#include "tenv.h"

#include "tsystem.h"

#include "ino_common.h"

#include "tfxparam.h"

#include <sstream> /* std::ostringstream */</sstream>

/* copy and paste from

 igs_ifx_common.h */

namespace igs {

namespace image {

namespace rgba {

enum num { blu = 0, gre, red, alp, siz };

}

}  // namespace image

}  // namespace igs

//------------------------------------------------------------

namespace {

// T is TPixel32 or TPixel64

// U is unsigned char or unsigned short

template <class class="" t,="" u=""></class>

void ras_to_arr_(const TRasterPT<t> ras, U* arr, const int channels) {</t>

  using namespace igs::image::rgba;

  for (int yy = 0; yy < ras->getLy(); ++yy) {

    const T* ras_sl = ras->pixels(yy);

    for (int xx = 0; xx < ras->getLx(); ++xx, arr += channels) {

      if (red < channels) {

        arr[red] = ras_sl[xx].r;

      }

      if (gre < channels) {

        arr[gre] = ras_sl[xx].g;

      }

      if (blu < channels) {

        arr[blu] = ras_sl[xx].b;

      }

      if (alp < channels) {

        arr[alp] = ras_sl[xx].m;

      }

    }

  }

}

template <class class="" t="" u,=""></class>

void arr_to_ras_(const U* arr, const int channels, TRasterPT<t> ras,</t>

                 const int margin  // default is 0

) {

  arr +=

      (ras->getLx() + margin + margin) * margin * channels + margin * channels;

  using namespace igs::image::rgba;

  for (int yy = 0; yy < ras->getLy();

       ++yy, arr += (ras->getLx() + margin + margin) * channels) {

    const U* arrx = arr;

    T* ras_sl     = ras->pixels(yy);

    for (int xx = 0; xx < ras->getLx(); ++xx, arrx += channels) {

      if (red < channels) {

        ras_sl[xx].r = arrx[red];

      }

      if (gre < channels) {

        ras_sl[xx].g = arrx[gre];

      }

      if (blu < channels) {

        ras_sl[xx].b = arrx[blu];

      }

      if (alp < channels) {

        ras_sl[xx].m = arrx[alp];

      }

    }

  }

}

}  // namespace

//--------------------

void ino::ras_to_arr(const TRasterP in_ras, const int channels,

                     unsigned char* out_arr) {

  if ((TRaster32P)in_ras) {

    ras_to_arr_<tpixel32, char="" unsigned="">(in_ras, out_arr, channels);</tpixel32,>

  } else if ((TRaster64P)in_ras) {

    ras_to_arr_<tpixel64, short="" unsigned="">(</tpixel64,>

        in_ras, reinterpret_cast<unsigned short*="">(out_arr), channels);</unsigned>

  }

}

void ino::arr_to_ras(const unsigned char* in_arr, const int channels,

                     TRasterP out_ras, const int margin) {

  if ((TRaster32P)out_ras) {

    arr_to_ras_<unsigned char,="" tpixel32="">(in_arr, channels, out_ras, margin);</unsigned>

  } else if ((TRaster64P)out_ras) {

    arr_to_ras_<unsigned short,="" tpixel64="">(</unsigned>

        reinterpret_cast<const short*="" unsigned="">(in_arr), channels, out_ras,</const>

        margin);

  }

}

//--------------------

void ino::ras_to_vec(const TRasterP in_ras, const int channels,

                     std::vector<unsigned char="">& out_vec) {</unsigned>

  out_vec.resize(

      in_ras->getLy() * in_ras->getLx() * channels *

      (((TRaster64P)in_ras) ? sizeof(unsigned short) : sizeof(unsigned char)));

  ino::ras_to_arr(in_ras, channels, &out_vec.at(0));

}

void ino::vec_to_ras(std::vector<unsigned char="">& in_vec, const int channels,</unsigned>

                     TRasterP out_ras, const int margin  // default is 0

) {

  ino::arr_to_ras(&in_vec.at(0), channels, out_ras, margin);

  in_vec.clear();

}

//--------------------

#if 0   //---

void ino::Lx_to_wrap( TRasterP ras ) {

	/*

	ras->getLx()   : 描画の幅

	ras->getWrap() : データの存在幅

	描画幅よりデータの存在幅の方が大きい場合、

	存在幅位置に置き直し、残りをゼロクリア

	*/

	if ( ras->getWrap() <= ras->getLx() ) { return; }

	const int rowSize  = ras->getLx()   * ras->getPixelSize();

	const int wrapSize = ras->getWrap() * ras->getPixelSize();

	const int restSize = wrapSize - rowSize;

	const UCHAR *rowImg  = ras->getRawData()+rowSize *(ras->getLy()-1);

	      UCHAR *wrapImg = ras->getRawData()+wrapSize*(ras->getLy()-1);

	for (int yy = 0; yy < ras->getLy(); ++yy) {

		::memcpy(wrapImg, rowImg, rowSize);

		::memset(wrapImg+rowSize, 0, restSize); /* 上下にはみ出すとここで落ちる */

		rowImg  -= rowSize;

		wrapImg -= wrapSize;

	}

}

#endif  //---

//------------------------------------------------------------

namespace {

bool enable_sw_ = true;

bool check_sw_  = true;

}  // namespace

bool ino::log_enable_sw(void) {

  if (check_sw_) {

    TFileStatus file(

        // ToonzFolder::getProfileFolder()

        TEnv::getConfigDir() + "fx_ino_no_log.setup");

    if (file.doesExist()) {

      enable_sw_ = false;

    }

    check_sw_ = false;

  }

  return enable_sw_;

}

//------------------------------------------------------------

namespace {

/* より大きな四角エリアにPixel整数値で密着する */

void makeRectCoherent(TRectD& rect, const TPointD& pos) {

  rect -= pos;

  rect.x0 = tfloor(rect.x0); /* ((x)<(int)(x)? (int)(x)-1: (int)(x))*/

  rect.y0 = tfloor(rect.y0);

  rect.x1 = tceil(rect.x1); /* ((int)(x)<(x)? (int)(x)+1: (int)(x))*/

  rect.y1 = tceil(rect.y1);

  rect += pos;

}

inline void to_xyz(double* xyz, double const* bgr) {

  xyz[0] = 0.6069 * bgr[2] + 0.1735 * bgr[1] + 0.2003 * bgr[0];  // X

  xyz[1] = 0.2989 * bgr[2] + 0.5866 * bgr[1] + 0.1145 * bgr[0];  // Y

  xyz[2] = 0.0000 * bgr[2] + 0.0661 * bgr[1] + 1.1162 * bgr[0];  // Z

}

inline void to_bgr(double* bgr, double const* xyz) {

  bgr[0] = +0.0585 * xyz[0] - 0.1187 * xyz[1] + 0.9017 * xyz[2];  // blue

  bgr[1] = -0.9844 * xyz[0] + 1.9985 * xyz[1] - 0.0279 * xyz[2];  // green

  bgr[2] = +1.9104 * xyz[0] - 0.5338 * xyz[1] - 0.2891 * xyz[2];  // red

}

// convert sRGB color space to power space

template <typename t="double"></typename>

inline T to_linear_color_space(T nonlinear_color, T exposure, T gamma) {

  // return -std::log(T(1) - std::pow(nonlinear_color, gamma)) / exposure;

  return std::pow(nonlinear_color, gamma) / exposure;

}

// convert power space to sRGB color space

template <typename t="double"></typename>

inline T to_nonlinear_color_space(T linear_color, T exposure, T gamma) {

  // return std::pow(T(1) - std::exp(-exposure * linear_color), T(1) / gamma);

  return std::pow(linear_color * exposure, T(1) / gamma);

}

template <class t="double"></class>

const T& clamp(const T& v, const T& lo, const T& hi) {

  assert(!(hi < lo));

  return (v < lo) ? lo : (hi < v) ? hi : v;

}

}  // namespace

//------------------------------------------------------------

TBlendForeBackRasterFx::TBlendForeBackRasterFx(bool clipping_mask,

                                               bool has_alpha_option)

    : m_opacity(1.0 * ino::param_range())

    , m_clipping_mask(clipping_mask)

    , m_linear(false)

    , m_gamma(2.2)

    , m_premultiplied(true) {

  addInputPort("Fore", this->m_up);

  addInputPort("Back", this->m_down);

  bindParam(this, "opacity", this->m_opacity);

  bindParam(this, "clipping_mask", this->m_clipping_mask);

  bindParam(this, "linear", this->m_linear);

  bindParam(this, "gamma", this->m_gamma);

  bindParam(this, "premultiplied", this->m_premultiplied);

  this->m_opacity->setValueRange(0, 1.0 * ino::param_range());

  this->m_gamma->setValueRange(0.2, 5.0);

  if (has_alpha_option) {

    m_alpha_rendering = TBoolParamP(true);

    bindParam(this, "alpha_rendering", this->m_alpha_rendering);

  }

}

//------------------------------------------------------------

bool TBlendForeBackRasterFx::doGetBBox(double frame, TRectD& bBox,

                                       const TRenderSettings& rs) {

  TRectD up_bx;

  const bool up_sw =

      (m_up.isConnected() ? m_up->doGetBBox(frame, up_bx, rs) : false);

  TRectD dn_bx;

  const bool dn_sw =

      (m_down.isConnected() ? m_down->doGetBBox(frame, dn_bx, rs) : false);

  if (up_sw && dn_sw) {

    bBox = up_bx + dn_bx;

    return !bBox.isEmpty();

  } else if (up_sw) {

    bBox = up_bx;

    return true;

  } else if (dn_sw) {

    bBox = dn_bx;

    return true;

  } else {

    bBox = TRectD();

    return false;

  }

}

//------------------------------------------------------------

void TBlendForeBackRasterFx::dryComputeUpAndDown(TRectD& rect, double frame,

                                                 const TRenderSettings& rs,

                                                 bool upComputesWholeTile) {

  const bool up_is   = (this->m_up.isConnected() &&

                      this->m_up.getFx()->getTimeRegion().contains(frame));

  const bool down_is = (this->m_down.isConnected() &&

                        this->m_down.getFx()->getTimeRegion().contains(frame));

  /* ------ 両方とも切断の時処理しない ---------------------- */

  if (!up_is && !down_is) {

    return;

  }

  /* ------ up接続かつdown切断の時 -------------------------- */

  if (up_is && !down_is) {

    this->m_up->dryCompute(rect, frame, rs);

    return;

  }

  /* ------ down接続時 -------------------------------------- */

  if (down_is) {

    this->m_down->dryCompute(rect, frame, rs);

  }

  /* ------ up切断時 ---------------------------------------- */

  if (!up_is) {

    return;

  }

  /* ------ tileのgeometryを計算する ------------------------ */

  TRectD upBBox;

  if (upComputesWholeTile) {

    upBBox = rect;

  } else {

    this->m_up->getBBox(frame, upBBox, rs);

    upBBox *= rect;

    makeRectCoherent(upBBox, rect.getP00());

  }

  if ((upBBox.getLx() > 0.5) && (upBBox.getLy() > 0.5)) {

    this->m_up->dryCompute(upBBox, frame, rs);

  }

}

//------------------------------------------------------------

void TBlendForeBackRasterFx::doCompute(TTile& tile, double frame,

                                       const TRenderSettings& rs) {

  /* ------ 画像生成 ---------------------------------------- */

  TRasterP dn_ras, up_ras;

  this->computeUpAndDown(tile, frame, rs, dn_ras, up_ras);

  if (!up_ras) {

    return;

  }

  // blend on the empty raster if the back port is not active

  if (!dn_ras) {

    dn_ras = tile.getRaster();

  }

  /* ------ 動作パラメータを得る ---------------------------- */

  const double up_opacity =

      this->m_opacity->getValue(frame) / ino::param_range();

  const double gamma = this->m_gamma->getValue(frame);

  /* ------ (app_begin)log記憶 ------------------------------ */

  const bool log_sw = ino::log_enable_sw();

  if (log_sw) {

    std::ostringstream os;

    os << "params"

       << "  up_opacity " << up_opacity << "   dn_tile w " << dn_ras->getLx()

       << "  wrap " << dn_ras->getWrap() << "  h " << dn_ras->getLy()

       << "  pixbits " << ino::pixel_bits(dn_ras) << "   up_tile w "

       << up_ras->getLx() << "  wrap " << up_ras->getWrap() << "  h "

       << up_ras->getLy() << "  pixbits " << ino::pixel_bits(up_ras)

       << "   frame " << frame;

  }

  /* ------ fx処理 ------------------------------------------ */

  try {

    if (dn_ras) {

      dn_ras->lock();

    }

    if (up_ras) {

      up_ras->lock();

    }

    doComputeFx(dn_ras, up_ras, TPoint(), up_opacity, gamma);

    // fx_(dn_ras, up_ras, TPoint(), up_opacity,

    // this->m_clipping_mask->getValue(),

    //  this->m_linear->getValue(), gamma, this->m_premultiplied->getValue());

    if (up_ras) {

      up_ras->unlock();

    }

    if (dn_ras) {

      dn_ras->unlock();

    }

  }

  /* ------ error処理 --------------------------------------- */

  catch (std::exception& e) {

    if (up_ras) {

      up_ras->unlock();

    }

    if (dn_ras) {

      dn_ras->unlock();

    }

    if (log_sw) {

      std::string str("exception <");

      str += e.what();

      str += '>';

    }

    throw;

  } catch (...) {

    if (up_ras) {

      up_ras->unlock();

    }

    if (dn_ras) {

      dn_ras->unlock();

    }

    if (log_sw) {

      std::string str("other exception");

    }

    throw;

  }

}

//------------------------------------------------------------

void TBlendForeBackRasterFx::doComputeFx(TRasterP& dn_ras_out,

                                         const TRasterP& up_ras,

                                         const TPoint& pos,

                                         const double up_opacity,

                                         const double gamma) {

  /* 交差したエリアを処理するようにする、いるのか??? */

  TRect outRect(dn_ras_out->getBounds());

  TRect upRect(up_ras->getBounds() + pos);

  TRect intersection = outRect * upRect;

  if (intersection.isEmpty()) return;

  TRasterP cRout = dn_ras_out->extract(intersection);

  TRect rr       = intersection - pos;

  TRasterP cRup  = up_ras->extract(rr);

  TRaster32P rout32 = cRout, rup32 = cRup;

  TRaster64P rout64 = cRout, rup64 = cRup;

  bool linear_sw = this->m_linear->getValue();

  if (rout32 && rup32) {

    if (linear_sw)

      linearTmpl<tpixel32, uchar="">(rout32, rup32, up_opacity, gamma);</tpixel32,>

    // linearAdd<tpixel32, uchar="">(rout32, rup32, up_opacity, clipping_mask_sw,</tpixel32,>

    //  gamma, premultiplied_sw);

    else

      nonlinearTmpl<tpixel32, uchar="">(rout32, rup32, up_opacity);</tpixel32,>

    // tmpl_<tpixel32, uchar="">(rout32, rup32, up_opacity, clipping_mask_sw);</tpixel32,>

  } else if (rout64 && rup64) {

    if (linear_sw)

      linearTmpl<tpixel64, ushort="">(rout64, rup64, up_opacity, gamma);</tpixel64,>

    else

      nonlinearTmpl<tpixel64, ushort="">(rout64, rup64, up_opacity);</tpixel64,>

  } else {

    throw TRopException("unsupported pixel type");

  }

}

//------------------------------------------------------------

template <class class="" q="" t,=""></class>

void TBlendForeBackRasterFx::nonlinearTmpl(TRasterPT<t> dn_ras_out,</t>

                                           const TRasterPT<t>& up_ras,</t>

                                           const double up_opacity) {

  bool clipping_mask_sw   = this->m_clipping_mask->getValue();

  bool alpha_rendering_sw = (m_alpha_rendering.getPointer())

                                ? this->m_alpha_rendering->getValue()

                                : true;

  double maxi = static_cast<double>(T::maxChannelValue);  // 255or65535</double>

  assert(dn_ras_out->getSize() == up_ras->getSize());

  for (int yy = 0; yy < dn_ras_out->getLy(); ++yy) {

    T* out_pix             = dn_ras_out->pixels(yy);

    const T* const out_end = out_pix + dn_ras_out->getLx();

    const T* up_pix        = up_ras->pixels(yy);

    for (; out_pix < out_end; ++out_pix, ++up_pix) {

      double upr = static_cast<double>(up_pix->r) / maxi;</double>

      double upg = static_cast<double>(up_pix->g) / maxi;</double>

      double upb = static_cast<double>(up_pix->b) / maxi;</double>

      double upa = static_cast<double>(up_pix->m) / maxi;</double>

      double dnr = static_cast<double>(out_pix->r) / maxi;</double>

      double dng = static_cast<double>(out_pix->g) / maxi;</double>

      double dnb = static_cast<double>(out_pix->b) / maxi;</double>

      double dna = static_cast<double>(out_pix->m) / maxi;</double>

      brendKernel(dnr, dng, dnb, dna, upr, upg, upb, upa,

                  clipping_mask_sw ? up_opacity * dna : up_opacity,

                  alpha_rendering_sw);

      out_pix->r = static_cast<q>(dnr * (maxi + 0.999999));</q>

      out_pix->g = static_cast<q>(dng * (maxi + 0.999999));</q>

      out_pix->b = static_cast<q>(dnb * (maxi + 0.999999));</q>

      out_pix->m = static_cast<q>(dna * (maxi + 0.999999));</q>

    }

  }

}

//------------------------------------------------------------

template <class class="" q="" t,=""></class>

void TBlendForeBackRasterFx::linearTmpl(TRasterPT<t> dn_ras_out,</t>

                                        const TRasterPT<t>& up_ras,</t>

                                        const double up_opacity,

                                        const double gamma) {

  bool clipping_mask_sw   = this->m_clipping_mask->getValue();

  bool alpha_rendering_sw = (m_alpha_rendering.getPointer())

                                ? this->m_alpha_rendering->getValue()

                                : true;

  bool premultiplied_sw = this->m_premultiplied->getValue();

  double maxi  = static_cast<double>(T::maxChannelValue);  // 255or65535</double>

  double limit = (maxi + 0.5) / (maxi + 1.0);

  assert(dn_ras_out->getSize() == up_ras->getSize());

  for (int yy = 0; yy < dn_ras_out->getLy(); ++yy) {

    T* out_pix             = dn_ras_out->pixels(yy);

    const T* const out_end = out_pix + dn_ras_out->getLx();

    const T* up_pix        = up_ras->pixels(yy);

    for (; out_pix < out_end; ++out_pix, ++up_pix) {

      if (up_pix->m <= 0 || up_opacity <= 0) {

        continue;

      }

      double dna         = static_cast<double>(out_pix->m) / maxi;</double>

      double tmp_opacity = clipping_mask_sw ? up_opacity * dna : up_opacity;

      if (tmp_opacity <= 0) continue;

      double dnBGR[3];

      dnBGR[0]        = static_cast<double>(out_pix->b) / maxi;</double>

      dnBGR[1]        = static_cast<double>(out_pix->g) / maxi;</double>

      dnBGR[2]        = static_cast<double>(out_pix->r) / maxi;</double>

      double dnXYZ[3] = {0.0, 0.0, 0.0};

      if (dna > 0.0) {

        for (int c = 0; c < 3; c++) {

          if (premultiplied_sw)

            dnBGR[c] = to_linear_color_space(dnBGR[c] / dna, 1.0, gamma) * dna;

          else

            dnBGR[c] = to_linear_color_space(dnBGR[c], 1.0, gamma);

        }

        to_xyz(dnXYZ, dnBGR);

      }

      double upBGR[3];

      upBGR[0]   = static_cast<double>(up_pix->b) / maxi;</double>

      upBGR[1]   = static_cast<double>(up_pix->g) / maxi;</double>

      upBGR[2]   = static_cast<double>(up_pix->r) / maxi;</double>

      double upa = static_cast<double>(up_pix->m) / maxi;</double>

      for (int c = 0; c < 3; c++) {

        if (premultiplied_sw)

          upBGR[c] = to_linear_color_space(upBGR[c] / upa, 1.0, gamma) * upa;

        else

          upBGR[c] = to_linear_color_space(upBGR[c], 1.0, gamma);

      }

      double upXYZ[3];

      to_xyz(upXYZ, upBGR);

      brendKernel(dnXYZ[0], dnXYZ[1], dnXYZ[2], dna, upXYZ[0], upXYZ[1],

                  upXYZ[2], upa, tmp_opacity, alpha_rendering_sw, true);

      to_bgr(dnBGR, dnXYZ);

      // premultiply the result

      double nonlinear_b =

          to_nonlinear_color_space(dnBGR[0] / dna, 1.0, gamma) * dna;

      double nonlinear_g =

          to_nonlinear_color_space(dnBGR[1] / dna, 1.0, gamma) * dna;

      double nonlinear_r =

          to_nonlinear_color_space(dnBGR[2] / dna, 1.0, gamma) * dna;

      out_pix->r =

          static_cast<q>(clamp(nonlinear_r, 0.0, 1.0) * (maxi + 0.999999));</q>

      out_pix->g =

          static_cast<q>(clamp(nonlinear_g, 0.0, 1.0) * (maxi + 0.999999));</q>

      out_pix->b =

          static_cast<q>(clamp(nonlinear_b, 0.0, 1.0) * (maxi + 0.999999));</q>

      out_pix->m = static_cast<q>(dna * (maxi + 0.999999));</q>

    }

  }

}

//------------------------------------------------------------

void TBlendForeBackRasterFx::computeUpAndDown(TTile& tile, double frame,

                                              const TRenderSettings& rs,

                                              TRasterP& dn_ras,

                                              TRasterP& up_ras,

                                              bool upComputesWholeTile) {

  /* ------ サポートしていないPixelタイプはエラーを投げる --- */

  if (!((TRaster32P)tile.getRaster()) && !((TRaster64P)tile.getRaster())) {

    throw TRopException("unsupported input pixel type");

  }

  /*

m_down,m_upは繋がっている方があればそれを表示する

両方とも接続していれば合成処理する

表示スイッチを切ってあるならm_upを表示する

fxをreplaceすると、

  m_source   --> m_up  (=port0)

  m_reference --> m_down(=port1)

となる

*/

  const bool up_is   = (this->m_up.isConnected() &&

                      this->m_up.getFx()->getTimeRegion().contains(frame));

  const bool down_is = (this->m_down.isConnected() &&

                        this->m_down.getFx()->getTimeRegion().contains(frame));

  /* ------ 両方とも切断の時処理しない ---------------------- */

  if (!up_is && !down_is) {

    tile.getRaster()->clear();

    return;

  }

  /* ------ up接続かつdown切断の時 -------------------------- */

  if (up_is && !down_is) {

    TTile upTile;

    this->m_up->allocateAndCompute(upTile, tile.m_pos,

                                   tile.getRaster()->getSize(),

                                   tile.getRaster(), frame, rs);

    up_ras = upTile.getRaster();

    return;

  }

  /* ------ down接続時 downのみ描画して... ------------------ */

  if (down_is) {

    this->m_down->compute(tile, frame, rs);

  }

  /* ------ up切断時 ---------------------------------------- */

  if (!up_is) {

    return;

  }

  /* upと重なる部分を描画する */

  /* ------ tileの範囲 -------------------------------------- */

  const TDimension tsz(tile.getRaster()->getSize()); /* 整数 */

  const TRectD tileRect(tile.m_pos, TDimensionD(tsz.lx, tsz.ly));

  TRectD upBBox;

  if (upComputesWholeTile) {

    upBBox = tileRect;

  }      /* tile全体を得る */

  else { /* 厳密なエリア... */

    this->m_up->getBBox(frame, upBBox, rs);

    upBBox *= tileRect; /* upとtileの交差エリア */

    /* より大きな四角エリアにPixel整数値で密着する */

    makeRectCoherent(upBBox, tile.m_pos);  // double-->int grid

  }

  TDimensionI upSize(                        /* TRectDをTDimensionIに変換 */

                     tround(upBBox.getLx())  // getLx() = "x1>=x0?x1-x0:0"

                     ,

                     tround(upBBox.getLy())  // getLy() = "y1>=y0?y1-y0:0"

  );

  if ((upSize.lx <= 0) || (upSize.ly <= 0)) {

    return;

  }

  /* ------ upのメモリ確保と描画 ---------------------------- */

  TTile upTile;

  this->m_up->allocateAndCompute(upTile, upBBox.getP00(), upSize,

                                 tile.getRaster() /* 32/64bitsの判定に使う */

                                 ,

                                 frame, rs);

  /* ------ upとdownのTRasterを得る ------------------------- */

  TRectI dnRect(upTile.getRaster()->getSize());  // TDimensionI(-)

  dnRect += convert(upTile.m_pos - tile.m_pos); /* uptile->tile原点 */

  /*

  ここで問題はdoubleの位置を、四捨五入して整数値にしていること

  移動してから四捨五入ではないの???

  dnRectの元位置が整数位置なので、問題ないか...

  */

  dn_ras = upComputesWholeTile ? tile.getRaster()

                               : tile.getRaster()->extract(dnRect);

  up_ras = upTile.getRaster();

  assert(dn_ras->getSize() == up_ras->getSize());

}