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Diffstat (limited to 'src/openvg/qvgimagepool_p.h')
| -rw-r--r-- | src/openvg/qvgimagepool_p.h | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/src/openvg/qvgimagepool_p.h b/src/openvg/qvgimagepool_p.h new file mode 100644 index 0000000..66a4998 --- /dev/null +++ b/src/openvg/qvgimagepool_p.h @@ -0,0 +1,157 @@ +/**************************************************************************** +** +** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). +** All rights reserved. +** Contact: Nokia Corporation (qt-info@nokia.com) +** +** This file is part of the QtOpenVG module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the Technology Preview License Agreement accompanying +** this package. +** +** GNU Lesser General Public License Usage +** Alternatively, this file may be used under the terms of the GNU Lesser +** General Public License version 2.1 as published by the Free Software +** Foundation and appearing in the file LICENSE.LGPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU Lesser General Public License version 2.1 requirements +** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain additional +** rights. These rights are described in the Nokia Qt LGPL Exception +** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. +** +** If you have questions regarding the use of this file, please contact +** Nokia at qt-info@nokia.com. +** +** +** +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#ifndef QVGIMAGEPOOL_P_H +#define QVGIMAGEPOOL_P_H + +// +// W A R N I N G +// ------------- +// +// This file is not part of the Qt API. It exists for the convenience +// of other Qt classes. This header file may change from version to +// version without notice, or even be removed. +// +// We mean it. +// + +#include "qvg.h" +#include <QtCore/qscopedpointer.h> + +QT_BEGIN_NAMESPACE + +class QVGPixmapData; +class QVGImagePoolPrivate; + +class Q_OPENVG_EXPORT QVGImagePool +{ +public: + QVGImagePool(); + virtual ~QVGImagePool(); + + static QVGImagePool *instance(); + + // This function can be used from system-specific graphics system + // plugins to alter the image allocation strategy. + static void setImagePool(QVGImagePool *pool); + + // Create a new VGImage from the pool with the specified parameters + // that is not associated with a pixmap. The VGImage is returned to + // the pool when releaseImage() is called. + // + // This function will call reclaimSpace() when vgCreateImage() fails. + // + // This function is typically called when allocating temporary + // VGImage's for pixmap filters. The "keepData" object will not + // be reclaimed if reclaimSpace() needs to be called. + virtual VGImage createTemporaryImage(VGImageFormat format, + VGint width, VGint height, + VGbitfield allowedQuality, + QVGPixmapData *keepData = 0); + + // Create a new VGImage with the specified parameters and associate + // it with "data". The QVGPixmapData will be notified when the + // VGImage needs to be reclaimed by the pool. + // + // This function will call reclaimSpace() when vgCreateImage() fails. + virtual VGImage createImageForPixmap(VGImageFormat format, + VGint width, VGint height, + VGbitfield allowedQuality, + QVGPixmapData *data); + + // Create a permanent VGImage with the specified parameters. + // If there is insufficient space for the vgCreateImage call, + // then this function will call reclaimSpace() and try again. + // + // The caller is responsible for calling vgDestroyImage() + // when it no longer needs the VGImage, as the image is not + // recorded in the image pool. + // + // This function is typically used for pattern brushes where + // the OpenVG engine is responsible for managing the lifetime + // of the VGImage, destroying it automatically when the brush + // is no longer in use. + virtual VGImage createPermanentImage(VGImageFormat format, + VGint width, VGint height, + VGbitfield allowedQuality); + + // Release a VGImage that is no longer required. + virtual void releaseImage(QVGPixmapData *data, VGImage image); + + // Notify the pool that a QVGPixmapData object is using + // an image again. This allows the pool to move the image + // within a least-recently-used list of QVGPixmapData objects. + virtual void useImage(QVGPixmapData *data); + + // Notify the pool that the VGImage's associated with a + // QVGPixmapData are being detached from the pool. The caller + // will become responsible for calling vgDestroyImage(). + virtual void detachImage(QVGPixmapData *data); + + // Reclaim space for an image allocation with the specified parameters. + // Returns true if space was reclaimed, or false if there is no + // further space that can be reclaimed. The "data" parameter + // indicates the pixmap that is trying to obtain space which should + // not itself be reclaimed. + virtual bool reclaimSpace(VGImageFormat format, + VGint width, VGint height, + QVGPixmapData *data); + + // Hibernate the image pool because the context is about to be + // destroyed. All VGImage's left in the pool should be released. + virtual void hibernate(); + +protected: + // Helper functions for managing the LRU list of QVGPixmapData objects. + void moveToHeadOfLRU(QVGPixmapData *data); + void removeFromLRU(QVGPixmapData *data); + QVGPixmapData *pixmapLRU(); + +private: + QScopedPointer<QVGImagePoolPrivate> d_ptr; + + Q_DECLARE_PRIVATE(QVGImagePool) + Q_DISABLE_COPY(QVGImagePool) +}; + +QT_END_NAMESPACE + +#endif |