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Diffstat (limited to 'include/vcl/scopedbitmapaccess.hxx')
-rw-r--r-- | include/vcl/scopedbitmapaccess.hxx | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/include/vcl/scopedbitmapaccess.hxx b/include/vcl/scopedbitmapaccess.hxx new file mode 100644 index 000000000000..834f827e14aa --- /dev/null +++ b/include/vcl/scopedbitmapaccess.hxx @@ -0,0 +1,94 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * This file is part of the LibreOffice project. + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. + * + * This file incorporates work covered by the following license notice: + * + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed + * with this work for additional information regarding copyright + * ownership. The ASF licenses this file to you under the Apache + * License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0 . + */ + +#ifndef VCL_SCOPEDBITMAPACCESS_HXX_INCLUDED +#define VCL_SCOPEDBITMAPACCESS_HXX_INCLUDED + +namespace vcl +{ + +/** This template handles BitmapAccess the RAII way. + + Please don't use directly, but through the ready-made typedefs + ScopedReadAccess and ScopedWriteAccess in classes Bitmap and + AlphaMask. + + Use as follows: + Bitmap aBitmap; + Bitmap::ScopedReadAccess pReadAccess( aBitmap ); + pReadAccess->SetPixel()... + + Bitmap aBitmap2; + Bitmap::ScopedWriteAccess pWriteAccess( bCond ? aBitmap2.AcquireWriteAccess() : 0, aBitmap2 ); + if ( pWriteAccess )... + + @attention for practical reasons, ScopedBitmapAccess stores a + reference to the provided bitmap, thus, make sure that the bitmap + specified at construction time lives at least as long as the + ScopedBitmapAccess. + */ +template < class Access, class Bitmap, Access* (Bitmap::* Acquire)() > class ScopedBitmapAccess +{ + typedef ScopedBitmapAccess< Access, Bitmap, Acquire > self_type; + typedef bool (self_type::* unspecified_bool_type)() const; + +public: + explicit ScopedBitmapAccess( Bitmap& rBitmap ) : + mpAccess( 0 ), + mrBitmap( rBitmap ) + { + mpAccess = (mrBitmap.*Acquire)(); + } + + ScopedBitmapAccess( Access* pAccess, Bitmap& rBitmap ) : + mpAccess( pAccess ), + mrBitmap( rBitmap ) + { + } + + ~ScopedBitmapAccess() + { + mrBitmap.ReleaseAccess( mpAccess ); + } + + bool operator!() const { return !mpAccess; } + operator unspecified_bool_type() const + { + return mpAccess ? &self_type::operator! : 0; + } + + Access* get() { return mpAccess; } + const Access* get() const { return mpAccess; } + + Access* operator->() { return mpAccess; } + const Access* operator->() const { return mpAccess; } + + Access& operator*() { return *mpAccess; } + const Access& operator*() const { return *mpAccess; } + +private: + Access* mpAccess; + Bitmap& mrBitmap; +}; + +} + +#endif // VCL_SCOPEDBITMAPACCESS_HXX_INCLUDED + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |