ref: bb4edc923597aa48da0d0ac217e7a80d41e77f0d
parent: 8c16ed361caf08cf4614378c3a0bf53a0b53ee4e
author: David Turner <[email protected]>
date: Sat Jan 21 09:31:45 EST 2006
* src/autofit/aflatin.c, src/autofit/afwarp.h, src/autofit/afwarp.c,
src/autofit/aftypes.h, src/autofit/afloader.c, src/autofit/autofit.c:
adding experimental implementation of "warp hinting" (new hinting
algorithm for gray-level and LCD rendering). It is disabled by default,
you need to #define AF_USE_WARPER in aftypes.h to enable it.
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2006-01-20 David Turner <[email protected]>
+
+ * src/autofit/aflatin.c, src/autofit/afwarp.h, src/autofit/afwarp.c,
+ src/autofit/aftypes.h, src/autofit/afloader.c, src/autofit/autofit.c:
+
+ adding experimental implementation of "warp hinting" (new hinting
+ algorithm for gray-level and LCD rendering). It is disabled by default,
+ you need to #define AF_USE_WARPER in aftypes.h to enable it.
+
2006-01-19 David Turner <[email protected]>
* src/sfnt/ttsbit0.c (tt_face_load_strike_metrics): fixed small
--- a/src/autofit/Jamfile
+++ b/src/autofit/Jamfile
@@ -16,7 +16,7 @@
if $(FT2_MULTI)
{- _sources = afangles afglobal afhints aflatin afloader afmodule afdummy ;
+ _sources = afangles afglobal afhints aflatin afloader afmodule afdummy afwarp ;
}
else
{--- a/src/autofit/afhints.c
+++ b/src/autofit/afhints.c
@@ -1140,5 +1140,28 @@
}
}
+#ifdef AF_USE_WARPER
+ FT_LOCAL_DEF( void )
+ af_glyph_hints_scale_dim( AF_GlyphHints hints,
+ AF_Dimension dim,
+ FT_Fixed scale,
+ FT_Pos delta )
+ {+ AF_Point points = hints->points;
+ AF_Point points_limit = points + hints->num_points;
+ AF_Point point;
+
+ if ( dim == AF_DIMENSION_HORZ )
+ {+ for ( point = points; point < points_limit; point++ )
+ point->x = FT_MulFix( point->fx, scale ) + delta;
+ }
+ else
+ {+ for ( point = points; point < points_limit; point++ )
+ point->y = FT_MulFix( point->fy, scale ) + delta;
+ }
+ }
+#endif /* AF_USE_WARPER */
/* END */
--- a/src/autofit/afhints.h
+++ b/src/autofit/afhints.h
@@ -272,6 +272,14 @@
af_glyph_hints_align_weak_points( AF_GlyphHints hints,
AF_Dimension dim );
+#ifdef AF_USE_WARPER
+ FT_LOCAL( void )
+ af_glyph_hints_scale_dim( AF_GlyphHints hints,
+ AF_Dimension dim,
+ FT_Fixed scale,
+ FT_Pos delta );
+#endif
+
FT_LOCAL( void )
af_glyph_hints_done( AF_GlyphHints hints );
--- a/src/autofit/aflatin.c
+++ b/src/autofit/aflatin.c
@@ -20,6 +20,10 @@
#include "aferrors.h"
+#ifdef AF_USE_WARPER
+#include "afwarp.h"
+#endif
+
/*************************************************************************/
/*************************************************************************/
/***** *****/
@@ -1311,6 +1315,13 @@
/* compute flags depending on render mode, etc. */
mode = metrics->root.scaler.render_mode;
+#ifdef AF_USE_WARPER
+ if ( mode == FT_RENDER_MODE_LCD || mode == FT_RENDER_MODE_LCD_V )
+ {+ metrics->root.scaler.render_mode = mode = FT_RENDER_MODE_NORMAL;
+ }
+#endif
+
scaler_flags = hints->scaler_flags;
other_flags = 0;
@@ -1940,6 +1951,19 @@
if ( ( dim == AF_DIMENSION_HORZ && AF_HINTS_DO_HORIZONTAL( hints ) ) ||
( dim == AF_DIMENSION_VERT && AF_HINTS_DO_VERTICAL( hints ) ) )
{+#ifdef AF_USE_WARPER
+ if ( dim == AF_DIMENSION_HORZ &&
+ metrics->root.scaler.render_mode == FT_RENDER_MODE_NORMAL )
+ {+ AF_WarperRec warper;
+ FT_Fixed scale;
+ FT_Pos delta;
+
+ af_warper_compute( &warper, hints, dim, &scale, &delta );
+ af_glyph_hints_scale_dim( hints, dim, scale, delta );
+ continue;
+ }
+#endif
af_latin_hint_edges( hints, (AF_Dimension)dim );
af_glyph_hints_align_edge_points( hints, (AF_Dimension)dim );
af_glyph_hints_align_strong_points( hints, (AF_Dimension)dim );
--- a/src/autofit/afloader.c
+++ b/src/autofit/afloader.c
@@ -191,7 +191,7 @@
AF_Edge edge2 = edge1 +
axis->num_edges - 1; /* rightmost edge */
-
+#ifndef AF_USE_WARPER
if ( axis->num_edges > 1 )
{old_advance = loader->pp2.x;
@@ -228,6 +228,7 @@
}
else
+#endif /* !AF_USE_WARPER */
{loader->pp1.x = FT_PIX_ROUND( loader->pp1.x );
loader->pp2.x = FT_PIX_ROUND( loader->pp2.x );
--- a/src/autofit/aftypes.h
+++ b/src/autofit/aftypes.h
@@ -53,6 +53,7 @@
/*************************************************************************/
/*************************************************************************/
+#define xxAF_USE_WARPER /* only define to use warp hinting */
#define xxAF_DEBUG
#ifdef AF_DEBUG
--- /dev/null
+++ b/src/autofit/afwarp.c
@@ -1,0 +1,270 @@
+#include "afwarp.h"
+
+#if 1
+static const AF_WarpScore
+af_warper_weights[ 64 ] =
+{+ 35, 20, 20, 20, 15, 12, 10, 5, 2, 1, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, -1, -2, -5, -8,-10,-10,-20,-20,-30,-30,
+
+ -30,-30,-20,-20,-10,-10, -8, -5, -2, -1, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 1, 2, 5, 10, 12, 15, 20, 20, 20,
+};
+#else
+static const AF_WarpScore
+af_warper_weights[ 64 ] =
+{+ 30, 20, 10, 5, 4, 4, 3, 2, 1, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, -1, -2, -2, -5, -5,-10,-10,-15,-20,
+
+ -20,-15,-15,-10,-10, -5, -5, -2, -2, -1, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 4, 5, 10, 20,
+};
+#endif
+
+static void
+af_warper_compute_line_best( AF_Warper warper,
+ FT_Fixed scale,
+ FT_Pos delta,
+ FT_Pos xx1,
+ FT_Pos xx2,
+ AF_WarpScore base_distort,
+ AF_Segment segments,
+ FT_UInt num_segments )
+{+ FT_Int idx_min, idx_max, idx0, xx1min, xx1max;
+ FT_UInt nn;
+ AF_WarpScore scores[64];
+
+ for ( nn = 0; nn < 64; nn++ )
+ scores[nn] = 0;
+
+ idx0 = xx1 - warper->t1;
+
+ /* compute minimum and maximum indices */
+ {+ FT_Pos xx1min = warper->x1min;
+ FT_Pos xx1max = warper->x1max;
+ FT_Pos w = xx2 - xx1;
+
+ if ( xx1min + w < warper->x2min )
+ xx1min = warper->x2min - (xx2-xx1);
+
+ xx1max = warper->x1max;
+ if ( xx1max + w > warper->x2max )
+ xx1max = warper->x2max - (xx2-xx1);
+
+ idx_min = xx1min - warper->t1;
+ idx_max = xx1max - warper->t1;
+
+ if ( idx_min > idx_max )
+ {+ printf( "invalid indices min=%d max=%d xx1=%d xx2=%d x1min=%d x1max=%d x2min=%d x2max=%d\n",
+ idx_min, idx_max, xx1, xx2, warper->x1min, warper->x1max, warper->x2min, warper->x2max );
+ return;
+ }
+ }
+
+ for ( nn = 0; nn < num_segments; nn++ )
+ {+ FT_Pos len = segments[nn].max_coord - segments[nn].min_coord;
+ FT_Pos y0 = FT_MulFix( segments[nn].pos, scale ) + delta;
+ FT_Pos y = y0 + (idx_min - idx0);
+ FT_Int idx;
+
+ for ( idx = idx_min; idx <= idx_max; idx++, y++ )
+ scores[idx] += af_warper_weights[ y & 63 ]*len;
+ }
+
+ /* find best score */
+ {+ FT_Int idx;
+
+ for ( idx = idx_min; idx <= idx_max; idx++ )
+ {+ AF_WarpScore score = scores[idx];
+ AF_WarpScore distort = base_distort + (idx - idx0);
+
+ if ( score > warper->best_score ||
+ ( score == warper->best_score &&
+ distort < warper->best_distort ) )
+ {+ warper->best_score = score;
+ warper->best_distort = distort;
+ warper->best_scale = scale;
+ warper->best_delta = delta + (idx-idx0);
+ }
+ }
+ }
+}
+
+
+FT_LOCAL_DEF( void )
+af_warper_compute( AF_Warper warper,
+ AF_GlyphHints hints,
+ AF_Dimension dim,
+ FT_Fixed *a_scale,
+ FT_Pos *a_delta )
+{+ AF_AxisHints axis;
+ AF_Point points;
+ FT_Fixed org_scale;
+ FT_Pos org_delta;
+ FT_UInt nn, num_points, num_segments;
+ FT_Int X1, X2;
+ FT_Int w;
+ AF_WarpScore base_distort;
+ AF_Segment segments;
+
+ /* get original scaling transform */
+ if ( dim == AF_DIMENSION_VERT )
+ {+ org_scale = hints->y_scale;
+ org_delta = hints->y_delta;
+ }
+ else
+ {+ org_scale = hints->x_scale;
+ org_delta = hints->x_delta;
+ }
+
+ warper->best_scale = org_scale;
+ warper->best_delta = org_delta;
+ warper->best_score = 0;
+ warper->best_distort = 0;
+
+ axis = &hints->axis[dim];
+ segments = axis->segments;
+ num_segments = axis->num_segments;
+ points = hints->points;
+ num_points = hints->num_points;
+
+ *a_scale = org_scale;
+ *a_delta = org_delta;
+
+ /* get X1 and X2, minimum and maximum in original coordinates */
+ if ( axis->num_segments < 1 )
+ return;
+
+#if 1
+ X1 = X2 = points[0].fx;
+ for ( nn = 1; nn < num_points; nn++ )
+ {+ FT_Int X = points[nn].fx;
+
+ if ( X < X1 )
+ X1 = X;
+ if ( X > X2 )
+ X2 = X;
+ }
+#else
+ X1 = X2 = segments[0].pos;
+ for ( nn = 1; nn < num_segments; nn++ )
+ {+ FT_Int X = segments[nn].pos;
+
+ if ( X < X1 )
+ X1 = X;
+ if ( X > X2 )
+ X2 = X;
+ }
+#endif
+
+ if ( X1 >= X2 )
+ return;
+
+ warper->x1 = FT_MulFix( X1, org_scale ) + org_delta;
+ warper->x2 = FT_MulFix( X2, org_scale ) + org_delta;
+
+ warper->t1 = AF_WARPER_FLOOR(warper->x1);
+ warper->t2 = AF_WARPER_CEIL(warper->x2);
+
+ warper->x1min = warper->x1 & ~31;
+ warper->x1max = warper->x1min + 32;
+ warper->x2min = warper->x2 & ~31;
+ warper->x2max = warper->x2min + 32;
+
+ if ( warper->x1max > warper->x2 )
+ warper->x1max = warper->x2;
+
+ if ( warper->x2min < warper->x1 )
+ warper->x2min = warper->x1;
+
+ warper->w0 = warper->x2 - warper->x1;
+
+ if ( warper->w0 <= 64 )
+ {+ warper->x1max = warper->x1;
+ warper->x2min = warper->x2;
+ }
+
+ warper->wmin = warper->x2min - warper->x1max;
+ warper->wmax = warper->x2max - warper->x1min;
+
+ if ( warper->wmin < warper->w0 - 32 )
+ warper->wmin = warper->w0 - 32;
+
+ if ( warper->wmax > warper->w0 + 32 )
+ warper->wmax = warper->w0 + 32;
+
+ if ( warper->wmin < warper->w0*3/4 )
+ warper->wmin = warper->w0*3/4;
+
+ if ( warper->wmax > warper->w0*5/4 )
+ warper->wmax = warper->w0*5/4;
+
+
+ /* warper->wmin = warper->wmax = warper->w0; */
+
+ for ( w = warper->wmin; w <= warper->wmax; w++ )
+ {+ FT_Int line = w - warper->wmin;
+ FT_Fixed new_scale;
+ FT_Pos new_delta;
+ FT_Pos xx1, xx2;
+
+ xx1 = warper->x1;
+ xx2 = warper->x2;
+ if ( w >= warper->w0 )
+ {+ xx1 -= (w-warper->w0);
+ if ( xx1 < warper->x1min )
+ {+ xx2 += warper->x1min - xx1;
+ xx1 = warper->x1min;
+ }
+ }
+ else
+ {+ xx1 -= (w-warper->w0);
+ if ( xx1 > warper->x1max )
+ {+ xx2 -= (xx1-warper->x1max);
+ xx1 = warper->x1max;
+ }
+ }
+
+ if ( xx1 < warper->x1 )
+ base_distort = warper->x1 - xx1;
+ else
+ base_distort = xx1 - warper->x1;
+
+ if ( xx2 < warper->x2 )
+ base_distort += warper->x2 - xx2;
+ else
+ base_distort += xx2 - warper->x2;
+
+ base_distort *= 10;
+
+ new_scale = org_scale + FT_DivFix( w - warper->w0, X2-X1 );
+ new_delta = xx1 - FT_MulFix( X1, new_scale );
+
+ af_warper_compute_line_best( warper, new_scale, new_delta, xx1, xx2,
+ base_distort,
+ segments, num_segments );
+ }
+
+ *a_scale = warper->best_scale;
+ *a_delta = warper->best_delta;
+}
+
--- /dev/null
+++ b/src/autofit/afwarp.h
@@ -1,0 +1,40 @@
+#ifndef __AFWARP_H__
+#define __AFWARP_H__
+
+#include "afhints.h"
+
+FT_BEGIN_HEADER
+
+#define AF_WARPER_SCALE
+
+#define AF_WARPER_FLOOR(x) ((x) & ~63)
+#define AF_WARPER_CEIL(x) AF_WARPER_FLOOR((x)+63)
+
+typedef FT_Int32 AF_WarpScore;
+
+typedef struct
+{+ FT_Int X1, X2;
+ FT_Pos x1, x2;
+ FT_Pos t1, t2;
+ FT_Pos x1min, x1max;
+ FT_Pos x2min, x2max;
+ FT_Pos w0, wmin, wmax;
+
+ FT_Fixed best_scale;
+ FT_Pos best_delta;
+ AF_WarpScore best_score;
+ AF_WarpScore best_distort;
+
+} AF_WarperRec, *AF_Warper;
+
+FT_LOCAL( void )
+af_warper_compute( AF_Warper warper,
+ AF_GlyphHints hints,
+ AF_Dimension dim,
+ FT_Fixed *a_scale,
+ FT_Fixed *a_delta );
+
+FT_END_HEADER
+
+#endif /* __AFWARP_H__ */
--- a/src/autofit/autofit.c
+++ b/src/autofit/autofit.c
@@ -26,5 +26,8 @@
#include "afloader.c"
#include "afmodule.c"
+#ifdef AF_USE_WARPER
+#include "afwarp.c"
+#endif
/* END */