gfx/thebes/public/gfxTextRunWordCache.h

   1 /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
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   6  * 1.1 (the "License"); you may not use this file except in compliance with
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  15  * The Original Code is Mozilla Foundation code.
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  17  * The Initial Developer of the Original Code is Mozilla Foundation.
  18  * Portions created by the Initial Developer are Copyright (C) 2006
  19  * the Initial Developer. All Rights Reserved.
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  21  * Contributor(s):
  22  *   Vladimir Vukicevic <vladimir@pobox.com>
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  24  * Alternatively, the contents of this file may be used under the terms of
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  36  * ***** END LICENSE BLOCK ***** */
  37
  38 #ifndef GFX_TEXT_RUN_WORD_CACHE_H
  39 #define GFX_TEXT_RUN_WORD_CACHE_H
  40
  41 #include "gfxFont.h"
  42
  43 /**
  44  * Cache individual "words" (strings delimited by white-space or white-space-like
  45  * characters that don't involve kerning or ligatures) in textruns.
  46   */
  47 class THEBES_API gfxTextRunWordCache {
  48 public:
  49     enum {
  50       TEXT_IN_CACHE = 0x10000000,
  51       /**
  52        * When set, the previous character for this textrun was an Arabic
  53        * character.  This is used for the context detection necessary for
  54        * bidi.numeral implementation.
  55        */
  56       TEXT_INCOMING_ARABICCHAR = 0x10000000
  57     };
  58
  59     /**
  60      * Create a textrun using cached words.
  61      * Invalid characters (see gfxFontGroup::IsInvalidChar) will be automatically
  62      * treated as invisible missing.
  63      * @param aFlags the flags TEXT_IS_ASCII and TEXT_HAS_SURROGATES must be set
  64      * by the caller, if applicable; TEXT_IN_CACHE is added if we
  65      * have a reference to the textrun in the cache and RemoveTextRun must
  66      * be called when the textrun dies.
  67      */
  68     static gfxTextRun *MakeTextRun(const PRUnichar *aText, PRUint32 aLength,
  69                                    gfxFontGroup *aFontGroup,
  70                                    const gfxFontGroup::Parameters *aParams,
  71                                    PRUint32 aFlags);
  72     /**
  73      * Create a textrun using cached words.
  74      * Invalid characters (see gfxFontGroup::IsInvalidChar) will be automatically
  75      * treated as invisible missing.
  76      * @param aFlags the flags TEXT_IS_ASCII and TEXT_HAS_SURROGATES must be set
  77      * by the caller, if applicable; TEXT_IN_CACHE is added if we
  78      * have a reference to the textrun in the cache and RemoveTextRun must
  79      * be called when the textrun dies.
  80      */
  81     static gfxTextRun *MakeTextRun(const PRUint8 *aText, PRUint32 aLength,
  82                                    gfxFontGroup *aFontGroup,
  83                                    const gfxFontGroup::Parameters *aParams,
  84                                    PRUint32 aFlags);
  85
  86     /**
  87      * Remove a textrun from the cache. This must be called before aTextRun
  88      * is deleted! The text in the textrun must still be valid.
  89      */
  90     static void RemoveTextRun(gfxTextRun *aTextRun);
  91
  92 protected:
  93     friend class gfxPlatform;
  94
  95     static nsresult Init();
  96     static void Shutdown();
  97 };
  98
  99 #endif /* GFX_TEXT_RUN_WORD_CACHE_H */