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-rw-r--r--src/3rdparty/freetype/src/base/ftlcdfil.c315
1 files changed, 150 insertions, 165 deletions
diff --git a/src/3rdparty/freetype/src/base/ftlcdfil.c b/src/3rdparty/freetype/src/base/ftlcdfil.c
index ff6f7e98ce..8d314df080 100644
--- a/src/3rdparty/freetype/src/base/ftlcdfil.c
+++ b/src/3rdparty/freetype/src/base/ftlcdfil.c
@@ -4,7 +4,7 @@
/* */
/* FreeType API for color filtering of subpixel bitmap glyphs (body). */
/* */
-/* Copyright 2006-2015 by */
+/* Copyright 2006-2018 by */
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
/* */
/* This file is part of the FreeType project, and may only be used, */
@@ -29,142 +29,140 @@
/* define USE_LEGACY to implement the legacy filter */
#define USE_LEGACY
- /* FIR filter used by the default and light filters */
- static void
- _ft_lcd_filter_fir( FT_Bitmap* bitmap,
- FT_Render_Mode mode,
- FT_Library library )
+#define FT_SHIFTCLAMP( x ) ( x >>= 8, (FT_Byte)( x > 255 ? 255 : x ) )
+
+
+ /* add padding according to filter weights */
+ FT_BASE_DEF (void)
+ ft_lcd_padding( FT_Pos* Min,
+ FT_Pos* Max,
+ FT_GlyphSlot slot )
{
- FT_Byte* weights = library->lcd_weights;
- FT_UInt width = (FT_UInt)bitmap->width;
- FT_UInt height = (FT_UInt)bitmap->rows;
+ FT_Byte* lcd_weights;
+ FT_Bitmap_LcdFilterFunc lcd_filter_func;
- /* horizontal in-place FIR filter */
- if ( mode == FT_RENDER_MODE_LCD && width >= 4 )
+ /* Per-face LCD filtering takes priority if set up. */
+ if ( slot->face && slot->face->internal->lcd_filter_func )
+ {
+ lcd_weights = slot->face->internal->lcd_weights;
+ lcd_filter_func = slot->face->internal->lcd_filter_func;
+ }
+ else
{
- FT_Byte* line = bitmap->buffer;
+ lcd_weights = slot->library->lcd_weights;
+ lcd_filter_func = slot->library->lcd_filter_func;
+ }
+ if ( lcd_filter_func == ft_lcd_filter_fir )
+ {
+ *Min -= lcd_weights[0] ? 43 :
+ lcd_weights[1] ? 22 : 0;
+ *Max += lcd_weights[4] ? 43 :
+ lcd_weights[3] ? 22 : 0;
+ }
+ }
- /* take care of bitmap flow */
- if ( bitmap->pitch < 0 )
- line -= bitmap->pitch * (FT_Int)( bitmap->rows - 1 );
- /* `fir' and `pix' must be at least 32 bit wide, since the sum of */
- /* the values in `weights' can exceed 0xFF */
+ /* FIR filter used by the default and light filters */
+ FT_BASE_DEF( void )
+ ft_lcd_filter_fir( FT_Bitmap* bitmap,
+ FT_Render_Mode mode,
+ FT_LcdFiveTapFilter weights )
+ {
+ FT_UInt width = (FT_UInt)bitmap->width;
+ FT_UInt height = (FT_UInt)bitmap->rows;
+ FT_Int pitch = bitmap->pitch;
+ FT_Byte* origin = bitmap->buffer;
- for ( ; height > 0; height--, line += bitmap->pitch )
- {
- FT_UInt fir[4]; /* below, `pix' is used as the 5th element */
- FT_UInt val1, xx;
+ /* take care of bitmap flow */
+ if ( pitch > 0 && height > 0 )
+ origin += pitch * (FT_Int)( height - 1 );
- val1 = line[0];
- fir[0] = weights[2] * val1;
- fir[1] = weights[3] * val1;
- fir[2] = weights[4] * val1;
- fir[3] = 0;
+ /* horizontal in-place FIR filter */
+ if ( mode == FT_RENDER_MODE_LCD && width >= 2 )
+ {
+ FT_Byte* line = origin;
- val1 = line[1];
- fir[0] += weights[1] * val1;
- fir[1] += weights[2] * val1;
- fir[2] += weights[3] * val1;
- fir[3] += weights[4] * val1;
- for ( xx = 2; xx < width; xx++ )
- {
- FT_UInt val, pix;
+ /* `fir' must be at least 32 bit wide, since the sum of */
+ /* the values in `weights' can exceed 0xFF */
+ for ( ; height > 0; height--, line -= pitch )
+ {
+ FT_UInt fir[5];
+ FT_UInt val, xx;
- 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;
-
- pix >>= 8;
- pix |= (FT_UInt)-(FT_Int)( pix >> 8 );
- line[xx - 2] = (FT_Byte)pix;
- }
- {
- FT_UInt pix;
+ val = line[0];
+ fir[2] = weights[2] * val;
+ fir[3] = weights[3] * val;
+ fir[4] = weights[4] * val;
+ 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;
- pix = fir[0] >> 8;
- pix |= (FT_UInt)-(FT_Int)( pix >> 8 );
- line[xx - 2] = (FT_Byte)pix;
+ for ( xx = 2; xx < width; xx++ )
+ {
+ val = line[xx];
+ 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 = fir[1] >> 8;
- pix |= (FT_UInt)-(FT_Int)( pix >> 8 );
- line[xx - 1] = (FT_Byte)pix;
+ line[xx - 2] = FT_SHIFTCLAMP( fir[0] );
}
+
+ line[xx - 2] = FT_SHIFTCLAMP( fir[1] );
+ line[xx - 1] = FT_SHIFTCLAMP( 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;
-
- pix >>= 8;
- pix |= (FT_UInt)-(FT_Int)( pix >> 8 );
- col[-2 * pitch] = (FT_Byte)pix;
- col += pitch;
- }
-
- {
- FT_UInt pix;
+ 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 = 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;
+ col[pitch * 2] = FT_SHIFTCLAMP( fir[0] );
}
+
+ col[pitch * 2] = FT_SHIFTCLAMP( fir[1] );
+ col[pitch] = FT_SHIFTCLAMP( fir[2] );
}
}
}
@@ -176,11 +174,12 @@
static void
_ft_lcd_filter_legacy( FT_Bitmap* bitmap,
FT_Render_Mode mode,
- FT_Library library )
+ 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] =
{
@@ -189,36 +188,34 @@
{ 65538 * 1/13, 65538 * 1/6, 65538 * 9/13 }
};
- FT_UNUSED( library );
+ FT_UNUSED( weights );
+ /* take care of bitmap flow */
+ if ( pitch > 0 && height > 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;
@@ -238,31 +235,24 @@
}
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;
@@ -276,7 +266,7 @@
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 );
}
}
}
@@ -295,7 +285,8 @@
if ( !weights )
return FT_THROW( Invalid_Argument );
- ft_memcpy( library->lcd_weights, weights, 5 );
+ ft_memcpy( library->lcd_weights, weights, FT_LCD_FILTER_FIVE_TAPS );
+ library->lcd_filter_func = ft_lcd_filter_fir;
return FT_Err_Ok;
}
@@ -305,12 +296,10 @@
FT_Library_SetLcdFilter( FT_Library library,
FT_LcdFilter filter )
{
- static const FT_Byte light_filter[5] =
- { 0x00, 0x55, 0x56, 0x55, 0x00 };
- /* the values here sum up to a value larger than 256, */
- /* providing a cheap gamma correction */
- static const FT_Byte default_filter[5] =
- { 0x10, 0x40, 0x70, 0x40, 0x10 };
+ static const FT_LcdFiveTapFilter default_weights =
+ { 0x08, 0x4d, 0x56, 0x4d, 0x08 };
+ static const FT_LcdFiveTapFilter light_weights =
+ { 0x00, 0x55, 0x56, 0x55, 0x00 };
if ( !library )
@@ -320,42 +309,27 @@
{
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 )
-
- ft_memcpy( library->lcd_weights, light_filter, 5 );
- library->lcd_filter_func = _ft_lcd_filter_fir;
- library->lcd_extra = 2;
-
-#else
-
- ft_memcpy( library->lcd_weights, default_filter, 5 );
- library->lcd_filter_func = _ft_lcd_filter_fir;
- library->lcd_extra = 2;
-
-#endif
-
+ ft_memcpy( library->lcd_weights,
+ default_weights,
+ FT_LCD_FILTER_FIVE_TAPS );
+ library->lcd_filter_func = ft_lcd_filter_fir;
break;
case FT_LCD_FILTER_LIGHT:
- ft_memcpy( library->lcd_weights, light_filter, 5 );
- library->lcd_filter_func = _ft_lcd_filter_fir;
- library->lcd_extra = 2;
+ ft_memcpy( library->lcd_weights,
+ light_weights,
+ FT_LCD_FILTER_FIVE_TAPS );
+ library->lcd_filter_func = ft_lcd_filter_fir;
break;
#ifdef USE_LEGACY
case FT_LCD_FILTER_LEGACY:
+ case FT_LCD_FILTER_LEGACY1:
library->lcd_filter_func = _ft_lcd_filter_legacy;
- library->lcd_extra = 0;
break;
#endif
@@ -364,13 +338,24 @@
return FT_THROW( Invalid_Argument );
}
- library->lcd_filter = filter;
-
return FT_Err_Ok;
}
#else /* !FT_CONFIG_OPTION_SUBPIXEL_RENDERING */
+ /* add padding according to accommodate outline shifts */
+ FT_BASE_DEF (void)
+ ft_lcd_padding( FT_Pos* Min,
+ FT_Pos* Max,
+ FT_GlyphSlot slot )
+ {
+ FT_UNUSED( slot );
+
+ *Min -= 21;
+ *Max += 21;
+ }
+
+
FT_EXPORT_DEF( FT_Error )
FT_Library_SetLcdFilterWeights( FT_Library library,
unsigned char *weights )
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-27 16:33:27 +0000