[base, smooth] LCD filtering cleanups.
* src/base/ftlcdlil.c (ft_lcd_filter_fir, _ft_lcd_filter_legacy):
Clean up, start filtering from the bottom-left origin.
* src/smooth/ftsmooth.c (ft_smooth_render_generic): Updated.
diff --git a/ChangeLog b/ChangeLog
index 90247f9..b5069b1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2017-06-17 Alexei Podtelezhnikov <apodtele@gmail.com>
+
+ [base, smooth] LCD filtering cleanups.
+
+ * src/base/ftlcdlil.c (ft_lcd_filter_fir, _ft_lcd_filter_legacy):
+ Clean up, start filtering from the bottom-left origin.
+
+ * src/smooth/ftsmooth.c (ft_smooth_render_generic): Updated.
+
2017-06-16 Werner Lemberg <wl@gnu.org>
[truetype] Integer overflows.
diff --git a/src/base/ftlcdfil.c b/src/base/ftlcdfil.c
index 65dbf34..6d35e35 100644
--- a/src/base/ftlcdfil.c
+++ b/src/base/ftlcdfil.c
@@ -35,135 +35,113 @@
FT_Render_Mode mode,
FT_LcdFiveTapFilter weights )
{
- FT_UInt width = (FT_UInt)bitmap->width;
- FT_UInt height = (FT_UInt)bitmap->rows;
+ FT_UInt width = (FT_UInt)bitmap->width;
+ FT_UInt height = (FT_UInt)bitmap->rows;
+ FT_Int pitch = bitmap->pitch;
+ FT_Byte* origin = bitmap->buffer;
+ /* take care of bitmap flow */
+ if ( pitch > 0 )
+ origin += pitch * (FT_Int)( height - 1 );
+
/* horizontal in-place FIR filter */
- if ( mode == FT_RENDER_MODE_LCD && width >= 4 )
+ if ( mode == FT_RENDER_MODE_LCD && width >= 2 )
{
- FT_Byte* line = bitmap->buffer;
+ FT_Byte* line = origin;
- /* take care of bitmap flow */
- if ( bitmap->pitch < 0 )
- line -= bitmap->pitch * (FT_Int)( bitmap->rows - 1 );
+ /* `fir' must be at least 32 bit wide, since the sum of */
+ /* the values in `weights' can exceed 0xFF */
- /* `fir' and `pix' must be at least 32 bit wide, since the sum of */
- /* the values in `weights' can exceed 0xFF */
-
- for ( ; height > 0; height--, line += bitmap->pitch )
+ for ( ; height > 0; height--, line -= pitch )
{
- FT_UInt fir[4]; /* below, `pix' is used as the 5th element */
- FT_UInt val1, xx;
+ FT_UInt fir[5];
+ FT_UInt val, xx;
- val1 = line[0];
- fir[0] = weights[2] * val1;
- fir[1] = weights[3] * val1;
- fir[2] = weights[4] * val1;
- fir[3] = 0;
+ val = line[0];
+ fir[2] = weights[2] * val;
+ fir[3] = weights[3] * val;
+ fir[4] = weights[4] * val;
- val1 = line[1];
- fir[0] += weights[1] * val1;
- fir[1] += weights[2] * val1;
- fir[2] += weights[3] * val1;
- fir[3] += weights[4] * val1;
+ val = line[1];
+ fir[1] = fir[2] + weights[1] * val;
+ fir[2] = fir[3] + weights[2] * val;
+ fir[3] = fir[4] + weights[3] * val;
+ fir[4] = weights[4] * val;
for ( xx = 2; xx < width; xx++ )
{
- FT_UInt val, pix;
-
-
val = line[xx];
- pix = fir[0] + weights[0] * val;
- fir[0] = fir[1] + weights[1] * val;
- fir[1] = fir[2] + weights[2] * val;
- fir[2] = fir[3] + weights[3] * val;
- fir[3] = weights[4] * val;
+ fir[0] = fir[1] + weights[0] * val;
+ fir[1] = fir[2] + weights[1] * val;
+ fir[2] = fir[3] + weights[2] * val;
+ fir[3] = fir[4] + weights[3] * val;
+ fir[4] = weights[4] * val;
- pix >>= 8;
- pix |= (FT_UInt)-(FT_Int)( pix >> 8 );
- line[xx - 2] = (FT_Byte)pix;
+ fir[0] >>= 8;
+ fir[0] |= (FT_UInt)-(FT_Int)( fir[0] >> 8 );
+ line[xx - 2] = (FT_Byte)fir[0];
}
- {
- FT_UInt pix;
+ fir[1] >>= 8;
+ fir[1] |= (FT_UInt)-(FT_Int)( fir[1] >> 8 );
+ line[xx - 2] = (FT_Byte)fir[1];
-
- pix = fir[0] >> 8;
- pix |= (FT_UInt)-(FT_Int)( pix >> 8 );
- line[xx - 2] = (FT_Byte)pix;
-
- pix = fir[1] >> 8;
- pix |= (FT_UInt)-(FT_Int)( pix >> 8 );
- line[xx - 1] = (FT_Byte)pix;
- }
+ fir[2] >>= 8;
+ fir[2] |= (FT_UInt)-(FT_Int)( fir[2] >> 8 );
+ line[xx - 1] = (FT_Byte)fir[2];
}
}
/* vertical in-place FIR filter */
- else if ( mode == FT_RENDER_MODE_LCD_V && height >= 4 )
+ else if ( mode == FT_RENDER_MODE_LCD_V && height >= 2 )
{
- FT_Byte* column = bitmap->buffer;
- FT_Int pitch = bitmap->pitch;
+ FT_Byte* column = origin;
- /* take care of bitmap flow */
- if ( bitmap->pitch < 0 )
- column -= bitmap->pitch * (FT_Int)( bitmap->rows - 1 );
-
for ( ; width > 0; width--, column++ )
{
FT_Byte* col = column;
- FT_UInt fir[4]; /* below, `pix' is used as the 5th element */
- FT_UInt val1, yy;
+ FT_UInt fir[5];
+ FT_UInt val, yy;
- val1 = col[0];
- fir[0] = weights[2] * val1;
- fir[1] = weights[3] * val1;
- fir[2] = weights[4] * val1;
- fir[3] = 0;
- col += pitch;
+ val = col[0];
+ fir[2] = weights[2] * val;
+ fir[3] = weights[3] * val;
+ fir[4] = weights[4] * val;
+ col -= pitch;
- val1 = col[0];
- fir[0] += weights[1] * val1;
- fir[1] += weights[2] * val1;
- fir[2] += weights[3] * val1;
- fir[3] += weights[4] * val1;
- col += pitch;
+ val = col[0];
+ fir[1] = fir[2] + weights[1] * val;
+ fir[2] = fir[3] + weights[2] * val;
+ fir[3] = fir[4] + weights[3] * val;
+ fir[4] = weights[4] * val;
+ col -= pitch;
- for ( yy = 2; yy < height; yy++ )
+ for ( yy = 2; yy < height; yy++, col -= pitch )
{
- FT_UInt val, pix;
-
-
val = col[0];
- pix = fir[0] + weights[0] * val;
- fir[0] = fir[1] + weights[1] * val;
- fir[1] = fir[2] + weights[2] * val;
- fir[2] = fir[3] + weights[3] * val;
- fir[3] = weights[4] * val;
+ fir[0] = fir[1] + weights[0] * val;
+ fir[1] = fir[2] + weights[1] * val;
+ fir[2] = fir[3] + weights[2] * val;
+ fir[3] = fir[4] + weights[3] * val;
+ fir[4] = weights[4] * val;
- pix >>= 8;
- pix |= (FT_UInt)-(FT_Int)( pix >> 8 );
- col[-2 * pitch] = (FT_Byte)pix;
- col += pitch;
+ fir[0] >>= 8;
+ fir[0] |= (FT_UInt)-(FT_Int)( fir[0] >> 8 );
+ col[pitch * 2] = (FT_Byte)fir[0];
}
- {
- FT_UInt pix;
+ fir[1] >>= 8;
+ fir[1] |= (FT_UInt)-(FT_Int)( fir[1] >> 8 );
+ col[pitch * 2] = (FT_Byte)fir[1];
-
- pix = fir[0] >> 8;
- pix |= (FT_UInt)-(FT_Int)( pix >> 8 );
- col[-2 * pitch] = (FT_Byte)pix;
-
- pix = fir[1] >> 8;
- pix |= (FT_UInt)-(FT_Int)( pix >> 8 );
- col[-pitch] = (FT_Byte)pix;
- }
+ fir[2] >>= 8;
+ fir[2] |= (FT_UInt)-(FT_Int)( fir[2] >> 8 );
+ col[pitch] = (FT_Byte)fir[2];
}
}
}
@@ -177,9 +155,10 @@
FT_Render_Mode mode,
FT_Byte* weights )
{
- FT_UInt width = (FT_UInt)bitmap->width;
- FT_UInt height = (FT_UInt)bitmap->rows;
- FT_Int pitch = bitmap->pitch;
+ FT_UInt width = (FT_UInt)bitmap->width;
+ FT_UInt height = (FT_UInt)bitmap->rows;
+ FT_Int pitch = bitmap->pitch;
+ FT_Byte* origin = bitmap->buffer;
static const unsigned int filters[3][3] =
{
@@ -191,33 +170,31 @@
FT_UNUSED( weights );
+ /* take care of bitmap flow */
+ if ( pitch > 0 )
+ origin += pitch * (FT_Int)( height - 1 );
+
/* horizontal in-place intra-pixel filter */
if ( mode == FT_RENDER_MODE_LCD && width >= 3 )
{
- FT_Byte* line = bitmap->buffer;
+ FT_Byte* line = origin;
- /* take care of bitmap flow */
- if ( bitmap->pitch < 0 )
- line -= bitmap->pitch * (FT_Int)( bitmap->rows - 1 );
-
- for ( ; height > 0; height--, line += pitch )
+ for ( ; height > 0; height--, line -= pitch )
{
FT_UInt xx;
for ( xx = 0; xx < width; xx += 3 )
{
- FT_UInt r = 0;
- FT_UInt g = 0;
- FT_UInt b = 0;
+ FT_UInt r, g, b;
FT_UInt p;
p = line[xx];
- r += filters[0][0] * p;
- g += filters[0][1] * p;
- b += filters[0][2] * p;
+ r = filters[0][0] * p;
+ g = filters[0][1] * p;
+ b = filters[0][2] * p;
p = line[xx + 1];
r += filters[1][0] * p;
@@ -237,31 +214,24 @@
}
else if ( mode == FT_RENDER_MODE_LCD_V && height >= 3 )
{
- FT_Byte* column = bitmap->buffer;
+ FT_Byte* column = origin;
- /* take care of bitmap flow */
- if ( bitmap->pitch < 0 )
- column -= bitmap->pitch * (FT_Int)( bitmap->rows - 1 );
-
for ( ; width > 0; width--, column++ )
{
- FT_Byte* col = column;
- FT_Byte* col_end = col + (FT_Int)height * pitch;
+ FT_Byte* col = column - 2 * pitch;
- for ( ; col < col_end; col += 3 * pitch )
+ for ( ; height > 0; height -= 3, col -= 3 * pitch )
{
- FT_UInt r = 0;
- FT_UInt g = 0;
- FT_UInt b = 0;
+ FT_UInt r, g, b;
FT_UInt p;
p = col[0];
- r += filters[0][0] * p;
- g += filters[0][1] * p;
- b += filters[0][2] * p;
+ r = filters[0][0] * p;
+ g = filters[0][1] * p;
+ b = filters[0][2] * p;
p = col[pitch];
r += filters[1][0] * p;
@@ -275,7 +245,7 @@
col[0] = (FT_Byte)( r / 65536 );
col[pitch] = (FT_Byte)( g / 65536 );
- col[2 * pitch] = (FT_Byte)( b / 65536 );
+ col[pitch * 2] = (FT_Byte)( b / 65536 );
}
}
}
diff --git a/src/smooth/ftsmooth.c b/src/smooth/ftsmooth.c
index 061d251..fd12e66 100644
--- a/src/smooth/ftsmooth.c
+++ b/src/smooth/ftsmooth.c
@@ -207,10 +207,10 @@
if ( vmul )
{
- cbox.yMax += lcd_weights[0] ? 43
- : lcd_weights[1] ? 22 : 0;
- cbox.yMin -= lcd_weights[4] ? 43
+ cbox.yMax += lcd_weights[4] ? 43
: lcd_weights[3] ? 22 : 0;
+ cbox.yMin -= lcd_weights[0] ? 43
+ : lcd_weights[1] ? 22 : 0;
}
}
#endif
