| Index: third_party/freetype/include/ftlcdfil.h
|
| diff --git a/third_party/freetype/include/ftlcdfil.h b/third_party/freetype/include/ftlcdfil.h
|
| deleted file mode 100644
|
| index 39206f0192741b82836a3c66aa409f9074db9647..0000000000000000000000000000000000000000
|
| --- a/third_party/freetype/include/ftlcdfil.h
|
| +++ /dev/null
|
| @@ -1,251 +0,0 @@
|
| -/***************************************************************************/
|
| -/* */
|
| -/* ftlcdfil.h */
|
| -/* */
|
| -/* FreeType API for color filtering of subpixel bitmap glyphs */
|
| -/* (specification). */
|
| -/* */
|
| -/* Copyright 2006-2008, 2010, 2013 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. */
|
| -/* */
|
| -/***************************************************************************/
|
| -
|
| -
|
| -#ifndef __FT_LCD_FILTER_H__
|
| -#define __FT_LCD_FILTER_H__
|
| -
|
| -#include <ft2build.h>
|
| -#include FT_FREETYPE_H
|
| -
|
| -#ifdef FREETYPE_H
|
| -#error "freetype.h of FreeType 1 has been loaded!"
|
| -#error "Please fix the directory search order for header files"
|
| -#error "so that freetype.h of FreeType 2 is found first."
|
| -#endif
|
| -
|
| -
|
| -FT_BEGIN_HEADER
|
| -
|
| - /***************************************************************************
|
| - *
|
| - * @section:
|
| - * lcd_filtering
|
| - *
|
| - * @title:
|
| - * LCD Filtering
|
| - *
|
| - * @abstract:
|
| - * Reduce color fringes of LCD-optimized bitmaps.
|
| - *
|
| - * @description:
|
| - * The @FT_Library_SetLcdFilter API can be used to specify a low-pass
|
| - * filter, which is then applied to LCD-optimized bitmaps generated
|
| - * through @FT_Render_Glyph. This is useful to reduce color fringes
|
| - * that would occur with unfiltered rendering.
|
| - *
|
| - * Note that no filter is active by default, and that this function is
|
| - * *not* implemented in default builds of the library. You need to
|
| - * #define FT_CONFIG_OPTION_SUBPIXEL_RENDERING in your `ftoption.h' file
|
| - * in order to activate it.
|
| - *
|
| - * FreeType generates alpha coverage maps, which are linear by nature.
|
| - * For instance, the value 0x80 in bitmap representation means that
|
| - * (within numerical precision) 0x80/0xff fraction of that pixel is
|
| - * covered by the glyph's outline. The blending function for placing
|
| - * text over a background is
|
| - *
|
| - * {
|
| - * dst = alpha * src + (1 - alpha) * dst ,
|
| - * }
|
| - *
|
| - * which is known as OVER. However, when calculating the output of the
|
| - * OVER operator, the source colors should first be transformed to a
|
| - * linear color space, then alpha blended in that space, and transformed
|
| - * back to the output color space.
|
| - *
|
| - * When linear light blending is used, the default FIR5 filtering
|
| - * weights (as given by FT_LCD_FILTER_DEFAULT) are no longer optimal, as
|
| - * they have been designed for black on white rendering while lacking
|
| - * gamma correction. To preserve color neutrality, weights for a FIR5
|
| - * filter should be chosen according to two free parameters `a' and `c',
|
| - * and the FIR weights should be
|
| - *
|
| - * {
|
| - * [a - c, a + c, 2 * a, a + c, a - c] .
|
| - * }
|
| - *
|
| - * This formula generates equal weights for all the color primaries
|
| - * across the filter kernel, which makes it colorless. One suggested
|
| - * set of weights is
|
| - *
|
| - * {
|
| - * [0x10, 0x50, 0x60, 0x50, 0x10] ,
|
| - * }
|
| - *
|
| - * where `a' has value 0x30 and `b' value 0x20. The weights in filter
|
| - * may have a sum larger than 0x100, which increases coloration slightly
|
| - * but also improves contrast.
|
| - */
|
| -
|
| -
|
| - /****************************************************************************
|
| - *
|
| - * @enum:
|
| - * 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, depending on taste, your monitor, or your personal vision.
|
| - *
|
| - * 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.
|
| - *
|
| - * @since:
|
| - * 2.3.0
|
| - */
|
| - typedef enum FT_LcdFilter_
|
| - {
|
| - FT_LCD_FILTER_NONE = 0,
|
| - FT_LCD_FILTER_DEFAULT = 1,
|
| - FT_LCD_FILTER_LIGHT = 2,
|
| - FT_LCD_FILTER_LEGACY = 16,
|
| -
|
| - FT_LCD_FILTER_MAX /* do not remove */
|
| -
|
| - } FT_LcdFilter;
|
| -
|
| -
|
| - /**************************************************************************
|
| - *
|
| - * @func:
|
| - * FT_Library_SetLcdFilter
|
| - *
|
| - * @description:
|
| - * This function is used to apply color filtering to LCD decimated
|
| - * bitmaps, like the ones used when calling @FT_Render_Glyph with
|
| - * @FT_RENDER_MODE_LCD or @FT_RENDER_MODE_LCD_V.
|
| - *
|
| - * @input:
|
| - * library ::
|
| - * A handle to the target library instance.
|
| - *
|
| - * 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
|
| - * well on most LCD screens.
|
| - *
|
| - * @return:
|
| - * FreeType error code. 0~means success.
|
| - *
|
| - * @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.
|
| - *
|
| - * Due to *PATENTS* covering subpixel rendering, this function doesn't
|
| - * do anything except returning `FT_Err_Unimplemented_Feature' if the
|
| - * configuration macro FT_CONFIG_OPTION_SUBPIXEL_RENDERING is not
|
| - * defined in your build of the library, which should correspond to all
|
| - * default builds of FreeType.
|
| - *
|
| - * The filter affects glyph bitmaps rendered through @FT_Render_Glyph,
|
| - * @FT_Outline_Get_Bitmap, @FT_Load_Glyph, and @FT_Load_Char.
|
| - *
|
| - * It does _not_ affect the output of @FT_Outline_Render and
|
| - * @FT_Outline_Get_Bitmap.
|
| - *
|
| - * If this feature is activated, the dimensions of LCD glyph bitmaps are
|
| - * either larger or taller than the dimensions of the corresponding
|
| - * outline with regards to the pixel grid. For example, for
|
| - * @FT_RENDER_MODE_LCD, the filter adds up to 3~pixels to the left, and
|
| - * up to 3~pixels to the right.
|
| - *
|
| - * The bitmap offset values are adjusted correctly, so clients shouldn't
|
| - * need to modify their layout and glyph positioning code when enabling
|
| - * the filter.
|
| - *
|
| - * @since:
|
| - * 2.3.0
|
| - */
|
| - FT_EXPORT( FT_Error )
|
| - FT_Library_SetLcdFilter( FT_Library library,
|
| - FT_LcdFilter filter );
|
| -
|
| -
|
| - /**************************************************************************
|
| - *
|
| - * @func:
|
| - * FT_Library_SetLcdFilterWeights
|
| - *
|
| - * @description:
|
| - * Use this function to override the filter weights selected by
|
| - * @FT_Library_SetLcdFilter. By default, FreeType uses the quintuple
|
| - * (0x00, 0x55, 0x56, 0x55, 0x00) for FT_LCD_FILTER_LIGHT, and (0x10,
|
| - * 0x40, 0x70, 0x40, 0x10) for FT_LCD_FILTER_DEFAULT and
|
| - * FT_LCD_FILTER_LEGACY.
|
| - *
|
| - * @input:
|
| - * library ::
|
| - * A handle to the target library instance.
|
| - *
|
| - * weights ::
|
| - * A pointer to an array; the function copies the first five bytes and
|
| - * uses them to specify the filter weights.
|
| - *
|
| - * @return:
|
| - * FreeType error code. 0~means success.
|
| - *
|
| - * @note:
|
| - * Due to *PATENTS* covering subpixel rendering, this function doesn't
|
| - * do anything except returning `FT_Err_Unimplemented_Feature' if the
|
| - * configuration macro FT_CONFIG_OPTION_SUBPIXEL_RENDERING is not
|
| - * defined in your build of the library, which should correspond to all
|
| - * default builds of FreeType.
|
| - *
|
| - * This function must be called after @FT_Library_SetLcdFilter to have
|
| - * any effect.
|
| - *
|
| - * @since:
|
| - * 2.4.0
|
| - */
|
| - FT_EXPORT( FT_Error )
|
| - FT_Library_SetLcdFilterWeights( FT_Library library,
|
| - unsigned char *weights );
|
| -
|
| - /* */
|
| -
|
| -
|
| -FT_END_HEADER
|
| -
|
| -#endif /* __FT_LCD_FILTER_H__ */
|
| -
|
| -
|
| -/* END */
|
|
|