From 6bf0a5cb5034a7e684dcc3500e841785237ce2dd Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 19:32:43 +0200 Subject: Adding upstream version 1:115.7.0. Signed-off-by: Daniel Baumann --- modules/freetype2/src/base/ftlcdfil.c | 437 ++++++++++++++++++++++++++++++++++ 1 file changed, 437 insertions(+) create mode 100644 modules/freetype2/src/base/ftlcdfil.c (limited to 'modules/freetype2/src/base/ftlcdfil.c') diff --git a/modules/freetype2/src/base/ftlcdfil.c b/modules/freetype2/src/base/ftlcdfil.c new file mode 100644 index 0000000000..6c3fd66e0b --- /dev/null +++ b/modules/freetype2/src/base/ftlcdfil.c @@ -0,0 +1,437 @@ +/**************************************************************************** + * + * ftlcdfil.c + * + * FreeType API for color filtering of subpixel bitmap glyphs (body). + * + * Copyright (C) 2006-2023 by + * David Turner, Robert Wilhelm, and Werner Lemberg. + * + * This file is part of the FreeType project, and may only be used, + * modified, and distributed under the terms of the FreeType project + * license, LICENSE.TXT. By continuing to use, modify, or distribute + * this file you indicate that you have read the license and + * understand and accept it fully. + * + */ + + +#include + +#include +#include +#include + + +#ifdef FT_CONFIG_OPTION_SUBPIXEL_RENDERING + +/* define USE_LEGACY to implement the legacy filter */ +#define USE_LEGACY + +#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_BBox* cbox, + FT_GlyphSlot slot, + FT_Render_Mode mode ) + { + FT_Byte* lcd_weights; + FT_Bitmap_LcdFilterFunc lcd_filter_func; + + + /* 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 + { + lcd_weights = slot->library->lcd_weights; + lcd_filter_func = slot->library->lcd_filter_func; + } + + if ( lcd_filter_func == ft_lcd_filter_fir ) + { + if ( mode == FT_RENDER_MODE_LCD ) + { + cbox->xMin -= lcd_weights[0] ? 43 : + lcd_weights[1] ? 22 : 0; + cbox->xMax += lcd_weights[4] ? 43 : + lcd_weights[3] ? 22 : 0; + } + else if ( mode == FT_RENDER_MODE_LCD_V ) + { + cbox->yMin -= lcd_weights[0] ? 43 : + lcd_weights[1] ? 22 : 0; + cbox->yMax += lcd_weights[4] ? 43 : + lcd_weights[3] ? 22 : 0; + } + } + } + + + /* FIR filter used by the default and light filters */ + FT_BASE_DEF( void ) + ft_lcd_filter_fir( FT_Bitmap* bitmap, + 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; + FT_Byte mode = bitmap->pixel_mode; + + + /* take care of bitmap flow */ + if ( pitch > 0 && height > 0 ) + origin += pitch * (FT_Int)( height - 1 ); + + /* horizontal in-place FIR filter */ + if ( mode == FT_PIXEL_MODE_LCD && width >= 2 ) + { + FT_Byte* line = origin; + + + /* `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[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; + + 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; + + 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_PIXEL_MODE_LCD_V && height >= 2 ) + { + FT_Byte* column = origin; + + + for ( ; width > 0; width--, column++ ) + { + FT_Byte* col = column; + FT_UInt fir[5]; + FT_UInt val, yy; + + + val = col[0]; + fir[2] = weights[2] * val; + fir[3] = weights[3] * val; + fir[4] = weights[4] * val; + 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++, col -= pitch ) + { + val = col[0]; + 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; + + col[pitch * 2] = FT_SHIFTCLAMP( fir[0] ); + } + + col[pitch * 2] = FT_SHIFTCLAMP( fir[1] ); + col[pitch] = FT_SHIFTCLAMP( fir[2] ); + } + } + } + + +#ifdef USE_LEGACY + + /* intra-pixel filter used by the legacy filter */ + static void + _ft_lcd_filter_legacy( FT_Bitmap* bitmap, + FT_Byte* 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; + FT_Byte mode = bitmap->pixel_mode; + + static const unsigned 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 } + }; + + 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_PIXEL_MODE_LCD && width >= 3 ) + { + FT_Byte* line = origin; + + + for ( ; height > 0; height--, line -= pitch ) + { + FT_UInt xx; + + + for ( xx = 0; xx < width; xx += 3 ) + { + 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; + + 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; + + line[xx] = (FT_Byte)( r / 65536 ); + line[xx + 1] = (FT_Byte)( g / 65536 ); + line[xx + 2] = (FT_Byte)( b / 65536 ); + } + } + } + else if ( mode == FT_PIXEL_MODE_LCD_V && height >= 3 ) + { + FT_Byte* column = origin; + + + for ( ; width > 0; width--, column++ ) + { + FT_Byte* col = column - 2 * pitch; + + + for ( ; height > 0; height -= 3, col -= 3 * pitch ) + { + 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; + + 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; + + col[0] = (FT_Byte)( r / 65536 ); + col[pitch] = (FT_Byte)( g / 65536 ); + col[pitch * 2] = (FT_Byte)( b / 65536 ); + } + } + } + } + +#endif /* USE_LEGACY */ + + + /* documentation in ftlcdfil.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Library_SetLcdFilterWeights( FT_Library library, + unsigned char *weights ) + { + if ( !library ) + return FT_THROW( Invalid_Library_Handle ); + + if ( !weights ) + return FT_THROW( Invalid_Argument ); + + ft_memcpy( library->lcd_weights, weights, FT_LCD_FILTER_FIVE_TAPS ); + library->lcd_filter_func = ft_lcd_filter_fir; + + return FT_Err_Ok; + } + + + /* documentation in ftlcdfil.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Library_SetLcdFilter( FT_Library library, + FT_LcdFilter filter ) + { + static const FT_LcdFiveTapFilter default_weights = + { 0x08, 0x4d, 0x56, 0x4d, 0x08 }; + static const FT_LcdFiveTapFilter light_weights = + { 0x00, 0x55, 0x56, 0x55, 0x00 }; + + + if ( !library ) + return FT_THROW( Invalid_Library_Handle ); + + switch ( filter ) + { + case FT_LCD_FILTER_NONE: + library->lcd_filter_func = NULL; + break; + + case FT_LCD_FILTER_DEFAULT: + 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_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; + break; + +#endif + + default: + return FT_THROW( Invalid_Argument ); + } + + return FT_Err_Ok; + } + + + FT_EXPORT_DEF( FT_Error ) + FT_Library_SetLcdGeometry( FT_Library library, + FT_Vector sub[3] ) + { + FT_UNUSED( library ); + FT_UNUSED( sub ); + + return FT_THROW( Unimplemented_Feature ); + } + +#else /* !FT_CONFIG_OPTION_SUBPIXEL_RENDERING */ + + /* add padding to accommodate outline shifts */ + FT_BASE_DEF( void ) + ft_lcd_padding( FT_BBox* cbox, + FT_GlyphSlot slot, + FT_Render_Mode mode ) + { + FT_Vector* sub = slot->library->lcd_geometry; + + if ( mode == FT_RENDER_MODE_LCD ) + { + cbox->xMin -= FT_MAX( FT_MAX( sub[0].x, sub[1].x ), sub[2].x ); + cbox->xMax -= FT_MIN( FT_MIN( sub[0].x, sub[1].x ), sub[2].x ); + cbox->yMin -= FT_MAX( FT_MAX( sub[0].y, sub[1].y ), sub[2].y ); + cbox->yMax -= FT_MIN( FT_MIN( sub[0].y, sub[1].y ), sub[2].y ); + } + else if ( mode == FT_RENDER_MODE_LCD_V ) + { + cbox->xMin -= FT_MAX( FT_MAX( sub[0].y, sub[1].y ), sub[2].y ); + cbox->xMax -= FT_MIN( FT_MIN( sub[0].y, sub[1].y ), sub[2].y ); + cbox->yMin += FT_MIN( FT_MIN( sub[0].x, sub[1].x ), sub[2].x ); + cbox->yMax += FT_MAX( FT_MAX( sub[0].x, sub[1].x ), sub[2].x ); + } + } + + + FT_EXPORT_DEF( FT_Error ) + FT_Library_SetLcdFilterWeights( FT_Library library, + unsigned char *weights ) + { + FT_UNUSED( library ); + FT_UNUSED( weights ); + + return FT_THROW( Unimplemented_Feature ); + } + + + FT_EXPORT_DEF( FT_Error ) + FT_Library_SetLcdFilter( FT_Library library, + FT_LcdFilter filter ) + { + FT_UNUSED( library ); + FT_UNUSED( filter ); + + return FT_THROW( Unimplemented_Feature ); + } + + + /* documentation in ftlcdfil.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Library_SetLcdGeometry( FT_Library library, + FT_Vector sub[3] ) + { + if ( !library ) + return FT_THROW( Invalid_Library_Handle ); + + if ( !sub ) + return FT_THROW( Invalid_Argument ); + + ft_memcpy( library->lcd_geometry, sub, 3 * sizeof( FT_Vector ) ); + + return FT_Err_Ok; + } + +#endif /* !FT_CONFIG_OPTION_SUBPIXEL_RENDERING */ + + +/* END */ -- cgit v1.2.3