libmng_pixels.c

奇趣公司比较新的qt/emd版本

                            (mng_uint32)(AB) / (mng_uint32)(AC));                \
       (RC) = (mng_uint16)((S * (mng_uint32)(RT) +                               \
                            T * (mng_uint32)(RB) + (mng_uint32)32767) >> 16);    \
       (GC) = (mng_uint16)((S * (mng_uint32)(GT) +                               \
                            T * (mng_uint32)(GB) + (mng_uint32)32767) >> 16);    \
       (BC) = (mng_uint16)((S * (mng_uint32)(BT) +                               \
                            T * (mng_uint32)(BB) + (mng_uint32)32767) >> 16); }

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

/* note a good optimizing compiler will optimize this */
#define DIV255B8(x) (mng_uint8)(((x) + 127) / 255)
#define DIV255B16(x) (mng_uint16)(((x) + 32767) / 65535)

/* ************************************************************************** */
/* *                                                                        * */
/* * Progressive display check - checks to see if progressive display is    * */
/* * in order & indicates so                                                * */
/* *                                                                        * */
/* * The routine is called after a call to one of the display_xxx routines  * */
/* * if appropriate                                                         * */
/* *                                                                        * */
/* * The refresh is warrented in the read_chunk routine (mng_read.c)        * */
/* * and only during read&display processing, since there's not much point  * */
/* * doing it from memory!                                                  * */
/* *                                                                        * */
/* ************************************************************************** */

mng_retcode mng_display_progressive_check (mng_datap pData)
{
  if ((pData->bDoProgressive) &&       /* need progressive display? */
      ((pData->eImagetype != mng_it_mng) || (pData->iDataheight > 300)) &&
      (pData->iDestb - pData->iDestt > 50) && (!pData->pCurraniobj))
  {
    mng_int32 iC = pData->iRow + pData->iDestt - pData->iSourcet;

    if (iC % 20 == 0)                  /* every 20th line */
      pData->bNeedrefresh = MNG_TRUE;

  }

  return MNG_NOERROR;
}

/* ************************************************************************** */
/* *                                                                        * */
/* * Display routines - convert rowdata (which is already color-corrected)  * */
/* * to the output canvas, respecting the opacity information               * */
/* *                                                                        * */
/* ************************************************************************** */

MNG_LOCAL void check_update_region (mng_datap pData)
{                                      /* determine actual canvas row */
  mng_int32 iRow = pData->iRow + pData->iDestt - pData->iSourcet;
                                       /* check for change in update-region */
  if ((pData->iDestl < (mng_int32)pData->iUpdateleft) || (pData->iUpdateright == 0))
    pData->iUpdateleft   = pData->iDestl;

  if (pData->iDestr > (mng_int32)pData->iUpdateright)
    pData->iUpdateright  = pData->iDestr;

  if ((iRow < (mng_int32)pData->iUpdatetop) || (pData->iUpdatebottom == 0))
    pData->iUpdatetop    = iRow;

  if (iRow+1 > (mng_int32)pData->iUpdatebottom)
    pData->iUpdatebottom = iRow+1;

  return;
}

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

#ifndef MNG_SKIPCANVAS_RGB8
mng_retcode mng_display_rgb8 (mng_datap pData)
{
  mng_uint8p pScanline;
  mng_uint8p pDataline;
  mng_int32  iX;
#ifndef MNG_NO_16BIT_SUPPORT
  mng_uint16 iA16;
#ifndef MNG_OPTIMIZE_FOOTPRINT_COMPOSE
  mng_uint16 iFGr16, iFGg16, iFGb16;
  mng_uint16 iBGr16, iBGg16, iBGb16;
#else
  mng_uint16 iFGg16;
  mng_uint16 iBGg16;
#endif
#endif
  mng_uint8  iA8;

#ifdef MNG_SUPPORT_TRACE
  MNG_TRACE (pData, MNG_FN_DISPLAY_RGB8, MNG_LC_START);
#endif
                                       /* viewable row ? */
  if ((pData->iRow >= pData->iSourcet) && (pData->iRow < pData->iSourceb))
  {                                    /* address destination row */
    pScanline = (mng_uint8p)pData->fGetcanvasline (((mng_handle)pData),
                                                   pData->iRow + pData->iDestt -
                                                   pData->iSourcet);
                                       /* adjust destination row starting-point */
    pScanline = pScanline + (pData->iCol * 3) + (pData->iDestl * 3);
    pDataline = pData->pRGBArow;       /* address source row */

#ifndef MNG_NO_16BIT_SUPPORT
    if (pData->bIsRGBA16)              /* adjust source row starting-point */
      pDataline = pDataline + ((pData->iSourcel / pData->iColinc) << 3);
    else
#endif
      pDataline = pDataline + ((pData->iSourcel / pData->iColinc) << 2);

    if (pData->bIsOpaque)              /* forget about transparency ? */
    {
#ifndef MNG_NO_16BIT_SUPPORT
      if (pData->bIsRGBA16)            /* 16-bit input row ? */
      {
        for (iX = pData->iSourcel + pData->iCol; iX < pData->iSourcer; iX += pData->iColinc)
        {                              /* scale down by dropping the LSB */
          *pScanline     = *pDataline;
          *(pScanline+1) = *(pDataline+2);
          *(pScanline+2) = *(pDataline+4);

          pScanline += (pData->iColinc * 3);
          pDataline += 8;
        }
      }
      else
#endif
      {
        for (iX = pData->iSourcel + pData->iCol; iX < pData->iSourcer; iX += pData->iColinc)
        {                              /* copy the values */
          *pScanline     = *pDataline;
          *(pScanline+1) = *(pDataline+1);
          *(pScanline+2) = *(pDataline+2);

          pScanline += (pData->iColinc * 3);
          pDataline += 4;
        }
      }
    }
    else
    {
#ifndef MNG_NO_16BIT_SUPPORT
      if (pData->bIsRGBA16)            /* 16-bit input row ? */
      {
        for (iX = pData->iSourcel + pData->iCol; iX < pData->iSourcer; iX += pData->iColinc)
        {
          iA16 = mng_get_uint16 (pDataline+6);

          if (iA16)                    /* any opacity at all ? */
          {
            if (iA16 == 0xFFFF)        /* fully opaque ? */
            {                          /* scale down by dropping the LSB */
              *pScanline     = *pDataline;
              *(pScanline+1) = *(pDataline+2);
              *(pScanline+2) = *(pDataline+4);
            }
            else
            {                          /* get the proper values */
#ifdef MNG_OPTIMIZE_FOOTPRINT_COMPOSE
            int i;
            for (i=2; i >= 0; i--)
            {
              iFGg16 = mng_get_uint16 (pDataline+i+i);
                                       /* scale background up */
              iBGg16 = (mng_uint16)(*(pScanline+i));
              iBGg16 = (mng_uint16)((mng_uint32)iBGg16 << 8) | iBGg16;
                                       /* now compose */
              MNG_COMPOSE16(iFGg16, iFGg16, iA16, iBGg16);
                                       /* and return the composed values */
              *(pScanline+i) = (mng_uint8)(iFGg16 >> 8);
            }
#else
              iFGr16 = mng_get_uint16 (pDataline  );
              iFGg16 = mng_get_uint16 (pDataline+2);
              iFGb16 = mng_get_uint16 (pDataline+4);
                                       /* scale background up */
              iBGr16 = (mng_uint16)(*pScanline    );
              iBGg16 = (mng_uint16)(*(pScanline+1));
              iBGb16 = (mng_uint16)(*(pScanline+2));
              iBGr16 = (mng_uint16)((mng_uint32)iBGr16 << 8) | iBGr16;
              iBGg16 = (mng_uint16)((mng_uint32)iBGg16 << 8) | iBGg16;
              iBGb16 = (mng_uint16)((mng_uint32)iBGb16 << 8) | iBGb16;
                                       /* now compose */
              MNG_COMPOSE16(iFGr16, iFGr16, iA16, iBGr16);
              MNG_COMPOSE16(iFGg16, iFGg16, iA16, iBGg16);
              MNG_COMPOSE16(iFGb16, iFGb16, iA16, iBGb16);
                                       /* and return the composed values */
              *pScanline     = (mng_uint8)(iFGr16 >> 8);
              *(pScanline+1) = (mng_uint8)(iFGg16 >> 8);
              *(pScanline+2) = (mng_uint8)(iFGb16 >> 8);
#endif
            }
          }

          pScanline += (pData->iColinc * 3);
          pDataline += 8;
        }
      }
      else
#endif
      {
        for (iX = pData->iSourcel + pData->iCol; iX < pData->iSourcer; iX += pData->iColinc)
        {
          iA8 = *(pDataline+3);        /* get alpha value */

          if (iA8)                     /* any opacity at all ? */
          {
            if (iA8 == 0xFF)           /* fully opaque ? */
            {                          /* then simply copy the values */
              *pScanline     = *pDataline;
              *(pScanline+1) = *(pDataline+1);
              *(pScanline+2) = *(pDataline+2);
            }
            else
            {                          /* do alpha composing */
#ifdef MNG_OPTIMIZE_FOOTPRINT_COMPOSE
              int i;
              for (i=2; i >= 0; i--)
              {
              MNG_COMPOSE8 (*(pScanline+i), *(pDataline+i), iA8, *(pScanline+i));
              }
#else
              MNG_COMPOSE8 (*pScanline,     *pDataline,     iA8, *pScanline    );
              MNG_COMPOSE8 (*(pScanline+1), *(pDataline+1), iA8, *(pScanline+1));
              MNG_COMPOSE8 (*(pScanline+2), *(pDataline+2), iA8, *(pScanline+2));
#endif
            }
          }

          pScanline += (pData->iColinc * 3);
          pDataline += 4;
        }
      }
    }
  }

  check_update_region (pData);

#ifdef MNG_SUPPORT_TRACE
  MNG_TRACE (pData, MNG_FN_DISPLAY_RGB8, MNG_LC_END);
#endif

  return MNG_NOERROR;
}
#endif /* MNG_SKIPCANVAS_RGB8 */

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

#ifndef MNG_SKIPCANVAS_RGBA8
mng_retcode mng_display_rgba8 (mng_datap pData)
{
  mng_uint8p pScanline;
  mng_uint8p pDataline;
  mng_int32  iX;
  mng_uint8  iFGa8, iBGa8, iCa8;
#ifndef MNG_NO_16BIT_SUPPORT
  mng_uint16 iFGa16, iBGa16, iCa16;
#ifndef MNG_OPTIMIZE_FOOTPRINT_COMPOSE
  mng_uint16 iFGr16, iFGg16, iFGb16;
#else
  mng_uint16 iFGg16;
#endif
  mng_uint16 iBGr16, iBGg16, iBGb16;
  mng_uint16 iCr16, iCg16, iCb16;
#endif
  mng_uint8  iCr8, iCg8, iCb8;

#ifdef MNG_SUPPORT_TRACE
  MNG_TRACE (pData, MNG_FN_DISPLAY_RGBA8, MNG_LC_START);
#endif
                                       /* viewable row ? */
  if ((pData->iRow >= pData->iSourcet) && (pData->iRow < pData->iSourceb))
  {                                    /* address destination row */
    pScanline = (mng_uint8p)pData->fGetcanvasline (((mng_handle)pData),
                                                   pData->iRow + pData->iDestt -
                                                   pData->iSourcet);
                                       /* adjust destination row starting-point */
    pScanline = pScanline + (pData->iCol << 2) + (pData->iDestl << 2);
    pDataline = pData->pRGBArow;       /* address source row */

#ifndef MNG_NO_16BIT_SUPPORT
    if (pData->bIsRGBA16)              /* adjust source row starting-point */
      pDataline = pDataline + ((pData->iSourcel / pData->iColinc) << 3);
    else
#endif
      pDataline = pDataline + ((pData->iSourcel / pData->iColinc) << 2);

    if (pData->bIsOpaque)              /* forget about transparency ? */
    {
#ifndef MNG_NO_16BIT_SUPPORT
      if (pData->bIsRGBA16)            /* 16-bit input row ? */
      {