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nilsberglund-orleans
2021-08-15 11:49:37 +02:00
committed by GitHub
parent d227439e84
commit b1d8db471a
12 changed files with 2424 additions and 1052 deletions
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wave_common.c Normal file
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/* functions common to wave_billiard.c, wave_comparison.c, mangrove.c */
void init_xyin(short int * xy_in[NX])
/* initialise table xy_in, needed when obstacles are killed */
// short int * xy_in[NX];
//
{
int i, j;
double xy[2];
for (i=0; i<NX; i++)
for (j=0; j<NY; j++)
{
ij_to_xy(i, j, xy);
xy_in[i][j] = xy_in_billiard(xy[0],xy[1]);
}
}
void init_wave(double x, double y, double *phi[NX], double *psi[NX], short int * xy_in[NX])
/* initialise field with drop at (x,y) - phi is wave height, psi is phi at time t-1 */
{
int i, j;
double xy[2], dist2;
for (i=0; i<NX; i++)
for (j=0; j<NY; j++)
{
ij_to_xy(i, j, xy);
dist2 = (xy[0]-x)*(xy[0]-x) + (xy[1]-y)*(xy[1]-y);
xy_in[i][j] = xy_in_billiard(xy[0],xy[1]);
if ((xy_in[i][j])||(TWOSPEEDS)) phi[i][j] = 0.2*exp(-dist2/0.001)*cos(-sqrt(dist2)/0.01);
else phi[i][j] = 0.0;
psi[i][j] = 0.0;
}
}
void init_planar_wave(double x, double y, double *phi[NX], double *psi[NX], short int * xy_in[NX])
/* initialise field with drop at (x,y) - phi is wave height, psi is phi at time t-1 */
/* beta version, works for vertical planar wave only so far */
{
int i, j;
double xy[2], dist2;
for (i=0; i<NX; i++)
for (j=0; j<NY; j++)
{
ij_to_xy(i, j, xy);
dist2 = (xy[0]-x)*(xy[0]-x);
xy_in[i][j] = xy_in_billiard(xy[0],xy[1]);
// if ((xy_in[i][j])||(TWOSPEEDS)) phi[i][j] = 0.01*exp(-dist2/0.0005)*cos(-sqrt(dist2)/0.01);
// if ((xy_in[i][j])||(TWOSPEEDS)) phi[i][j] = 0.01*exp(-dist2/0.0005)*cos(-sqrt(dist2)/0.02);
// if ((xy_in[i][j])||(TWOSPEEDS)) phi[i][j] = 0.01*exp(-dist2/0.005)*cos(-sqrt(dist2)/0.02);
// if ((xy_in[i][j])||(TWOSPEEDS)) phi[i][j] = 0.01*exp(-dist2/0.01)*cos(-sqrt(dist2)/0.02);
if ((xy_in[i][j])||(TWOSPEEDS)) phi[i][j] = 0.01*exp(-dist2/0.0005)*cos(-sqrt(dist2)/0.01);
// if ((xy_in[i][j])||(TWOSPEEDS)) phi[i][j] = 0.01*exp(-dist2/0.05)*cos(-sqrt(dist2)/0.025);
else phi[i][j] = 0.0;
psi[i][j] = 0.0;
}
}
void init_wave_flat( double *phi[NX], double *psi[NX], short int * xy_in[NX])
/* initialise flat field - phi is wave height, psi is phi at time t-1 */
{
int i, j;
double xy[2], dist2;
for (i=0; i<NX; i++)
for (j=0; j<NY; j++)
{
ij_to_xy(i, j, xy);
xy_in[i][j] = xy_in_billiard(xy[0],xy[1]);
phi[i][j] = 0.0;
psi[i][j] = 0.0;
}
}
void add_drop_to_wave(double factor, double x, double y, double *phi[NX], double *psi[NX])
/* add drop at (x,y) to the field with given prefactor */
{
int i, j;
double xy[2], dist2;
for (i=0; i<NX; i++)
for (j=0; j<NY; j++)
{
ij_to_xy(i, j, xy);
dist2 = (xy[0]-x)*(xy[0]-x) + (xy[1]-y)*(xy[1]-y);
phi[i][j] += 0.2*factor*exp(-dist2/0.001)*cos(-sqrt(dist2)/0.01);
}
}
void oscillate_linear_wave(double amplitude, double t, double x1, double y1, double x2, double y2, double *phi[NX],
double *psi[NX])
/* oscillating boundary condition at (x,y), beta version */
{
int i, j, ij1[2], ij2[2], imin, imax, jmin, jmax, d = 5;
double xy[2], dist2;
xy_to_ij(x1, y1, ij1);
xy_to_ij(x2, y2, ij2);
imin = ij1[0] - d; if (imin < 0) imin = 0;
imax = ij2[0] + d; if (imax >= NX) imax = NX-1;
jmin = ij1[1] - d; if (jmin < 0) jmin = 0;
jmax = ij2[1] + d; if (jmax >= NY) jmax = NY-1;
for (i = imin; i < imax; i++)
for (j = jmin; j < jmax; j++)
{
ij_to_xy(i, j, xy);
dist2 = (xy[0]-x1)*(xy[0]-x1); /* to be improved */
// dist2 = (xy[0]-x)*(xy[0]-x) + (xy[1]-y)*(xy[1]-y);
// if (dist2 < 0.01)
if (dist2 < 0.001)
phi[i][j] = amplitude*exp(-dist2/0.001)*cos(-sqrt(dist2)/0.01)*cos(t*OMEGA);
// phi[i][j] += 0.2*exp(-dist2/0.001)*cos(-sqrt(dist2)/0.01)*cos(t*OMEGA);
}
}
double compute_energy(double *phi[NX], double *psi[NX], short int *xy_in[NX], int i, int j)
{
double velocity, energy, gradientx2, gradienty2;
int iplus, iminus, jplus, jminus;
velocity = (phi[i][j] - psi[i][j]);
iplus = (i+1); if (iplus == NX) iplus = NX-1;
iminus = (i-1); if (iminus == -1) iminus = 0;
jplus = (j+1); if (jplus == NY) jplus = NY-1;
jminus = (j-1); if (jminus == -1) jminus = 0;
gradientx2 = (phi[iplus][j]-phi[i][j])*(phi[iplus][j]-phi[i][j])
+ (phi[i][j] - phi[iminus][j])*(phi[i][j] - phi[iminus][j]);
gradienty2 = (phi[i][jplus]-phi[i][j])*(phi[i][jplus]-phi[i][j])
+ (phi[i][j] - phi[i][jminus])*(phi[i][j] - phi[i][jminus]);
if (xy_in[i][j]) return(E_SCALE*E_SCALE*(velocity*velocity + 0.5*COURANT*COURANT*(gradientx2+gradienty2)));
else if (TWOSPEEDS) return(E_SCALE*E_SCALE*(velocity*velocity + 0.5*COURANTB*COURANTB*(gradientx2+gradienty2)));
else return(0);
}
double compute_variance(double *phi[NX], double *psi[NX], short int *xy_in[NX])
/* compute the variance of the field, to adjust color scheme */
{
int i, j, n = 0;
double variance = 0.0;
for (i=1; i<NX; i++)
for (j=1; j<NY; j++)
{
if (xy_in[i][j])
{
n++;
variance += phi[i][j]*phi[i][j];
}
}
if (n==0) n=1;
return(variance/(double)n);
}
double compute_dissipation(double *phi[NX], double *psi[NX], short int *xy_in[NX], double x, double y)
{
double velocity;
int ij[2];
xy_to_ij(x, y, ij);
velocity = (phi[ij[0]][ij[1]] - psi[ij[0]][ij[1]]);
return(velocity*velocity);
}
void draw_wave(double *phi[NX], double *psi[NX], short int *xy_in[NX], double scale, int time, int plot)
/* draw the field */
{
int i, j, iplus, iminus, jplus, jminus;
double rgb[3], xy[2], x1, y1, x2, y2, velocity, energy, gradientx2, gradienty2;
static double dtinverse = ((double)NX)/(COURANT*(XMAX-XMIN)), dx = (XMAX-XMIN)/((double)NX);
glBegin(GL_QUADS);
// printf("dtinverse = %.5lg\n", dtinverse);
for (i=0; i<NX; i++)
for (j=0; j<NY; j++)
{
if ((TWOSPEEDS)||(xy_in[i][j]))
{
if (plot == P_AMPLITUDE)
color_scheme(COLOR_SCHEME, phi[i][j], scale, time, rgb);
else if (plot == P_ENERGY)
color_scheme(COLOR_SCHEME, compute_energy(phi, psi, xy_in, i, j), scale, time, rgb);
else if (plot == P_MIXED)
{
if (j > NY/2) color_scheme(COLOR_SCHEME, phi[i][j], scale, time, rgb);
else color_scheme(COLOR_SCHEME, compute_energy(phi, psi, xy_in, i, j), scale, time, rgb);
}
glColor3f(rgb[0], rgb[1], rgb[2]);
glVertex2i(i, j);
glVertex2i(i+1, j);
glVertex2i(i+1, j+1);
glVertex2i(i, j+1);
}
}
glEnd ();
}