/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd.
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****************************************************************************/

#ifndef QGLCOLORMAP_H
#define QGLCOLORMAP_H

#include <QtGui/qcolor.h>
#include <QtCore/qvector.h>
#include <QtOpenGL/qtopenglglobal.h>

QT_BEGIN_NAMESPACE


class Q_OPENGL_EXPORT QGLColormap
{
public:
    QGLColormap();
    QGLColormap(const QGLColormap &);
    ~QGLColormap();

    QGLColormap &operator=(const QGLColormap &);

    bool   isEmpty() const;
    int    size() const;
    void   detach();

    void   setEntries(int count, const QRgb * colors, int base = 0);
    void   setEntry(int idx, QRgb color);
    void   setEntry(int idx, const QColor & color);
    QRgb   entryRgb(int idx) const;
    QColor entryColor(int idx) const;
    int    find(QRgb color) const;
    int    findNearest(QRgb color) const;

protected:
    Qt::HANDLE handle() { return d ? d->cmapHandle : 0; }
    void setHandle(Qt::HANDLE ahandle) { d->cmapHandle = ahandle; }

private:
    struct QGLColormapData {
        QBasicAtomicInt ref;
        QVector<QRgb> *cells;
        Qt::HANDLE cmapHandle;
    };

    QGLColormapData *d;
    static struct QGLColormapData shared_null;
    static void cleanup(QGLColormapData *x);
    void detach_helper();

    friend class QGLWidget;
    friend class QGLWidgetPrivate;
};

inline void QGLColormap::detach()
{
    if (d->ref.load() != 1)
        detach_helper();
}

QT_END_NAMESPACE

#endif // QGLCOLORMAP_H
