gecko-dev/gfx/thebes/gfxTextRunCache.h

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/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Foundation code.
*
* The Initial Developer of the Original Code is Mozilla Foundation.
* Portions created by the Initial Developer are Copyright (C) 2006
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Vladimir Vukicevic <vladimir@pobox.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef GFX_TEXT_RUN_CACHE_H
#define GFX_TEXT_RUN_CACHE_H
#include "gfxFont.h"
/**
* A simple textrun cache for textruns that do not carry state
* (e.g., actual or potential linebreaks) and do not need complex initialization.
* The lifetimes of these textruns are managed by the cache (they are auto-expired
* after a certain period of time).
*/
class THEBES_API gfxTextRunCache {
public:
/**
* Get a textrun for the given text, using a global cache. The textrun
* must be released via ReleaseTextRun, not deleted.
* Do not set any state in the textrun (e.g. actual or potential linebreaks).
* Flags IS_8BIT and IS_ASCII are automatically set appropriately.
* Flag IS_PERSISTENT must NOT be set unless aText is guaranteed to live
* forever.
* The string can contain any characters, invalid ones will be stripped
* properly.
*/
static gfxTextRun *MakeTextRun(const PRUnichar *aText, PRUint32 aLength,
gfxFontGroup *aFontGroup,
gfxContext *aRefContext,
PRUint32 aAppUnitsPerDevUnit,
PRUint32 aFlags);
/**
* As above, but allows a full Parameters object to be passed in.
*/
static gfxTextRun *MakeTextRun(const PRUnichar *aText, PRUint32 aLength,
gfxFontGroup *aFontGroup,
const gfxTextRunFactory::Parameters* aParams,
PRUint32 aFlags);
/**
* Get a textrun for the given text, using a global cache. The textrun
* must be released via ReleaseTextRun, not deleted.
* Do not set any state in the textrun (e.g. actual or potential linebreaks).
* Flags IS_8BIT, IS_ASCII and HAS_SURROGATES are automatically set
* appropriately.
* Flag IS_PERSISTENT must NOT be set unless aText is guaranteed to live
* forever.
* The string can contain any characters, invalid ones will be stripped
* properly.
*/
static gfxTextRun *MakeTextRun(const PRUint8 *aText, PRUint32 aLength,
gfxFontGroup *aFontGroup,
gfxContext *aRefContext,
PRUint32 aAppUnitsPerDevUnit,
PRUint32 aFlags);
/**
* Release a previously acquired textrun. Consider using AutoTextRun
* instead of calling this.
*/
static void ReleaseTextRun(gfxTextRun *aTextRun);
class AutoTextRun {
public:
AutoTextRun(gfxTextRun *aTextRun) : mTextRun(aTextRun) {}
AutoTextRun() : mTextRun(nsnull) {}
AutoTextRun& operator=(gfxTextRun *aTextRun) {
gfxTextRunCache::ReleaseTextRun(mTextRun);
mTextRun = aTextRun;
return *this;
}
~AutoTextRun() {
gfxTextRunCache::ReleaseTextRun(mTextRun);
}
gfxTextRun *get() { return mTextRun; }
gfxTextRun *operator->() { return mTextRun; }
private:
gfxTextRun *mTextRun;
};
protected:
friend class gfxPlatform;
static nsresult Init();
static void Shutdown();
};
#endif /* GFX_TEXT_RUN_CACHE_H */