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diff --git a/modules/freetype2/src/base/ftlcdfil.c b/modules/freetype2/src/base/ftlcdfil.c
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+/****************************************************************************
+ *
+ * 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 <freetype/internal/ftdebug.h>
+
+#include <freetype/ftlcdfil.h>
+#include <freetype/ftimage.h>
+#include <freetype/internal/ftobjs.h>
+
+
+#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 */
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