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diff --git a/src/declarative/scenegraph/qsgdistancefieldglyphcache_p.h b/src/declarative/scenegraph/qsgdistancefieldglyphcache_p.h
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+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtDeclarative 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 DISTANCEFIELDGLYPHCACHE_H
+#define DISTANCEFIELDGLYPHCACHE_H
+
+#include <qgl.h>
+#include <qrawfont.h>
+#include <private/qgl_p.h>
+#include <private/qfont_p.h>
+#include <private/qfontengine_p.h>
+
+QT_BEGIN_NAMESPACE
+
+class QGLShaderProgram;
+
+class Q_DECLARATIVE_EXPORT QSGDistanceFieldGlyphCache : public QObject
+{
+    Q_OBJECT
+public:
+    ~QSGDistanceFieldGlyphCache();
+
+    static QSGDistanceFieldGlyphCache *get(const QGLContext *ctx, const QRawFont &font);
+
+    struct Metrics {
+        qreal width;
+        qreal height;
+        qreal baselineX;
+        qreal baselineY;
+
+        bool isNull() const { return width == 0 || height == 0; }
+    };
+    Metrics glyphMetrics(glyph_t glyph);
+
+    struct TexCoord {
+        qreal x;
+        qreal y;
+        qreal width;
+        qreal height;
+        qreal xMargin;
+        qreal yMargin;
+
+        TexCoord() : x(0), y(0), width(0), height(0), xMargin(0), yMargin(0) { }
+
+        bool isNull() const { return width == 0 || height == 0; }
+    };
+    TexCoord glyphTexCoord(glyph_t glyph);
+
+    GLuint texture();
+    QSize textureSize() const;
+    int maxTextureSize() const;
+    qreal fontScale() const;
+    int distanceFieldRadius() const;
+    QImage renderDistanceFieldGlyph(glyph_t glyph) const;
+
+    int glyphCount() const;
+
+    void populate(int count, const glyph_t *glyphs);
+    void derefGlyphs(int count, const glyph_t *glyphs);
+    void updateCache();
+
+    bool cacheIsFull() const { return m_textureData->currY >= maxTextureSize(); }
+
+    bool useWorkaroundBrokenFBOReadback() const;
+
+    static bool distanceFieldEnabled();
+
+private Q_SLOTS:
+    void onContextDestroyed(const QGLContext *context);
+
+private:
+    QSGDistanceFieldGlyphCache(const QGLContext *c, const QRawFont &font);
+
+    void createTexture(int width, int height);
+    void resizeTexture(int width, int height);
+
+    static QHash<QString, QSGDistanceFieldGlyphCache *> m_caches;
+
+    QRawFont m_font;
+    QRawFont m_referenceFont;
+
+    QString m_distanceFieldKey;
+    int m_glyphCount;
+    QHash<glyph_t, Metrics> m_metrics;
+    mutable int m_maxTextureSize;
+
+    struct DistanceFieldTextureData {
+        GLuint texture;
+        GLuint fbo;
+        QSize size;
+        QHash<glyph_t, TexCoord> texCoords;
+        QSet<glyph_t> pendingGlyphs;
+        QHash<glyph_t, quint32> glyphRefCount;
+        QSet<glyph_t> unusedGlyphs;
+        int currX;
+        int currY;
+        QImage image;
+        bool doubleGlyphResolution;
+
+        DistanceFieldTextureData(const QGLContext *)
+            : texture(0)
+            , fbo(0)
+            , currX(0)
+            , currY(0)
+            , doubleGlyphResolution(false)
+        { }
+    };
+    DistanceFieldTextureData *textureData();
+    DistanceFieldTextureData *m_textureData;
+    static QHash<QString, QGLContextGroupResource<DistanceFieldTextureData> > m_textures_data;
+
+    const QGLContext *ctx;
+    QGLShaderProgram *m_blitProgram;
+    GLfloat m_vertexCoordinateArray[8];
+    GLfloat m_textureCoordinateArray[8];
+
+};
+
+QT_END_NAMESPACE
+
+#endif // DISTANCEFIELDGLYPHCACHE_H