ewGrid.cpp 7.1 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
/*
 * EasyWave - A realtime tsunami simulation program with GPU support.
 * Copyright (C) 2014  Andrey Babeyko, Johannes Spazier
 * GFZ German Research Centre for Geosciences (http://www.gfz-potsdam.de)
 *
 * Parts of this program (especially the GPU extension) were developed
 * within the context of the following publicly funded project:
 * - TRIDEC, EU 7th Framework Programme, Grant Agreement 258723
 *   (http://www.tridec-online.eu)
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <utilits.h>
#include "easywave.h"

int NLon,NLat;
double LonMin,LonMax,LatMin,LatMax;
double DLon,DLat;                 // steps in grad
double Dx,Dy;                     // steps in m, dx must be multiplied by cos(y) before use
float *R6;
float *C1;
float *C2;
float *C3;
float *C4;


int ewLoadBathymetry()
{
  FILE *fp;
  char fileLabel[5];
  unsigned short shval;
  int ierr,isBin,i,j,m,k;
  float fval;
  double dval;

  CNode& Node = *gNode;

  Log.print( "Loading bathymetry from %s", Par.fileBathymetry );

  // check if bathymetry file is in ascii or binary format
  if( (fp=fopen(Par.fileBathymetry,"rb")) == NULL ) return Err.post( Err.msgOpenFile(Par.fileBathymetry) );

  memset( fileLabel, 0, 5 );
  ierr = fread( fileLabel, 4, 1, fp );
  if( !strcmp( fileLabel,"DSAA" ) )
    isBin = 0;
  else if( !strcmp( fileLabel,"DSBB" ) )
    isBin = 1;
  else
    return Err.post( "%s: not GRD-file!", Par.fileBathymetry );

  fclose(fp);

  if( isBin ) {
    fp = fopen( Par.fileBathymetry, "rb" );
    ierr = fread( fileLabel, 4, 1, fp );
    ierr = fread( &shval, sizeof(unsigned short), 1, fp ); NLon = shval;
    ierr = fread( &shval, sizeof(unsigned short), 1, fp ); NLat = shval;
  }
  else {
    fp = fopen( Par.fileBathymetry, "rt" );
    ierr = fscanf( fp, "%s", fileLabel );
    ierr = fscanf( fp, " %d %d ", &NLon, &NLat );
  }

  // try to allocate memory for GRIDNODE structure and for caching arrays
  printf_v("Size: %d %d %luMB\n", NLon, NLat, sizeof(float)*MAX_VARS_PER_NODE*NLon*NLat/1024/1024);
  if( Node.mallocMem() ) return Err.post( Err.msgAllocateMem() );

  if( isBin ) {
    ierr = fread( &LonMin, sizeof(double), 1, fp ); ierr = fread( &LonMax, sizeof(double), 1, fp );
    ierr = fread( &LatMin, sizeof(double), 1, fp ); ierr = fread( &LatMax, sizeof(double), 1, fp );
    ierr = fread( &dval, sizeof(double), 1, fp ); ierr = fread( &dval, sizeof(double), 1, fp ); // zmin zmax
  }
  else {
    ierr = fscanf( fp, " %lf %lf ", &LonMin, &LonMax );
    ierr = fscanf( fp, " %lf %lf ", &LatMin, &LatMax );
    ierr = fscanf( fp, " %*s %*s " );   // zmin, zmax
  }

  DLon = (LonMax - LonMin)/(NLon - 1);   // in degrees
  DLat = (LatMax - LatMin)/(NLat - 1);

  Dx = Re * g2r( DLon );     // in m along the equator
  Dy = Re * g2r( DLat );

102 103 104 105 106 107 108 109
  /* NOTE: optimal would be reading everything in one step, but that does not work because rows and columns are transposed
   * (only possible with binary data at all) - use temporary buffer for now (consumes additional memory!) */
  float *buf = new float[ NLat*NLon ];
  ierr = fread( buf, sizeof(float), NLat*NLon, fp );

  for( i=1; i<=NLon; i++ ) {
	for( j=1; j<=NLat; j++ ) {

110 111 112
      m = idx(j,i);

      if( isBin )
113 114
        fval = buf[ (j-1) * NLon + (i-1) ];
    	//ierr = fread( &fval, sizeof(float), 1, fp );
115 116 117 118 119
      else
        ierr = fscanf( fp, " %f ", &fval );

      Node(m, iTopo) = fval;
      Node(m, iTime) = -1;
120 121 122 123 124 125 126 127
      Node(m, iD) = -fval;

	  if( Node(m, iD) < 0 ) {
	    Node(m, iD) = 0.0f;
	  } else if( Node(m, iD) < Par.dmin ) {
		  Node(m, iD) = Par.dmin;
	  }

128 129 130
    }
  }

131 132 133 134 135 136
  delete[] buf;

  for( k=1; k<MAX_VARS_PER_NODE-2; k++ ) {
	  Node.initMemory( k, 0 );
  }

137 138
  fclose( fp );

139
  if( !Par.dt ) { // time step not explicitly defined
140

141 142
	// Make bathymetry from topography. Compute stable time step.
	double dtLoc=RealMax;
143

144 145 146 147 148 149 150
	for( i=1; i<=NLon; i++ ) {
	  for( j=1; j<=NLat; j++ ) {
		  m = idx(j,i);
		  if( Node(m, iD) == 0.0f ) continue;
		  dtLoc = My_min( dtLoc, 0.8 * (Dx*cosdeg(getLat(j))) / sqrt(Gravity*Node(m, iD)) );
	  }
	}
151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227

    Log.print("Stable CFL time step: %g sec", dtLoc);
    if( dtLoc > 15 ) Par.dt = 15;
    else if( dtLoc > 10 ) Par.dt = 10;
    else if( dtLoc > 5 ) Par.dt = 5;
    else if( dtLoc > 2 ) Par.dt = 2;
    else if( dtLoc > 1 ) Par.dt = 1;
    else return Err.post("Bathymetry requires too small time step (<1sec)");
  }

  // Correct bathymetry for edge artefacts
  for( i=1; i<=NLon; i++ ) {
    if( Node(idx(1,i), iD) != 0 && Node(idx(2,i), iD) == 0 ) Node(idx(1,i), iD) = 0.;
    if( Node(idx(NLat,i), iD) != 0 && Node(idx(NLat-1,i), iD) == 0 ) Node(idx(NLat,i), iD) = 0.;
  }
  for( j=1; j<=NLat; j++ ) {
    if( Node(idx(j,1), iD) != 0 && Node(idx(j,2), iD) == 0 ) Node(idx(j,1), iD) = 0.;
    if( Node(idx(j,NLon), iD) != 0 && Node(idx(j,NLon-1), iD) == 0 ) Node(idx(j,NLon), iD) = 0.;
  }


  // Calculate caching grid parameters for speedup
  for( j=1; j<=NLat; j++ ) {
    R6[j] = cosdeg( LatMin + (j-0.5)*DLat );
  }

  for( i=1; i<=NLon; i++ ) {
    for( j=1; j<=NLat; j++ ) {

      m = idx(j,i);

      if( Node(m, iD) == 0 ) continue;

      Node(m, iR1) = Par.dt/Dy/R6[j];

      if( i != NLon ) {
        if( Node(m+NLat, iD) != 0 ) {
          Node(m, iR2) = 0.5*Gravity*Par.dt/Dy/R6[j]*(Node(m, iD)+Node(m+NLat, iD));
          Node(m, iR3) = 0.5*Par.dt*Omega*sindeg( LatMin + (j-0.5)*DLat );
        }
      }
      else {
    	Node(m, iR2) = 0.5*Gravity*Par.dt/Dy/R6[j]*Node(m, iD)*2;
    	Node(m, iR3) = 0.5*Par.dt*Omega*sindeg( LatMin + (j-0.5)*DLat );
      }

      if( j != NLat ) {
        if( Node(m+1, iD) != 0 ) {
          Node(m, iR4) = 0.5*Gravity*Par.dt/Dy*(Node(m, iD)+Node(m+1, iD));
          Node(m, iR5) = 0.5*Par.dt*Omega*sindeg( LatMin + j*DLat );
        }
      }
      /* FIXME: Bug? */
      else {
    	Node(m, iR2) = 0.5*Gravity*Par.dt/Dy*Node(m, iD)*2;
    	Node(m, iR3) = 0.5*Par.dt*Omega*sindeg( LatMin + j*DLat );
      }

    }
  }

  for( i=1; i<=NLon; i++ ) {
    C1[i] = 0;
    if( Node(idx(1,i), iD) != 0 ) C1[i] = 1./sqrt(Gravity*Node(idx(1,i), iD));
    C3[i] = 0;
    if( Node(idx(NLat,i), iD) != 0 ) C3[i] = 1./sqrt(Gravity*Node(idx(NLat,i), iD));
  }

  for( j=1; j<=NLat; j++ ) {
    C2[j] = 0;
    if( Node(idx(j,1), iD) != 0 ) C2[j] = 1./sqrt(Gravity*Node(idx(j,1), iD));
    C4[j] = 0;
    if( Node(idx(j,NLon), iD) != 0 ) C4[j] = 1./sqrt(Gravity*Node(idx(j,NLon), iD));
  }

  return 0;
}