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#ifndef QEGLPLATFORMCURSOR_H
#define QEGLPLATFORMCURSOR_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists purely as an
// implementation detail.  This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//

#include <qpa/qplatformcursor.h>
#include <qpa/qplatformscreen.h>
#include <QtGui/QOpenGLFunctions>

QT_BEGIN_NAMESPACE

class QOpenGLShaderProgram;
class QDeviceDiscovery;
class QEGLPlatformCursor;

class QEGLPlatformCursorDeviceListener : public QObject
{
    Q_OBJECT

public:
    QEGLPlatformCursorDeviceListener(QDeviceDiscovery *dd, QEGLPlatformCursor *cursor);
    bool hasMouse() const;

private slots:
    void onDeviceAdded();
    void onDeviceRemoved();

private:
    QEGLPlatformCursor *m_cursor;
    int m_mouseCount;
};

class QEGLPlatformCursorUpdater : public QObject
{
    Q_OBJECT

public:
    QEGLPlatformCursorUpdater(QPlatformScreen *screen)
        : m_screen(screen), m_active(false) { }

    void scheduleUpdate(const QPoint &pos, const QRegion &rgn);

private slots:
    void update(const QPoint &pos, const QRegion &rgn);

private:
    QPlatformScreen *m_screen;
    bool m_active;
};

class QEGLPlatformCursor : public QPlatformCursor, protected QOpenGLFunctions
{
    Q_OBJECT
public:
    QEGLPlatformCursor(QPlatformScreen *screen);
    ~QEGLPlatformCursor();

#ifndef QT_NO_CURSOR
    void changeCursor(QCursor *cursor, QWindow *widget) Q_DECL_OVERRIDE;
#endif
    void pointerEvent(const QMouseEvent &event) Q_DECL_OVERRIDE;
    QPoint pos() const Q_DECL_OVERRIDE;
    void setPos(const QPoint &pos) Q_DECL_OVERRIDE;

    QRect cursorRect() const;
    void paintOnScreen();
    void resetResources();

    void setMouseDeviceDiscovery(QDeviceDiscovery *dd);
    void updateMouseStatus();

private:
#ifndef QT_NO_CURSOR
    bool setCurrentCursor(QCursor *cursor);
#endif
    void draw(const QRectF &rect);
    void update(const QRegion &region);
    void createShaderPrograms();
    void createCursorTexture(uint *texture, const QImage &image);
    void initCursorAtlas();

    // current cursor information
    struct Cursor {
        Cursor() : texture(0), shape(Qt::BlankCursor), customCursorTexture(0), customCursorPending(false) { }
        uint texture; // a texture from 'image' or the atlas
        Qt::CursorShape shape;
        QRectF textureRect; // normalized rect inside texture
        QSize size; // size of the cursor
        QPoint hotSpot;
        QImage customCursorImage;
        QPoint pos; // current cursor position
        uint customCursorTexture;
        bool customCursorPending;
    } m_cursor;

    // cursor atlas information
    struct CursorAtlas {
        CursorAtlas() : cursorsPerRow(0), texture(0), cursorWidth(0), cursorHeight(0) { }
        int cursorsPerRow;
        uint texture;
        int width, height; // width and height of the atlas
        int cursorWidth, cursorHeight; // width and height of cursors inside the atlas
        QList<QPoint> hotSpots;
        QImage image; // valid until it's uploaded
    } m_cursorAtlas;

    bool m_visible;
    QPlatformScreen *m_screen;
    QOpenGLShaderProgram *m_program;
    int m_vertexCoordEntry;
    int m_textureCoordEntry;
    int m_textureEntry;
    QEGLPlatformCursorDeviceListener *m_deviceListener;
    QEGLPlatformCursorUpdater m_updater;
};

QT_END_NAMESPACE

#endif // QEGLPLATFORMCURSOR_H