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** contained in the Technology Preview License Agreement accompanying

** this package.

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** General Public License version 2.1 as published by the Free Software

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****************************************************************************/

#include <qmath.h>

#include "qdrawhelper_p.h"

QT_BEGIN_NAMESPACE

struct SourceOnlyAlpha

{

    inline uchar alpha(uchar src) const { return src; }

    inline quint16 bytemul(quint16 spix) const { return spix; }

};

struct SourceAndConstAlpha

{

    SourceAndConstAlpha(int a) : m_alpha256(a) {

        m_alpha255 = (m_alpha256 * 255) >> 8;

    };

    inline uchar alpha(uchar src) const { return (src * m_alpha256) >> 8; }

    inline quint16 bytemul(quint16 x) const {

        uint t = (((x & 0x07e0)*m_alpha255) >> 8) & 0x07e0;

        t |= (((x & 0xf81f)*(m_alpha255>>2)) >> 6) & 0xf81f;

        return t;

    }

    int m_alpha255;

    int m_alpha256;

};

/************************************************************************

                       RGB16 (565) format target format

 ************************************************************************/

static inline quint16 convert_argb32_to_rgb16(quint32 spix)

{

    quint32 b = spix;

    quint32 g = spix;

    b >>= 8;

    g >>= 5;

    b &= 0x0000f800;

    g &= 0x000007e0;

    spix >>= 3;

    b |= g;

    spix &= 0x0000001f;

    b |= spix;

    return b;

}

struct Blend_RGB16_on_RGB16_NoAlpha {

    inline void write(quint16 *dst, quint16 src) { *dst = src; }

};

struct Blend_RGB16_on_RGB16_ConstAlpha {

    inline Blend_RGB16_on_RGB16_ConstAlpha(quint32 alpha) {

        m_alpha = (alpha * 255) >> 8;

        m_ialpha = 255 - m_alpha;

    }

    inline void write(quint16 *dst, quint16 src) {

        *dst = BYTE_MUL_RGB16(src, m_alpha) + BYTE_MUL_RGB16(*dst, m_ialpha);

    }

    quint32 m_alpha;

    quint32 m_ialpha;

};

struct Blend_ARGB24_on_RGB16_SourceAlpha {

    inline void write(quint16 *dst, const qargb8565 &src) {

        const uint alpha = src.alpha();

        if (alpha) {

            quint16 s = src.rawValue16();

            if (alpha < 255)

                s += BYTE_MUL_RGB16(*dst, 255 - alpha);

            *dst = s;

        }

    }

};

struct Blend_ARGB24_on_RGB16_SourceAndConstAlpha {

    inline Blend_ARGB24_on_RGB16_SourceAndConstAlpha(quint32 alpha) {

        m_alpha = (alpha * 255) >> 8;

    }

    inline void write(quint16 *dst, qargb8565 src) {

        src = src.byte_mul(src.alpha(m_alpha));

        const uint alpha = src.alpha();

        if (alpha) {

            quint16 s = src.rawValue16();

            if (alpha < 255)

                s += BYTE_MUL_RGB16(*dst, 255 - alpha);

            *dst = s;

        }

    }

    quint32 m_alpha;

};

struct Blend_ARGB32_on_RGB16_SourceAlpha {

    inline void write(quint16 *dst, quint32 src) {

        const quint8 alpha = qAlpha(src);

        if(alpha) {

            quint16 s = convert_argb32_to_rgb16(src);

            if(alpha < 255)

                s += BYTE_MUL_RGB16(*dst, 255 - alpha);

            *dst = s;

        }

    }

};

struct Blend_ARGB32_on_RGB16_SourceAndConstAlpha {

    inline Blend_ARGB32_on_RGB16_SourceAndConstAlpha(quint32 alpha) {

        m_alpha = (alpha * 255) >> 8;

    }

    inline void write(quint16 *dst, quint32 src) {

        src = BYTE_MUL(src, m_alpha);

        const quint8 alpha = qAlpha(src);

        if(alpha) {

            quint16 s = convert_argb32_to_rgb16(src);

            if(alpha < 255)

                s += BYTE_MUL_RGB16(*dst, 255 - alpha);

            *dst = s;

        }

    }

    quint32 m_alpha;

};

template <typename SRC, typename T>

void qt_scale_image_16bit(uchar *destPixels, int dbpl,

                          const uchar *srcPixels, int sbpl,

                          const QRectF &targetRect,

                          const QRectF &srcRect,

                          const QRect &clip,

                          T blender)

{

    qreal sx = targetRect.width() / (qreal) srcRect.width();

    qreal sy = targetRect.height() / (qreal) srcRect.height();

    int ix = 0x00010000 / sx;

    int iy = 0x00010000 / sy;

//     qDebug() << "scale:" << endl

//              << " - target" << targetRect << endl

//              << " - source" << srcRect << endl

//              << " - clip" << clip << endl

//              << " - sx=" << sx << " sy=" << sy << " ix=" << ix << " iy=" << iy;

    int cx1 = clip.x();

    int cx2 = clip.x() + clip.width();

    int cy1 = clip.top();

    int cy2 = clip.y() + clip.height();

    int tx1 = qRound(targetRect.left());

    int tx2 = qRound(targetRect.right());

    int ty1 = qRound(targetRect.top());

    int ty2 = qRound(targetRect.bottom());

    if (tx2 < tx1)

        qSwap(tx2, tx1);

    if (ty2 < ty1)

        qSwap(ty2, ty1);

    if (tx1 < cx1)

        tx1 = cx1;

    if (tx2 >= cx2)

        tx2 = cx2;

    if (tx1 >= tx2)

        return;

    if (ty1 < cy1)

        ty1 = cy1;

    if (ty2 >= cy2)

       ty2 = cy2;

    if (ty1 >= ty2)

        return;

    int h = ty2 - ty1;

    int w = tx2 - tx1;

    const int dstx = qCeil((tx1 + 0.5 - qMin(targetRect.left(), targetRect.right())) * ix) - 1;

    const int dsty = qCeil((ty1 + 0.5 - qMin(targetRect.top(), targetRect.bottom())) * iy) - 1;

    quint32 basex = quint32((sx < 0 ? srcRect.right() : srcRect.left()) * 65536) + dstx;

    quint32 srcy = quint32((sy < 0 ? srcRect.bottom() : srcRect.top()) * 65536) + dsty;

    quint16 *dst = ((quint16 *) (destPixels + ty1 * dbpl)) + tx1;

    while (h--) {

        const SRC *src = (const SRC *) (srcPixels + (srcy >> 16) * sbpl);

        int srcx = basex;

        for (int x=0; x<w; ++x) {

            blender.write(&dst[x], src[srcx >> 16]);

            srcx += ix;

        }

        dst = (quint16 *)(((uchar *) dst) + dbpl);

        srcy += iy;

    }

}

void qt_scale_image_rgb16_on_rgb16(uchar *destPixels, int dbpl,

                                   const uchar *srcPixels, int sbpl,

                                   const QRectF &targetRect,

                                   const QRectF &sourceRect,

                                   const QRect &clip,

                                   int const_alpha)

{

#ifdef QT_DEBUG_DRAW

    printf("qt_scale_rgb16_on_rgb16: dst=(%p, %d), src=(%p, %d), target=(%d, %d), [%d x %d], src=(%d, %d) [%d x %d] alpha=%d\n",

           destPixels, dbpl, srcPixels, sbpl,

           targetRect.x(), targetRect.y(), targetRect.width(), targetRect.height(),

           sourceRect.x(), sourceRect.y(), sourceRect.width(), sourceRect.height(),

           const_alpha);

#endif

    if (const_alpha == 256) {

        Blend_RGB16_on_RGB16_NoAlpha noAlpha;

        qt_scale_image_16bit<quint16>(destPixels, dbpl, srcPixels, sbpl,

                                      targetRect, sourceRect, clip, noAlpha);

    } else {

        Blend_RGB16_on_RGB16_ConstAlpha constAlpha(const_alpha);

        qt_scale_image_16bit<quint16>(destPixels, dbpl, srcPixels, sbpl,

                                     targetRect, sourceRect, clip, constAlpha);

    }

}

void qt_scale_image_argb24_on_rgb16(uchar *destPixels, int dbpl,

                                   const uchar *srcPixels, int sbpl,

                                   const QRectF &targetRect,

                                   const QRectF &sourceRect,

                                   const QRect &clip,

                                   int const_alpha)

{

#ifdef QT_DEBUG_DRAW

    printf("qt_scale_argb24_on_rgb16: dst=(%p, %d), src=(%p, %d), target=(%d, %d), [%d x %d], src=(%d, %d) [%d x %d] alpha=%d\n",

           destPixels, dbpl, srcPixels, sbpl,

           targetRect.x(), targetRect.y(), targetRect.width(), targetRect.height(),

           sourceRect.x(), sourceRect.y(), sourceRect.width(), sourceRect.height(),

           const_alpha);

#endif

    if (const_alpha == 256) {

        Blend_ARGB24_on_RGB16_SourceAlpha noAlpha;

        qt_scale_image_16bit<qargb8565>(destPixels, dbpl, srcPixels, sbpl,

                                        targetRect, sourceRect, clip, noAlpha);

    } else {

        Blend_ARGB24_on_RGB16_SourceAndConstAlpha constAlpha(const_alpha);

        qt_scale_image_16bit<qargb8565>(destPixels, dbpl, srcPixels, sbpl,

                                        targetRect, sourceRect, clip, constAlpha);

    }

}

void qt_scale_image_argb32_on_rgb16(uchar *destPixels, int dbpl,

                                    const uchar *srcPixels, int sbpl,

                                    const QRectF &targetRect,

                                    const QRectF &sourceRect,

                                    const QRect &clip,

                                    int const_alpha)

{

#ifdef QT_DEBUG_DRAW

    printf("qt_scale_argb32_on_rgb16: dst=(%p, %d), src=(%p, %d), target=(%d, %d), [%d x %d], src=(%d, %d) [%d x %d] alpha=%d\n",

           destPixels, dbpl, srcPixels, sbpl,

           targetRect.x(), targetRect.y(), targetRect.width(), targetRect.height(),

           sourceRect.x(), sourceRect.y(), sourceRect.width(), sourceRect.height(),

           const_alpha);

#endif

    if (const_alpha == 256) {

        Blend_ARGB32_on_RGB16_SourceAlpha noAlpha;

        qt_scale_image_16bit<quint32>(destPixels, dbpl, srcPixels, sbpl,

                                      targetRect, sourceRect, clip, noAlpha);

    } else {

        Blend_ARGB32_on_RGB16_SourceAndConstAlpha constAlpha(const_alpha);

        qt_scale_image_16bit<quint32>(destPixels, dbpl, srcPixels, sbpl,

                                     targetRect, sourceRect, clip, constAlpha);

    }

}

static void qt_blend_rgb16_on_rgb16(uchar *dst, int dbpl,

                                    const uchar *src, int sbpl,

                                    int w, int h,

                                    int const_alpha)

{

#ifdef QT_DEBUG_DRAW

    printf("qt_blend_rgb16_on_rgb16: dst=(%p, %d), src=(%p, %d), dim=(%d, %d) alpha=%d\n",

           dst, dbpl, src, sbpl, w, h, const_alpha);

#endif

    if (const_alpha == 256) {

        if (w <= 64) {

            while (h--) {

                QT_MEMCPY_USHORT(dst, src, w);

                dst += dbpl;

                src += sbpl;

            }

        } else {

            int length = w << 1;

            while (h--) {

                memcpy(dst, src, length);

                dst += dbpl;

                src += sbpl;

            }

        }

    } else if (const_alpha != 0) {

        SourceAndConstAlpha alpha(const_alpha); // expects the 0-256 range

        quint16 *d = (quint16 *) dst;

        const quint16 *s = (const quint16 *) src;

        quint8 a = (255 * const_alpha) >> 8;

        quint8 ia = 255 - a;

        while (h--) {

            for (int x=0; x<w; ++x) {

                d[x] = BYTE_MUL_RGB16(s[x], a) + BYTE_MUL_RGB16(d[x], ia);

            }

            d = (quint16 *)(((uchar *) d) + dbpl);

            s = (const quint16 *)(((const uchar *) s) + sbpl);

        }

    }

}

template <typename T> void qt_blend_argb24_on_rgb16(uchar *destPixels, int dbpl,

                                                    const uchar *srcPixels, int sbpl,

                                                    int w, int h, const T &alphaFunc)

{

    int srcOffset = w*3;

    int dstJPL = dbpl / 2;

    quint16 *dst = (quint16 *) destPixels;

    int dstExtraStride = dstJPL - w;

    for (int y=0; y<h; ++y) {

        const uchar *src = srcPixels + y * sbpl;

        const uchar *srcEnd = src + srcOffset;

        while (src < srcEnd) {

#if defined(QT_ARCH_ARM) || defined(QT_ARCH_POWERPC) || defined(QT_ARCH_SH) || defined(QT_ARCH_AVR32) || (defined(QT_ARCH_WINDOWSCE) && !defined(_X86_)) || (defined(QT_ARCH_SPARC) && defined(Q_CC_GNU))

            // non-16-bit aligned memory access is not possible on PowerPC,

            // ARM <v6 (QT_ARCH_ARMV6) & SH & AVR32 & SPARC w/GCC

            quint16 spix = (quint16(src[2])<<8) + src[1];

#else

            quint16 spix = *(quint16 *) (src + 1);

#endif

            uchar alpha = alphaFunc.alpha(*src);

            if (alpha == 255) {

                *dst = spix;

            } else if (alpha != 0) {

                quint16 dpix = *dst;

                quint32 sia = 255 - alpha;

                quint16 dr = (dpix & 0x0000f800);

                quint16 dg = (dpix & 0x000007e0);

                quint16 db = (dpix & 0x0000001f);

                quint32 siar = dr * sia;

                quint32 siag = dg * sia;

                quint32 siab = db * sia;

                quint32 rr = ((siar + (siar>>8) + (0x80 <<  8)) >> 8) & 0xf800;

                quint32 rg = ((siag + (siag>>8) + (0x80 <<  3)) >> 8) & 0x07e0;

                quint32 rb = ((siab + (siab>>8) + (0x80 >>  3)) >> 8) & 0x001f;

                *dst = alphaFunc.bytemul(spix) + rr + rg + rb;

            }

            ++dst;

            src += 3;

        }

        dst += dstExtraStride;

    }

}

static void qt_blend_argb24_on_rgb16(uchar *destPixels, int dbpl,

                                     const uchar *srcPixels, int sbpl,

                                     int w, int h,

                                     int const_alpha)

{

#ifdef QT_DEBUG_DRAW

    printf("qt_blend_argb24_on_rgb16: dst=(%p, %d), src=(%p, %d), dim=(%d, %d) alpha=%d\n",

           destPixels, dbpl, srcPixels, sbpl, w, h, const_alpha);

#endif

    if (const_alpha != 256) {

        SourceAndConstAlpha alphaFunc(const_alpha);

        qt_blend_argb24_on_rgb16(destPixels, dbpl, srcPixels, sbpl, w, h, alphaFunc);

    } else {

        SourceOnlyAlpha alphaFunc;

        qt_blend_argb24_on_rgb16(destPixels, dbpl, srcPixels, sbpl, w, h, alphaFunc);

    }

}

static void qt_blend_argb32_on_rgb16_const_alpha(uchar *destPixels, int dbpl,

                                                 const uchar *srcPixels, int sbpl,

                                                 int w, int h,

                                                 int const_alpha)

{

    quint16 *dst = (quint16 *) destPixels;

    const quint32 *src = (const quint32 *) srcPixels;

    const_alpha = (const_alpha * 255) >> 8;

    for (int y=0; y<h; ++y) {

        for (int i = 0; i < w; ++i) {

            uint s = src[i];

            s = BYTE_MUL(s, const_alpha);

            int alpha = qAlpha(s);

            s = convert_argb32_to_rgb16(s);

            s += BYTE_MUL_RGB16(dst[i], 255 - alpha);

            dst[i] = s;

        }

        dst = (quint16 *)(((uchar *) dst) + dbpl);

        src = (const quint32 *)(((const uchar *) src) + sbpl);

    }

}

static void qt_blend_argb32_on_rgb16(uchar *destPixels, int dbpl,

                                     const uchar *srcPixels, int sbpl,

                                     int w, int h,

                                     int const_alpha)

{

    if (const_alpha != 256) {

        qt_blend_argb32_on_rgb16_const_alpha(destPixels, dbpl, srcPixels, sbpl, w, h, const_alpha);

        return;

    }

    quint16 *dst = (quint16 *) destPixels;

    quint32 *src = (quint32 *) srcPixels;

    for (int y=0; y<h; ++y) {

        for (int x=0; x<w; ++x) {

            quint32 spix = src[x];

            quint32 alpha = spix >> 24;

            if (alpha == 255) {

                dst[x] = convert_argb32_to_rgb16(spix);

            } else if (alpha != 0) {

                quint32 dpix = dst[x];

                quint32 sia = 255 - alpha;

                quint32 sr = (spix >> 8) & 0xf800;

                quint32 sg = (spix >> 5) & 0x07e0;

                quint32 sb = (spix >> 3) & 0x001f;

                quint32 dr = (dpix & 0x0000f800);

                quint32 dg = (dpix & 0x000007e0);

                quint32 db = (dpix & 0x0000001f);

                quint32 siar = dr * sia;

                quint32 siag = dg * sia;

                quint32 siab = db * sia;

                quint32 rr = sr + ((siar + (siar>>8) + (0x80 << 8)) >> 8);

                quint32 rg = sg + ((siag + (siag>>8) + (0x80 << 3)) >> 8);

                quint32 rb = sb + ((siab + (siab>>8) + (0x80 >> 3)) >> 8);

                dst[x] = (rr & 0xf800)

                         | (rg & 0x07e0)

                         | (rb);

            }

        }

        dst = (quint16 *) (((uchar *) dst) + dbpl);

        src = (quint32 *) (((uchar *) src) + sbpl);

    }

}

static void qt_blend_rgb32_on_rgb16(uchar *destPixels, int dbpl,

                                    const uchar *srcPixels, int sbpl,

                                    int w, int h,

                                    int const_alpha)

{

#ifdef QT_DEBUG_DRAW

    printf("qt_blend_rgb32_on_rgb16: dst=(%p, %d), src=(%p, %d), dim=(%d, %d) alpha=%d\n",

           destPixels, dbpl, srcPixels, sbpl, w, h, const_alpha);

#endif

    if (const_alpha != 256) {

        qt_blend_argb32_on_rgb16(destPixels, dbpl, srcPixels, sbpl, w, h, const_alpha);

        return;

    }

    const quint32 *src = (const quint32 *) srcPixels;