ref: 0d0d78dadc9ae38aa0aafbddb5f08d381b7d27cc
parent: a95e5c62decad738707748efe78f8dba349c6d51
author: Werner Lemberg <[email protected]>
date: Tue Nov 14 05:37:10 EST 2006
formatting
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,28 +1,48 @@
2006-11-13 David Turner <[email protected]>
- * src/truetype/ttinterp.c: undefined the FIX_BYTECODE macro,
- since the interpreter "enhancements" are still too buggy for
- general use
+ * src/truetype/ttinterp.c (FIX_BYTECODE): Undefine. The interpreter
+ `enhancements' are still too buggy for general use.
- * src/base/ftlcdfil.c: added support for FT_FORCE_LIGHT_LCD_FILTER
- and FT_FORCE_LEGACY_LCD_FILTER at compile time. Define these macros
- when building the library to change the default LCD filter to be
- used. This is only useful for experimentation
+ * src/base/ftlcdfil.c: Add support for FT_FORCE_LIGHT_LCD_FILTER and
+ FT_FORCE_LEGACY_LCD_FILTER at compile time. Define these macros
+ when building the library to change the default LCD filter to be
+ used. This is only useful for experimentation.
- * include/freetype/ftlcdfil.h: updating documentation
+ * include/freetype/ftlcdfil.h: Update documentation.
2006-11-10 David Turner <[email protected]>
- * include/freetype/ftlcdfil.h, include/internal/ftobjs.h,
- src/base/ftlcdfilt.c, src/smooth/ftsmooth.c: API change for
- the LCD filter, the FT_LcdFilter value is a enum describing
- which filter to apply, new values FT_LCD_FILTER_LIGHT and
- FT_LCD_FILTER_LEGACY (the latter implements the LibXft original
- algorithm which produces incredible color fringes for everything
- except very-well hinted text)
+ * src/smooth/ftsmooth.c: API change for the LCD
+ filter. The FT_LcdFilter value is an enumeration describing which
+ filter to apply, with new values FT_LCD_FILTER_LIGHT and
+ FT_LCD_FILTER_LEGACY (the latter implements the LibXft original
+ algorithm which produces strong color fringes for everything
+ except very-well hinted text).
- * src/autofit/aflatin.c: various tiny improvements that drastically
- improve the handling of serif fonts and of LCD/LCD_V hinting modes.
+ * include/freetype/ftlcdfil.h (FT_Library_SetLcdFilter): Change
+ second parameter to an enum type.
+
+ * src/base/ftlcdfil.c (USE_LEGACY): Define.
+ (_ft_lcd_filter): Rename to...
+ (_ft_lcd_filter_fir): This.
+ Update parameters.
+ (_ft_lcd_filter_legacy) [USE_LEGACY]: New filter function.
+ (FT_Library_Set_LcdFilter): Update parameters.
+ Handle new filter modes.
+
+ * include/internal/ftobjs.h: Include FT_LCD_FILTER_H.
+ (FT_Bitmap_LcdFilterFunc): Change third argument to `FT_Library'.
+ (FT_LibraryRec) [FT_CONFIG_OPTION_SUBPIXEL_RENDERING]: Add filtering
+ callback and update other fields.
+
+ * src/smooth/ftsmooth.c (ft_smooth_render_generic)
+ [FT_CONFIG_OPTION_SUBPIXEL_RENDERING]: Update.
+ Other minor improvements.
+
+ * src/autofit/aflatin.c: Various tiny improvements that drastically
+ improve the handling of serif fonts and of LCD/LCD_V hinting modes.
+ (af_latin_hints_compute_edges): Fix typo.
+ (af_latin_compute_stem_width): Take better care of diagonal stems.
2006-11-09 David Turner <[email protected]>
--- a/README
+++ b/README
@@ -51,7 +51,7 @@
----------------------------------------------------------------------
-Copyright 2001-2006 by
+Copyright 2006 by
David Turner, Robert Wilhelm, and Werner Lemberg.
This file is part of the FreeType project, and may only be used,
--- a/include/freetype/ftlcdfil.h
+++ b/include/freetype/ftlcdfil.h
@@ -27,40 +27,39 @@
FT_BEGIN_HEADER
- /****************************************************************************
- *
- * @func:
- * FT_LcdFilter
- *
- * @description:
- * a list of values used to identify various types of LCD filters
- *
- * @values:
- * FT_LCD_FILTER_NONE :: value 0 means do not perform filtering. when
- * used with subpixel rendering, this will result in sometimes severe
- * color fringes
- *
- * FT_LCD_FILTER_DEFAULT ::
- * the default filter reduces color fringes considerably, at the cost of
- * a slight bluriness in the output
- *
- * FT_LCD_FILTER_LIGHT ::
- * the light filter is a variant that produces less bluriness
- * at the cost of slightly more color fringes than the default one. It
- * might be better than the default one, depending on your monitor and
- * personal vision.
- *
- * FT_LCD_FILTER_LEGACY ::
- * this filter corresponds to the original libXft color filter, this
- * provides high contrast output, but can exhibit really bad color fringes
- * if your glyphs are not extremely well hinted to the pixel grid. In
- * other words, it only works well when enabling the TrueType bytecode
- * interpreter *and* using high-quality hinted fonts. It will suck for
- * all other cases.
- *
- * this filter is only provided for comparison purposes, and might be
- * disabled/unsupported in the future...
- */
+ /****************************************************************************
+ *
+ * @func:
+ * FT_LcdFilter
+ *
+ * @description:
+ * A list of values to identify various types of LCD filters.
+ *
+ * @values:
+ * FT_LCD_FILTER_NONE ::
+ * Do not perform filtering. When used with subpixel rendering, this
+ * results in sometimes severe color fringes.
+ *
+ * FT_LCD_FILTER_DEFAULT ::
+ * The default filter reduces color fringes considerably, at the cost
+ * of a slight blurriness in the output.
+ *
+ * FT_LCD_FILTER_LIGHT ::
+ * The light filter is a variant that produces less blurriness at the
+ * cost of slightly more color fringes than the default one. It might
+ * be better than the default one, depending on the monitor, personal
+ * vision, and taste.
+ *
+ * FT_LCD_FILTER_LEGACY ::
+ * This filter corresponds to the original libXft color filter. It
+ * provides high contrast output but can exhibit really bad color
+ * fringes if glyphs are not extremely well hinted to the pixel grid.
+ * In other words, it only works well if the TrueType bytecode
+ * interpreter is enabled *and* high-quality hinted fonts are used.
+ *
+ * This filter is only provided for comparison purposes, and might be
+ * disabled or stay unsupported in the future.
+ */
typedef enum
{FT_LCD_FILTER_NONE = 0,
@@ -84,9 +83,11 @@
* @FT_RENDER_MODE_LCD or @FT_RENDER_MODE_LCD_V.
*
* @input:
- * library :: A handle to the target library instance.
+ * library ::
+ * A handle to the target library instance.
*
- * filter :: filter type.
+ * filter ::
+ * The filter type.
*
* You can use @FT_LCD_FILTER_NONE here to disable this feature, or
* @FT_LCD_FILTER_DEFAULT to use a default filter that should work
@@ -97,8 +98,8 @@
*
* @note:
* This feature is always disabled by default. Clients must make an
- * explicit call to this function with a `filter' value other
- * than @FT_LCD_FILTER_NONE in order to enable it.
+ * explicit call to this function with a `filter' value other than
+ * @FT_LCD_FILTER_NONE in order to enable it.
*
* Due to *PATENTS* covering subpixel rendering, this function doesn't
* do anything except returning @FT_Err_Unimplemented_Feature if the
@@ -106,8 +107,8 @@
* defined in your build of the library, which should correspond to all
* default builds of the library.
*
- * The filter affects glyph bitmaps rendered through FT_Render_Glyph,
- * @@FT_Glyph_Get_Bitmap, @FT_Load_Glyph, and FT_Load_Char.
+ * The filter affects glyph bitmaps rendered through @FT_Render_Glyph,
+ * @FT_Glyph_Get_Bitmap, @FT_Load_Glyph, and @FT_Load_Char.
*
* It does _not_ affect the output of @FT_Outline_Render and
* @FT_Outline_Get_Bitmap.
--- a/src/autofit/aflatin.c
+++ b/src/autofit/aflatin.c
@@ -1538,6 +1538,7 @@
/* strong hinting process: snap the stem width to integer pixels */
FT_Pos org_dist = dist;
+
dist = af_latin_snap_width( axis->widths, axis->width_count, dist );
if ( vertical )
@@ -1573,14 +1574,15 @@
else if ( dist < 128 )
{- /* ok, we're only going to round to an integer width if
- * the corresponding distorsion is less than 1/4 pixel
- * otherwise, this really screws everything, since the
- * diagonals, which are not hinted, will appear a lot
- * more bolder or thinner than the vertical stems
- */
+ /* We only round to an integer width if the corresponding */
+ /* distortion is less than 1/4 pixel. Otherwise this */
+ /* makes everything worse since the diagonals, which are */
+ /* not hinted, appear a lot bolder or thinner than the */
+ /* vertical stems. */
+
FT_Int delta;
+
dist = ( dist + 22 ) & ~63;
delta = dist - org_dist;
if ( delta < 0 )
@@ -1590,7 +1592,7 @@
{dist = org_dist;
if ( dist < 48 )
- dist = (dist + 64) >> 1;
+ dist = ( dist + 64 ) >> 1;
}
}
else
--- a/src/base/ftlcdfil.c
+++ b/src/base/ftlcdfil.c
@@ -33,9 +33,9 @@
FT_Render_Mode mode,
FT_Library library )
{- FT_Byte* weights = library->lcd_weights;
- FT_UInt width = (FT_UInt)bitmap->width;
- FT_UInt height = (FT_UInt)bitmap->rows;
+ FT_Byte* weights = library->lcd_weights;
+ FT_UInt width = (FT_UInt)bitmap->width;
+ FT_UInt height = (FT_UInt)bitmap->rows;
/* horizontal in-place FIR filter */
@@ -160,6 +160,7 @@
#ifdef USE_LEGACY
+
/* FIR filter used by the default and light filters */
static void
_ft_lcd_filter_legacy( FT_Bitmap* bitmap,
@@ -166,19 +167,20 @@
FT_Render_Mode mode,
FT_Library library )
{- 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;
- static const int filters[3][3] =
+ static const int filters[3][3] =
{- { 65538*9/13, 65538*1/6, 65538*1/13 },- { 65538*3/13, 65538*4/6, 65538*3/13 },- { 65538*1/13, 65538*1/6, 65538*9/13 }+ { 65538 * 9/13, 65538 * 1/6, 65538 * 1/13 },+ { 65538 * 3/13, 65538 * 4/6, 65538 * 3/13 },+ { 65538 * 1/13, 65538 * 1/6, 65538 * 9/13 }};
- FT_UNUSED(library);
+ FT_UNUSED( library );
+
/* horizontal in-place FIR filter */
if ( mode == FT_RENDER_MODE_LCD && width >= 3 )
{@@ -189,6 +191,7 @@
{FT_UInt xx;
+
for ( xx = 0; xx < width; xx += 3 )
{FT_UInt r = 0;
@@ -196,37 +199,40 @@
FT_UInt b = 0;
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;
- g += filters[1][1]*p;
- b += filters[1][2]*p;
+ p = line[xx + 1];
+ r += filters[1][0] * p;
+ g += filters[1][1] * p;
+ b += filters[1][2] * p;
- p = line[xx+2];
- r += filters[2][0]*p;
- g += filters[2][1]*p;
- b += filters[2][2]*p;
+ p = line[xx + 2];
+ r += filters[2][0] * p;
+ g += filters[2][1] * p;
+ b += filters[2][2] * p;
- line[xx] = (FT_Byte)( r / 65536 );
- line[xx+1] = (FT_Byte)( g / 65536 );
- line[xx+2] = (FT_Byte)( b / 65536 );
+ line[xx] = (FT_Byte)( r / 65536 );
+ line[xx + 1] = (FT_Byte)( g / 65536 );
+ line[xx + 2] = (FT_Byte)( b / 65536 );
}
}
}
else if ( mode == FT_RENDER_MODE_LCD_V && height >= 3 )
{- FT_Byte* column = bitmap->buffer;
+ FT_Byte* column = bitmap->buffer;
+
for ( ; width > 0; width--, column++ )
{- FT_Byte* col = column;
- FT_Byte* col_end = col + height*pitch;
+ FT_Byte* col = column;
+ FT_Byte* col_end = col + height * pitch;
- for ( ; col < col_end; col += 3*pitch )
+
+ for ( ; col < col_end; col += 3 * pitch )
{FT_UInt r = 0;
FT_UInt g = 0;
@@ -233,76 +239,92 @@
FT_UInt b = 0;
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;
- g += filters[1][1]*p;
- b += filters[1][2]*p;
+ p = col[pitch];
+ r += filters[1][0] * p;
+ g += filters[1][1] * p;
+ b += filters[1][2] * p;
- p = col[pitch*2];
- r += filters[2][0]*p;
- g += filters[2][1]*p;
- b += filters[2][2]*p;
+ p = col[pitch * 2];
+ r += filters[2][0] * p;
+ g += filters[2][1] * p;
+ b += filters[2][2] * p;
- col[0] = (FT_Byte)( r / 65536 );
- col[pitch] = (FT_Byte)( g / 65536 );
- col[2*pitch] = (FT_Byte)( b / 65536 );
+ col[0] = (FT_Byte)( r / 65536 );
+ col[pitch] = (FT_Byte)( g / 65536 );
+ col[2 * pitch] = (FT_Byte)( b / 65536 );
}
}
}
}
+
#endif /* USE_LEGACY */
+
FT_EXPORT( FT_Error )
FT_Library_SetLcdFilter( FT_Library library,
FT_LcdFilter filter )
{- static const FT_Byte light_filter[5] = { 0, 85, 86, 85, 0 };- static const FT_Byte default_filter[5] = { 0x10, 0x40, 0x70, 0x40, 0x10 };+ static const FT_Byte light_filter[5] =
+ { 0, 85, 86, 85, 0 };+ static const FT_Byte default_filter[5] =
+ { 0x10, 0x40, 0x70, 0x40, 0x10 };+
if ( library == NULL )
return FT_Err_Invalid_Argument;
switch ( filter )
{- case FT_LCD_FILTER_NONE:
- library->lcd_filter_func = NULL;
- library->lcd_extra = 0;
- break;
+ case FT_LCD_FILTER_NONE:
+ library->lcd_filter_func = NULL;
+ library->lcd_extra = 0;
+ break;
- case FT_LCD_FILTER_DEFAULT:
-#if defined(FT_FORCE_LEGACY_LCD_FILTER)
- library->lcd_filter_func = _ft_lcd_filter_legacy;
- library->lcd_extra = 0;
-#elif defined(FT_FORCE_LIGHT_LCD_FILTER)
- memcpy( library->lcd_weights, default_filter, 5 );
- library->lcd_filter_func = _ft_lcd_filter_fir;
- library->lcd_extra = 2;
+ case FT_LCD_FILTER_DEFAULT:
+#if defined( FT_FORCE_LEGACY_LCD_FILTER )
+
+ library->lcd_filter_func = _ft_lcd_filter_legacy;
+ library->lcd_extra = 0;
+
+#elif defined( FT_FORCE_LIGHT_LCD_FILTER )
+
+ memcpy( library->lcd_weights, default_filter, 5 );
+ library->lcd_filter_func = _ft_lcd_filter_fir;
+ library->lcd_extra = 2;
+
#else
- memcpy( library->lcd_weights, default_filter, 5 );
- library->lcd_filter_func = _ft_lcd_filter_fir;
- library->lcd_extra = 2;
+
+ memcpy( library->lcd_weights, default_filter, 5 );
+ library->lcd_filter_func = _ft_lcd_filter_fir;
+ library->lcd_extra = 2;
+
#endif
- break;
- case FT_LCD_FILTER_LIGHT:
- memcpy( library->lcd_weights, light_filter, 5 );
- library->lcd_filter_func = _ft_lcd_filter_fir;
- library->lcd_extra = 2;
- break;
+ break;
+ case FT_LCD_FILTER_LIGHT:
+ memcpy( library->lcd_weights, light_filter, 5 );
+ library->lcd_filter_func = _ft_lcd_filter_fir;
+ library->lcd_extra = 2;
+ break;
+
#ifdef USE_LEGACY
- case FT_LCD_FILTER_LEGACY:
- library->lcd_filter_func = _ft_lcd_filter_legacy;
- library->lcd_extra = 0;
- break;
+
+ case FT_LCD_FILTER_LEGACY:
+ library->lcd_filter_func = _ft_lcd_filter_legacy;
+ library->lcd_extra = 0;
+ break;
+
#endif
- default:
- return FT_Err_Invalid_Argument;
+
+ default:
+ return FT_Err_Invalid_Argument;
}
library->lcd_filter = filter;
--- a/src/smooth/ftsmooth.c
+++ b/src/smooth/ftsmooth.c
@@ -175,18 +175,20 @@
{FT_Int extra = slot->library->lcd_extra;
+
if ( hmul )
{- x_shift -= 64*(extra >> 1);
- width += 3*extra;
+ x_shift -= 64 * ( extra >> 1 );
+ width += 3 * extra;
pitch = FT_PAD_CEIL( width, 4 );
- x_left -= (extra >> 1);
+ x_left -= extra >> 1;
}
+
if ( vmul )
{- y_shift -= 64*(extra >> 1);
- height += 3*extra;
- y_top += (extra >> 1);
+ y_shift -= 64 * ( extra >> 1 );
+ height += 3 * extra;
+ y_top += extra >> 1;
}
}