cxdrawing.cpp

将OpenCV移植到DSP上

        ep_table[1] = ep_table[3] = ((((j - i) & 0x78) | 4) * slope >> 8) & 0x1ff;
        ep_table[2] = (t1 >> 8) & 0x1ff;
        ep_table[4] = ((((j - i) + 0x80) | 4) * slope >> 8) & 0x1ff;
        ep_table[5] = ((t1 + t0) >> 8) & 0x1ff;
        ep_table[6] = (t2 >> 8) & 0x1ff;
        ep_table[7] = ((t2 + t0) >> 8) & 0x1ff;
    }

    if( nch == 3 )
    {
        #define  ICV_PUT_POINT()            \
        {                                   \
            _cb = tptr[0];                  \
            _cb += ((cb - _cb)*a + 127)>> 8;\
            _cg = tptr[1];                  \
            _cg += ((cg - _cg)*a + 127)>> 8;\
            _cr = tptr[2];                  \
            _cr += ((cr - _cr)*a + 127)>> 8;\
            tptr[0] = (uchar)_cb;           \
            tptr[1] = (uchar)_cg;           \
            tptr[2] = (uchar)_cr;           \
        }
        if( ax > ay )
        {
            ptr += (pt1.x >> XY_SHIFT) * 3;

            while( ecount >= 0 )
            {
                uchar *tptr = ptr + ((pt1.y >> XY_SHIFT) - 1) * step;

                int ep_corr = ep_table[(((scount >= 2) + 1) & (scount | 2)) * 3 +
                                       (((ecount >= 2) + 1) & (ecount | 2))];
                int a, dist = (pt1.y >> (XY_SHIFT - 5)) & 31;

                a = (ep_corr * icvFilterTable[dist + 32] >> 8) & 0xff;
                ICV_PUT_POINT();
                ICV_PUT_POINT();

                tptr += step;
                a = (ep_corr * icvFilterTable[dist] >> 8) & 0xff;
                ICV_PUT_POINT();
                ICV_PUT_POINT();

                tptr += step;
                a = (ep_corr * icvFilterTable[63 - dist] >> 8) & 0xff;
                ICV_PUT_POINT();
                ICV_PUT_POINT();

                pt1.y += y_step;
                ptr += 3;
                scount++;
                ecount--;
            }
        }
        else
        {
            ptr += (pt1.y >> XY_SHIFT) * step;

            while( ecount >= 0 )
            {
                uchar *tptr = ptr + ((pt1.x >> XY_SHIFT) - 1) * 3;

                int ep_corr = ep_table[(((scount >= 2) + 1) & (scount | 2)) * 3 +
                                       (((ecount >= 2) + 1) & (ecount | 2))];
                int a, dist = (pt1.x >> (XY_SHIFT - 5)) & 31;

                a = (ep_corr * icvFilterTable[dist + 32] >> 8) & 0xff;
                ICV_PUT_POINT();
                ICV_PUT_POINT();

                tptr += 3;
                a = (ep_corr * icvFilterTable[dist] >> 8) & 0xff;
                ICV_PUT_POINT();
                ICV_PUT_POINT();

                tptr += 3;
                a = (ep_corr * icvFilterTable[63 - dist] >> 8) & 0xff;
                ICV_PUT_POINT();
                ICV_PUT_POINT();

                pt1.x += x_step;
                ptr += step;
                scount++;
                ecount--;
            }
        }
        #undef ICV_PUT_POINT
    }
    else
    {
        #define  ICV_PUT_POINT()            \
        {                                   \
            _cb = tptr[0];                  \
            _cb += ((cb - _cb)*a + 127)>> 8;\
            tptr[0] = (uchar)_cb;           \
        }

        if( ax > ay )
        {
            ptr += (pt1.x >> XY_SHIFT);

            while( ecount >= 0 )
            {
                uchar *tptr = ptr + ((pt1.y >> XY_SHIFT) - 1) * step;

                int ep_corr = ep_table[(((scount >= 2) + 1) & (scount | 2)) * 3 +
                                       (((ecount >= 2) + 1) & (ecount | 2))];
                int a, dist = (pt1.y >> (XY_SHIFT - 5)) & 31;

                a = (ep_corr * icvFilterTable[dist + 32] >> 8) & 0xff;
                ICV_PUT_POINT();
                ICV_PUT_POINT();

                tptr += step;
                a = (ep_corr * icvFilterTable[dist] >> 8) & 0xff;
                ICV_PUT_POINT();
                ICV_PUT_POINT();

                tptr += step;
                a = (ep_corr * icvFilterTable[63 - dist] >> 8) & 0xff;
                ICV_PUT_POINT();
                ICV_PUT_POINT();

                pt1.y += y_step;
                ptr++;
                scount++;
                ecount--;
            }
        }
        else
        {
            ptr += (pt1.y >> XY_SHIFT) * step;

            while( ecount >= 0 )
            {
                uchar *tptr = ptr + ((pt1.x >> XY_SHIFT) - 1);

                int ep_corr = ep_table[(((scount >= 2) + 1) & (scount | 2)) * 3 +
                                       (((ecount >= 2) + 1) & (ecount | 2))];
                int a, dist = (pt1.x >> (XY_SHIFT - 5)) & 31;

                a = (ep_corr * icvFilterTable[dist + 32] >> 8) & 0xff;
                ICV_PUT_POINT();
                ICV_PUT_POINT();

                tptr++;
                a = (ep_corr * icvFilterTable[dist] >> 8) & 0xff;
                ICV_PUT_POINT();
                ICV_PUT_POINT();

                tptr++;
                a = (ep_corr * icvFilterTable[63 - dist] >> 8) & 0xff;
                ICV_PUT_POINT();
                ICV_PUT_POINT();

                pt1.x += x_step;
                ptr += step;
                scount++;
                ecount--;
            }
        }
        #undef ICV_PUT_POINT
    }
}


static void
icvLine2( CvMat* img, CvPoint pt1, CvPoint pt2, const void* color )
{
    int dx, dy;
    int ecount;
    int ax, ay;
    int i, j;
    int x_step, y_step;
    int cb = ((uchar*)color)[0], cg = ((uchar*)color)[1], cr = ((uchar*)color)[2];
    int pix_size = CV_ELEM_SIZE( img->type );
    uchar *ptr = (uchar*)(img->data.ptr), *tptr;
    int step = img->step;
    CvSize size = cvGetMatSize( img );

    //assert( img && (nch == 1 || nch == 3) && CV_MAT_DEPTH(img->type) == CV_8U );

    pt1.x -= XY_ONE*2;
    pt1.y -= XY_ONE*2;
    pt2.x -= XY_ONE*2;
    pt2.y -= XY_ONE*2;
    ptr += img->step*2 + 2*pix_size;

    size.width = ((size.width - 5) << XY_SHIFT) + 1;
    size.height = ((size.height - 5) << XY_SHIFT) + 1;

    if( !cvClipLine( size, &pt1, &pt2 ))
        return;

    dx = pt2.x - pt1.x;
    dy = pt2.y - pt1.y;

    j = dx < 0 ? -1 : 0;
    ax = (dx ^ j) - j;
    i = dy < 0 ? -1 : 0;
    ay = (dy ^ i) - i;

    if( ax > ay )
    {
        dx = ax;
        dy = (dy ^ j) - j;
        pt1.x ^= pt2.x & j;
        pt2.x ^= pt1.x & j;
        pt1.x ^= pt2.x & j;
        pt1.y ^= pt2.y & j;
        pt2.y ^= pt1.y & j;
        pt1.y ^= pt2.y & j;

        x_step = XY_ONE;
        y_step = (int) (( dy << XY_SHIFT) / (ax | 1));
        ecount = (pt2.x - pt1.x) >> XY_SHIFT;
    }
    else
    {
        dy = ay;
        dx = (dx ^ i) - i;
        pt1.x ^= pt2.x & i;
        pt2.x ^= pt1.x & i;
        pt1.x ^= pt2.x & i;
        pt1.y ^= pt2.y & i;
        pt2.y ^= pt1.y & i;
        pt1.y ^= pt2.y & i;

        x_step = (int) (( dx << XY_SHIFT) / (ay | 1));
        y_step = XY_ONE;
        ecount = (pt2.y - pt1.y) >> XY_SHIFT;
    }

    pt1.x += (XY_ONE >> 1);
    pt1.y += (XY_ONE >> 1);

    if( pix_size == 3 )
    {
        #define  ICV_PUT_POINT()    \
        {                           \
            tptr[0] = (uchar)cb;    \
            tptr[1] = (uchar)cg;    \
            tptr[2] = (uchar)cr;    \
        }
        
        tptr = ptr + ((pt2.x + (XY_ONE >> 1))>> XY_SHIFT)*3 +
            ((pt2.y + (XY_ONE >> 1)) >> XY_SHIFT)*step;
        ICV_PUT_POINT();
        
        if( ax > ay )
        {
            ptr += (pt1.x >> XY_SHIFT) * 3;

            while( ecount >= 0 )
            {
                tptr = ptr + (pt1.y >> XY_SHIFT) * step;
                ICV_PUT_POINT();
                pt1.y += y_step;
                ptr += 3;
                ecount--;
            }
        }
        else
        {
            ptr += (pt1.y >> XY_SHIFT) * step;

            while( ecount >= 0 )
            {
                tptr = ptr + (pt1.x >> XY_SHIFT) * 3;
                ICV_PUT_POINT();
                pt1.x += x_step;
                ptr += step;
                ecount--;
            }
        }

        #undef ICV_PUT_POINT
    }
    else if( pix_size == 1 )
    {
        #define  ICV_PUT_POINT()            \
        {                                   \
            tptr[0] = (uchar)cb;            \
        }

        tptr = ptr + ((pt2.x + (XY_ONE >> 1))>> XY_SHIFT) +
            ((pt2.y + (XY_ONE >> 1)) >> XY_SHIFT)*step;
        ICV_PUT_POINT();

        if( ax > ay )
        {
            ptr += (pt1.x >> XY_SHIFT);

            while( ecount >= 0 )
            {
                tptr = ptr + (pt1.y >> XY_SHIFT) * step;
                ICV_PUT_POINT();
                pt1.y += y_step;
                ptr++;
                ecount--;
            }
        }
        else
        {
            ptr += (pt1.y >> XY_SHIFT) * step;

            while( ecount >= 0 )
            {
                tptr = ptr + (pt1.x >> XY_SHIFT);
                ICV_PUT_POINT();
                pt1.x += x_step;
                ptr += step;
                ecount--;
            }
        }
        #undef ICV_PUT_POINT
    }
    else
    {
        #define  ICV_PUT_POINT()                \
            for( j = 0; j < pix_size; j++ )     \
                tptr[j] = ((uchar*)color)[j];

        tptr = ptr + ((pt2.x + (XY_ONE >> 1))>> XY_SHIFT)*pix_size +
            ((pt2.y + (XY_ONE >> 1)) >> XY_SHIFT)*step;
        ICV_PUT_POINT();
        
        if( ax > ay )
        {
            ptr += (pt1.x >> XY_SHIFT) * pix_size;

            while( ecount >= 0 )
            {
                tptr = ptr + (pt1.y >> XY_SHIFT) * step;
                ICV_PUT_POINT();
                pt1.y += y_step;
                ptr += pix_size;
                ecount--;
            }
        }
        else
        {
            ptr += (pt1.y >> XY_SHIFT) * step;

            while( ecount >= 0 )
            {
                tptr = ptr + (pt1.x >> XY_SHIFT) * pix_size;
                ICV_PUT_POINT();
                pt1.x += x_step;
                ptr += step;
                ecount--;
            }
        }

        #undef ICV_PUT_POINT
    }
}


/****************************************************************************************\
*                   Antialiazed Elliptic Arcs via Antialiazed Lines                      *
\****************************************************************************************/

static const float icvSinTable[] =
    { 0.0000000f, 0.0174524f, 0.0348995f, 0.0523360f, 0.0697565f, 0.0871557f,
    0.1045285f, 0.1218693f, 0.1391731f, 0.1564345f, 0.1736482f, 0.1908090f,
    0.2079117f, 0.2249511f, 0.2419219f, 0.2588190f, 0.2756374f, 0.2923717f,
    0.3090170f, 0.3255682f, 0.3420201f, 0.3583679f, 0.3746066f, 0.3907311f,
    0.4067366f, 0.4226183f, 0.4383711f, 0.4539905f, 0.4694716f, 0.4848096f,
    0.5000000f, 0.5150381f, 0.5299193f, 0.5446390f, 0.5591929f, 0.5735764f,
    0.5877853f, 0.6018150f, 0.6156615f, 0.6293204f, 0.6427876f, 0.6560590f,
    0.6691306f, 0.6819984f, 0.6946584f, 0.7071068f, 0.7193398f, 0.7313537f,
    0.7431448f, 0.7547096f, 0.7660444f, 0.7771460f, 0.7880108f, 0.7986355f,
    0.8090170f, 0.8191520f, 0.8290376f, 0.8386706f, 0.8480481f, 0.8571673f,
    0.8660254f, 0.8746197f, 0.8829476f, 0.8910065f, 0.8987940f, 0.9063078f,
    0.9135455f, 0.9205049f, 0.9271839f, 0.9335804f, 0.9396926f, 0.9455186f,
    0.9510565f, 0.9563048f, 0.9612617f, 0.9659258f, 0.9702957f, 0.9743701f,
    0.9781476f, 0.9816272f, 0.9848078f, 0.9876883f, 0.9902681f, 0.9925462f,
    0.9945219f, 0.9961947f, 0.9975641f, 0.9986295f, 0.9993908f, 0.9998477f,
    1.0000000f, 0.9998477f, 0.9993908f, 0.9986295f, 0.9975641f, 0.9961947f,
    0.9945219f, 0.9925462f, 0.9902681f, 0.9876883f, 0.9848078f, 0.9816272f,
    0.9781476f, 0.9743701f, 0.9702957f, 0.9659258f, 0.9612617f, 0.9563048f,
    0.9510565f, 0.9455186f, 0.9396926f, 0.9335804f, 0.9271839f, 0.9205049f,
    0.9135455f, 0.9063078f, 0.8987940f, 0.8910065f, 0.8829476f, 0.8746197f,
    0.8660254f, 0.8571673f, 0.8480481f, 0.8386706f, 0.8290376f, 0.8191520f,
    0.8090170f, 0.7986355f, 0.7880108f, 0.7771460f, 0.7660444f, 0.7547096f,
    0.7431448f, 0.7313537f, 0.7193398f, 0.7071068f, 0.6946584f, 0.6819984f,
    0.6691306f, 0.6560590f, 0.6427876f, 0.6293204f, 0.6156615f, 0.6018150f,