+++ /dev/null
-/***************************************************************************/
-/* */
-/* autohint.h */
-/* */
-/* High-level `autohint' module-specific interface (specification). */
-/* */
-/* Copyright 1996-2001 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. */
-/* */
-/***************************************************************************/
-
-
- /*************************************************************************/
- /* */
- /* The auto-hinter is used to load and automatically hint glyphs if a */
- /* format-specific hinter isn't available. */
- /* */
- /*************************************************************************/
-
-
-#ifndef __AUTOHINT_H__
-#define __AUTOHINT_H__
-
-
- /*************************************************************************/
- /* */
- /* A small technical note regarding automatic hinting in order to */
- /* clarify this module interface. */
- /* */
- /* An automatic hinter might compute two kinds of data for a given face: */
- /* */
- /* - global hints: Usually some metrics that describe global properties */
- /* of the face. It is computed by scanning more or less */
- /* agressively the glyphs in the face, and thus can be */
- /* very slow to compute (even if the size of global */
- /* hints is really small). */
- /* */
- /* - glyph hints: These describe some important features of the glyph */
- /* outline, as well as how to align them. They are */
- /* generally much faster to compute than global hints. */
- /* */
- /* The current FreeType auto-hinter does a pretty good job while */
- /* performing fast computations for both global and glyph hints. */
- /* However, we might be interested in introducing more complex and */
- /* powerful algorithms in the future, like the one described in the John */
- /* D. Hobby paper, which unfortunately requires a lot more horsepower. */
- /* */
- /* Because a sufficiently sophisticated font management system would */
- /* typically implement an LRU cache of opened face objects to reduce */
- /* memory usage, it is a good idea to be able to avoid recomputing */
- /* global hints every time the same face is re-opened. */
- /* */
- /* We thus provide the ability to cache global hints outside of the face */
- /* object, in order to speed up font re-opening time. Of course, this */
- /* feature is purely optional, so most client programs won't even notice */
- /* it. */
- /* */
- /* I initially thought that it would be a good idea to cache the glyph */
- /* hints too. However, my general idea now is that if you really need */
- /* to cache these too, you are simply in need of a new font format, */
- /* where all this information could be stored within the font file and */
- /* decoded on the fly. */
- /* */
- /*************************************************************************/
-
-
-#include <ft2build.h>
-#include FT_FREETYPE_H
-
-
-FT_BEGIN_HEADER
-
-
- typedef struct FT_AutoHinterRec_ *FT_AutoHinter;
-
-
- /*************************************************************************/
- /* */
- /* <FuncType> */
- /* FT_AutoHinter_Get_Global_Func */
- /* */
- /* <Description> */
- /* Retrieves the global hints computed for a given face object the */
- /* resulting data is dissociated from the face and will survive a */
- /* call to FT_Done_Face(). It must be discarded through the API */
- /* FT_AutoHinter_Done_Global_Func(). */
- /* */
- /* <Input> */
- /* hinter :: A handle to the source auto-hinter. */
- /* */
- /* face :: A handle to the source face object. */
- /* */
- /* <Output> */
- /* global_hints :: A typeless pointer to the global hints. */
- /* */
- /* global_len :: The size in bytes of the global hints. */
- /* */
- typedef void
- (*FT_AutoHinter_Get_Global_Func)( FT_AutoHinter hinter,
- FT_Face face,
- void** global_hints,
- long* global_len );
-
-
- /*************************************************************************/
- /* */
- /* <FuncType> */
- /* FT_AutoHinter_Done_Global_Func */
- /* */
- /* <Description> */
- /* Discards the global hints retrieved through */
- /* FT_AutoHinter_Get_Global_Func(). This is the only way these hints */
- /* are freed from memory. */
- /* */
- /* <Input> */
- /* hinter :: A handle to the auto-hinter module. */
- /* */
- /* global :: A pointer to retrieved global hints to discard. */
- /* */
- typedef void
- (*FT_AutoHinter_Done_Global_Func)( FT_AutoHinter hinter,
- void* global );
-
-
- /*************************************************************************/
- /* */
- /* <FuncType> */
- /* FT_AutoHinter_Reset_Func */
- /* */
- /* <Description> */
- /* This function is used to recompute the global metrics in a given */
- /* font. This is useful when global font data changes (e.g. Multiple */
- /* Masters fonts where blend coordinates change). */
- /* */
- /* <Input> */
- /* hinter :: A handle to the source auto-hinter. */
- /* */
- /* face :: A handle to the face. */
- /* */
- typedef void
- (*FT_AutoHinter_Reset_Func)( FT_AutoHinter hinter,
- FT_Face face );
-
-
- /*************************************************************************/
- /* */
- /* <FuncType> */
- /* FT_AutoHinter_Load_Func */
- /* */
- /* <Description> */
- /* This function is used to load, scale, and automatically hint a */
- /* glyph from a given face. */
- /* */
- /* <Input> */
- /* face :: A handle to the face. */
- /* glyph_index :: The glyph index. */
- /* load_flags :: The load flags. */
- /* */
- /* <Note> */
- /* This function is capable of loading composite glyphs by hinting */
- /* each sub-glyph independently (which improves quality). */
- /* */
- /* It will call the font driver with FT_Load_Glyph(), with */
- /* FT_LOAD_NO_SCALE set. */
- /* */
- typedef FT_Error
- (*FT_AutoHinter_Load_Func)( FT_AutoHinter hinter,
- FT_GlyphSlot slot,
- FT_Size size,
- FT_UInt glyph_index,
- FT_ULong load_flags );
-
-
- /*************************************************************************/
- /* */
- /* <Struct> */
- /* FT_AutoHinter_Interface */
- /* */
- /* <Description> */
- /* The auto-hinter module's interface. */
- /* */
- typedef struct FT_AutoHinter_Interface
- {
- FT_AutoHinter_Reset_Func reset_face;
- FT_AutoHinter_Load_Func load_glyph;
-
- FT_AutoHinter_Get_Global_Func get_global_hints;
- FT_AutoHinter_Done_Global_Func done_global_hints;
-
- } FT_AutoHinter_Interface;
-
-
-FT_END_HEADER
-
-#endif /* __AUTOHINT_H__ */
-
-
-/* END */
projects / rrdtool.git / blobdiff