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-rw-r--r--src/smooth/ftgrays.c100
1 files changed, 51 insertions, 49 deletions
diff --git a/src/smooth/ftgrays.c b/src/smooth/ftgrays.c
index e9a3ce7a7..803a19e41 100644
--- a/src/smooth/ftgrays.c
+++ b/src/smooth/ftgrays.c
@@ -4,7 +4,7 @@
/* */
/* A new `perfect' anti-aliasing renderer (body). */
/* */
-/* Copyright 2000-2017 by */
+/* Copyright 2000-2018 by */
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
/* */
/* This file is part of the FreeType project, and may only be used, */
@@ -141,6 +141,16 @@
#define FT_INT_MAX INT_MAX
#define FT_ULONG_MAX ULONG_MAX
+#define ADD_LONG( a, b ) \
+ (long)( (unsigned long)(a) + (unsigned long)(b) )
+#define SUB_LONG( a, b ) \
+ (long)( (unsigned long)(a) - (unsigned long)(b) )
+#define MUL_LONG( a, b ) \
+ (long)( (unsigned long)(a) * (unsigned long)(b) )
+#define NEG_LONG( a ) \
+ (long)( -(unsigned long)(a) )
+
+
#define ft_memset memset
#define ft_setjmp setjmp
@@ -264,6 +274,7 @@ typedef ptrdiff_t FT_PtrDist;
#include "ftgrays.h"
#include FT_INTERNAL_OBJECTS_H
#include FT_INTERNAL_DEBUG_H
+#include FT_INTERNAL_CALC_H
#include FT_OUTLINE_H
#include "ftsmerrs.h"
@@ -359,7 +370,7 @@ typedef ptrdiff_t FT_PtrDist;
/* optimize a division and modulo operation on the same parameters */
/* into a single call to `__aeabi_idivmod'. See */
/* */
- /* http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43721 */
+ /* https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43721 */
#undef FT_DIV_MOD
#define FT_DIV_MOD( type, dividend, divisor, quotient, remainder ) \
FT_BEGIN_STMNT \
@@ -393,7 +404,7 @@ typedef ptrdiff_t FT_PtrDist;
/* need to define them to "float" or "double" when experimenting with */
/* new algorithms */
- typedef long TPos; /* sub-pixel coordinate */
+ typedef long TPos; /* subpixel coordinate */
typedef int TCoord; /* integer scanline/pixel coordinate */
typedef int TArea; /* cell areas, coordinate products */
@@ -571,8 +582,8 @@ typedef ptrdiff_t FT_PtrDist;
if ( ex < ras.min_ex )
ex = ras.min_ex - 1;
- /* record the current one if it is valid */
- if ( !ras.invalid )
+ /* record the current one if it is valid and substantial */
+ if ( !ras.invalid && ( ras.area || ras.cover ) )
gray_record_cell( RAS_VAR );
ras.area = 0;
@@ -1135,7 +1146,7 @@ typedef ptrdiff_t FT_PtrDist;
/* s is L * the perpendicular distance from P1 to the line P0-P3. */
dx1 = arc[1].x - arc[0].x;
dy1 = arc[1].y - arc[0].y;
- s = FT_ABS( dy * dx1 - dx * dy1 );
+ s = FT_ABS( SUB_LONG( MUL_LONG( dy, dx1 ), MUL_LONG( dx, dy1 ) ) );
if ( s > s_limit )
goto Split;
@@ -1143,7 +1154,7 @@ typedef ptrdiff_t FT_PtrDist;
/* s is L * the perpendicular distance from P2 to the line P0-P3. */
dx2 = arc[2].x - arc[0].x;
dy2 = arc[2].y - arc[0].y;
- s = FT_ABS( dy * dx2 - dx * dy2 );
+ s = FT_ABS( SUB_LONG( MUL_LONG( dy, dx2 ), MUL_LONG( dx, dy2 ) ) );
if ( s > s_limit )
goto Split;
@@ -1289,8 +1300,6 @@ typedef ptrdiff_t FT_PtrDist;
int y;
- FT_TRACE7(( "gray_sweep: start\n" ));
-
for ( y = ras.min_ey; y < ras.max_ey; y++ )
{
PCell cell = ras.ycells[y - ras.min_ey];
@@ -1316,8 +1325,6 @@ typedef ptrdiff_t FT_PtrDist;
if ( cover != 0 )
gray_hline( RAS_VAR_ x, y, cover, ras.max_ex - x );
}
-
- FT_TRACE7(( "gray_sweep: end\n" ));
}
@@ -1711,8 +1718,11 @@ typedef ptrdiff_t FT_PtrDist;
if ( !ras.invalid )
gray_record_cell( RAS_VAR );
- FT_TRACE7(( "band [%d..%d]: %d cells\n",
- ras.min_ey, ras.max_ey, ras.num_cells ));
+ FT_TRACE7(( "band [%d..%d]: %d cell%s\n",
+ ras.min_ey,
+ ras.max_ey,
+ ras.num_cells,
+ ras.num_cells == 1 ? "" : "s" ));
}
else
{
@@ -1729,35 +1739,43 @@ typedef ptrdiff_t FT_PtrDist;
static int
gray_convert_glyph( RAS_ARG )
{
+ const TCoord yMin = ras.min_ey;
+ const TCoord yMax = ras.max_ey;
+ const TCoord xMin = ras.min_ex;
+ const TCoord xMax = ras.max_ex;
+
TCell buffer[FT_MAX_GRAY_POOL];
- TCoord band_size = FT_MAX_GRAY_POOL / 8;
- TCoord count = ras.max_ey - ras.min_ey;
- int num_bands;
- TCoord min, max, max_y;
+ size_t height = (size_t)( yMax - yMin );
+ size_t n = FT_MAX_GRAY_POOL / 8;
+ TCoord y;
TCoord bands[32]; /* enough to accommodate bisections */
TCoord* band;
/* set up vertical bands */
- if ( count > band_size )
+ if ( height > n )
{
/* two divisions rounded up */
- num_bands = (int)( ( count + band_size - 1) / band_size );
- band_size = ( count + num_bands - 1 ) / num_bands;
+ n = ( height + n - 1 ) / n;
+ height = ( height + n - 1 ) / n;
}
- min = ras.min_ey;
- max_y = ras.max_ey;
+ /* memory management */
+ n = ( height * sizeof ( PCell ) + sizeof ( TCell ) - 1 ) / sizeof ( TCell );
+
+ ras.cells = buffer + n;
+ ras.max_cells = (FT_PtrDist)( FT_MAX_GRAY_POOL - n );
+ ras.ycells = (PCell*)buffer;
- for ( ; min < max_y; min = max )
+ for ( y = yMin; y < yMax; )
{
- max = min + band_size;
- if ( max > max_y )
- max = max_y;
+ ras.min_ey = y;
+ y += height;
+ ras.max_ey = FT_MIN( y, yMax );
band = bands;
- band[1] = min;
- band[0] = max;
+ band[1] = xMin;
+ band[0] = xMax;
do
{
@@ -1765,27 +1783,12 @@ typedef ptrdiff_t FT_PtrDist;
int error;
- /* memory management */
- {
- size_t ycount = (size_t)width;
- size_t cell_start;
-
-
- cell_start = ( ycount * sizeof ( PCell ) + sizeof ( TCell ) - 1 ) /
- sizeof ( TCell );
-
- ras.cells = buffer + cell_start;
- ras.max_cells = (FT_PtrDist)( FT_MAX_GRAY_POOL - cell_start );
- ras.num_cells = 0;
-
- ras.ycells = (PCell*)buffer;
- while ( ycount )
- ras.ycells[--ycount] = NULL;
- }
+ FT_MEM_ZERO( ras.ycells, height * sizeof ( PCell ) );
+ ras.num_cells = 0;
ras.invalid = 1;
- ras.min_ey = band[1];
- ras.max_ey = band[0];
+ ras.min_ex = band[1];
+ ras.max_ex = band[0];
error = gray_convert_glyph_inner( RAS_VAR );
@@ -1801,8 +1804,7 @@ typedef ptrdiff_t FT_PtrDist;
/* render pool overflow; we will reduce the render band by half */
width >>= 1;
- /* This is too complex for a single scanline; there must */
- /* be some problems. */
+ /* this should never happen even with tiny rendering pool */
if ( width == 0 )
{
FT_TRACE7(( "gray_convert_glyph: rotten glyph\n" ));