waterdepthWCA2Dv1.ca

/*
    
Copyright (c) 2013 Centre for Water Systems,
                   University of Exeter

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.

*/

// Update the water depth with the outflux for teh WCA2Dv1 model,
// This version store the total amount of flux in m^3 passed through the edge.
// ATTENTION The Water depth of the boundary cells (bit 31
// mask) is updated. The bounday cell should have only influx.

CA_FUNCTION waterdepthWCA2Dv1(CA_GRID grid, CA_CELLBUFF_REAL_IO WD, CA_EDGEBUFF_REAL_I OUTF, 
			      CA_EDGEBUFF_REAL_IO TOTOUTF, CA_CELLBUFF_STATE_I MASK, 
			      CA_GLOB_REAL_I dt, CA_GLOB_REAL_I updatedt)
{
  // Initialise the grid
  CA_GRID_INIT(grid);

  // Create the array which will contain the water fluxes on the
  // edges.
  CA_ARRAY_CREATE(grid, CA_REAL, FLUXES, caEdges+1);

  // Create the array which will contain the total water fluxes on the
  // edges.
  CA_ARRAY_CREATE(grid, CA_REAL, TOTFLUXES, caEdges+1);

  // Read Mask of the main cell.
  CA_STATE mask  = caReadCellBuffState(grid,MASK,0);

  // Read bit 0  (false the main cell has nodata)
  CA_STATE bit0  = caReadBitsState(mask,0,1);

  // Read bit 31 (true if the main cell is nodata in at least one
  // neighbour has data)
  CA_STATE bit31  = caReadBitsState(mask,31,32);

  // If the main cell has no data and none of the neighbour has data,
  // then do nothing.
  if(bit0 == 0 && bit31 == 0)
    return;

  // Retrive the current value of the water depth.
  CA_REAL  wd  = caReadCellBuffReal(grid,WD,0);

  // Retrive the area of the main cell.
  CA_REAL  area = caArea(grid,0);

  // Read the fluxes of the main cell.
  caReadEdgeBuffRealEdgeArray(grid, OUTF,0, FLUXES);

  // Read the total fluxes of the main cell.
  caReadEdgeBuffRealEdgeArray(grid, TOTOUTF, 0, TOTFLUXES);

  CA_REAL outflux = 0.0;

  // Loop through the edges.
  for(int e=1; e<=caEdges; e++)
  {
    // If the edge is one of the edges that can be updated without
    // overwriting the buffer, the outflux is positive otherwise is
    // negative.
    if(e<=caUpdateEdges(grid))
      outflux += FLUXES[e];
    else
      outflux -= FLUXES[e];    
  }
    
  // Remove the outflux volume from the next step of the water depth
  caWriteCellBuffReal(grid,WD,wd-(outflux/area));

  // Loop through the edges that can be updated.
  for(int e=1; e<=caUpdateEdges(grid); e++)
  {    
    // compute the  totalflux of an update step.
    CA_REAL totflux = FLUXES[e] + TOTFLUXES[e];

    // Write the new value on the edge.
    caWriteEdgeBuffReal(grid, TOTOUTF, e, totflux);
  }
}