diff options
Diffstat (limited to 'include/ftautoh.h')
| -rw-r--r-- | include/ftautoh.h | 74 |
1 files changed, 61 insertions, 13 deletions
diff --git a/include/ftautoh.h b/include/ftautoh.h index 936791e..cf7b76f 100644 --- a/include/ftautoh.h +++ b/include/ftautoh.h @@ -4,7 +4,7 @@ /* */ /* FreeType API for controlling the auto-hinter (specification only). */ /* */ -/* Copyright 2012, 2013 by */ +/* Copyright 2012-2015 by */ /* David Turner, Robert Wilhelm, and Werner Lemberg. */ /* */ /* This file is part of the FreeType project, and may only be used, */ @@ -245,12 +245,12 @@ FT_BEGIN_HEADER * The data exchange structure for the @glyph-to-script-map property. * */ - typedef struct FT_Prop_GlyphToScriptMap_ - { - FT_Face face; - FT_Byte* map; + typedef struct FT_Prop_GlyphToScriptMap_ + { + FT_Face face; + FT_Byte* map; - } FT_Prop_GlyphToScriptMap; + } FT_Prop_GlyphToScriptMap; /************************************************************************** @@ -300,7 +300,7 @@ FT_BEGIN_HEADER * @description: * *Experimental* *only* * - * If Freetype gets compiled with FT_CONFIG_OPTION_USE_HARFBUZZ to make + * If FreeType gets compiled with FT_CONFIG_OPTION_USE_HARFBUZZ to make * the HarfBuzz library access OpenType features for getting better * glyph coverages, this property sets the (auto-fitter) script to be * used for the default (OpenType) script data of a font's GSUB table. @@ -384,15 +384,63 @@ FT_BEGIN_HEADER * The data exchange structure for the @increase-x-height property. * */ - typedef struct FT_Prop_IncreaseXHeight_ - { - FT_Face face; - FT_UInt limit; + typedef struct FT_Prop_IncreaseXHeight_ + { + FT_Face face; + FT_UInt limit; - } FT_Prop_IncreaseXHeight; + } FT_Prop_IncreaseXHeight; - /* */ + /************************************************************************** + * + * @property: + * warping + * + * @description: + * *Experimental* *only* + * + * If FreeType gets compiled with option AF_CONFIG_OPTION_USE_WARPER to + * activate the warp hinting code in the auto-hinter, this property + * switches warping on and off. + * + * Warping only works in `light' auto-hinting mode. The idea of the + * code is to slightly scale and shift a glyph along the non-hinted + * dimension (which is usually the horizontal axis) so that as much of + * its segments are aligned (more or less) to the grid. To find out a + * glyph's optimal scaling and shifting value, various parameter + * combinations are tried and scored. + * + * By default, warping is off. The example below shows how to switch on + * warping (omitting the error handling). + * + * { + * FT_Library library; + * FT_Bool warping = 1; + * + * + * FT_Init_FreeType( &library ); + * + * FT_Property_Set( library, "autofitter", + * "warping", &warping ); + * } + * + * @note: + * This property can be used with @FT_Property_Get also. + * + * The warping code can also change advance widths. Have a look at the + * `lsb_delta' and `rsb_delta' fields in the @FT_GlyphSlotRec structure + * for details on improving inter-glyph distances while rendering. + * + * Since warping is a global property of the auto-hinter it is best to + * change its value before rendering any face. Otherwise, you should + * reload all faces that get auto-hinted in `light' hinting mode. + * + */ + + + /* */ + FT_END_HEADER |