFFF;
+ med = hi*lo;
+
+ H += hi*hi + (med >> 15);
+ med <<= 17;
+ L2 = lo*lo + med;
+ if (L2 < med) H++;
+
+ L += L2;
+ if (L < L2) H++;
+
+ /* if the value is smaller than 32-bits */
+ shift = 0;
+ if (H == 0)
+ {+ while ((L & 0xC0000000) == 0)
+ {+ L <<= 2;
+ shift++;
+ }
+ return (FT_Sqrt32(L) >> shift);
+ }
+ else
+ {+ while (H)
+ {+ L = (L >> 2) | (H << 30);
+ H >>= 2;
+ shift++;
+ }
+ return (FT_Sqrt32(L) << shift);
+ }
+ }
+#endif
+
+ static
+ int ft_test_extrema( FT_Outline* outline,
+ int n )
+ {+ FT_Vector *prev, *cur, *next;
+ FT_Pos product;
+ FT_Int first, last;
+
+ /* we need to compute the "previous" and "next" point */
+ /* for this 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 ? 1 : -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's better to re-compute it directly (it seems that this flag */
+/* isn't correctly set for some weird composite glyphs for now).. */
+/* */
+/* We do this by computing bounding box points, and computing their */
+/* curvature.. the function returns either 1 or -1 */
+/* */
+ static
+ int ft_get_orientation( FT_Outline* outline )
+ {+ FT_BBox box;
+ FT_BBox indexes;
+ int n, last;
+
+ indexes.xMin = -1;
+ indexes.yMin = -1;
+ indexes.xMax = -1;
+ indexes.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;
+ indexes.xMin = n;
+ }
+
+ if ( x > box.xMax )
+ {+ box.xMax = x;
+ indexes.xMax = n;
+ }
+
+ y = outline->points[n].y;
+ if ( y < box.yMin )
+ {+ box.yMin = y;
+ indexes.yMin = n;
+ }
+
+ if ( y > box.yMax )
+ {+ box.yMax = y;
+ indexes.yMax = n;
+ }
+ }
+
+ /* test orientation of the xmin */
+ return ft_test_extrema( outline, indexes.xMin ) ||
+ ft_test_extrema( outline, indexes.yMin ) ||
+ ft_test_extrema( outline, indexes.xMax ) ||
+ ft_test_extrema( outline, indexes.yMax ) ||
+ 1; /* this is an empty glyph ?? */
+ }
+
+
+ static
+ FT_Error ft_embolden( FT_Face original,
+ FT_Outline* outline,
+ FT_Pos* advance )
+ {+ FT_Vector u, v;
+ FT_Vector* points;
+ FT_Vector cur, prev, next;
+ FT_Pos distance;
+ int c, n, first, orientation;
+
+ (void)advance;
+
+ /* compute control distance */
+ distance = FT_MulFix( original->em_size/60,
+ original->size->metrics.y_scale );
+
+ orientation = ft_get_orientation( &original->glyph->outline );
+
+ points = original->glyph->outline.points;
+
+ first = 0;
+ for ( c = 0; c < outline->n_contours; c++ )
+ {+ int last = outline->contours[c];
+
+ prev = points[last];
+
+ for ( n = first; n <= last; n++ )
+ {+ FT_Pos norme, delta, d;
+ FT_Vector in, out;
+
+ cur = points[n];
+ if ( n < last ) next = points[n+1];
+ else next = points[first];
+
+ /* compute the in and out vectors */
+ in.x = cur.x - prev.x;
+ in.y = cur.y - prev.y;
+
+ out.x = next.x - cur.x;
+ out.y = next.y - cur.y;
+
+ /* compute U and V */
+ norme = ft_norm( &in );
+ u.x = orientation * FT_DivFix( in.y, norme );
+ u.y = orientation * - FT_DivFix( in.x, norme );
+
+ norme = ft_norm( &out );
+ v.x = orientation * FT_DivFix( out.y, norme );
+ v.y = orientation * - FT_DivFix( out.x, norme );
+
+ d = distance;
+
+ if ( (outline->flags[n] & FT_Curve_Tag_On) == 0 )
+ d *= 2;
+
+ /* Check discriminant for parallel vectors */
+ delta = FT_MulFix( u.x, v.y ) - FT_MulFix( u.y, v.x );
+ if ( delta > FT_BOLD_THRESHOLD || delta < - FT_BOLD_THRESHOLD )
+ {+ /* Move point - compute A and B */
+ FT_Pos x, y, A, B;
+
+ A = d + FT_MulFix( cur.x, u.x ) + FT_MulFix( cur.y, u.y );
+ B = d + FT_MulFix( cur.x, v.x ) + FT_MulFix( cur.y, v.y );
+
+ x = FT_MulFix( A, v.y ) - FT_MulFix( B, u.y );
+ y = FT_MulFix( B, u.x ) - FT_MulFix( A, v.x );
+
+ outline->points[n].x = distance + FT_DivFix( x, delta );
+ outline->points[n].y = distance + FT_DivFix( y, delta );
+ }
+ else
+ {+ /* Vectors are nearly parallel */
+ FT_Pos x, y;
+
+ x = distance + cur.x + FT_MulFix( d, u.x + v.x )/2;
+ y = distance + cur.y + FT_MulFix( d, u.y + v.y )/2;
+
+ outline->points[n].x = x;
+ outline->points[n].y = y;
+ }
+
+ prev = cur;
+ }
+
+ first = last+1;
+ }
+
+ if (advance)
+ *advance = (*advance + distance*4) & -64;
+
+ return 0;
+ }
+
+#endif /* 0 - EXPERIMENTAL STUFF !! */