/*
* Initialize Nbody problem
*/
void InitLoc()
{
int k;
Color color[3];
color[0] = Color(1.0,1.0,1.0);
color[1] = Color(1.0,0.9,0.5);
color[2] = Color(0.5,0.9,1.0);
// Allocate room for twice as many bodies to facilitate ping-pong
pos[0] = (float3*)malloc(N*sizeof(float3));
if (!pos[0]) Fatal("Error allocating memory for %d stars\n",N);
pos[1] = (float3*)malloc(N*sizeof(float3));
if (!pos[1]) Fatal("Error allocating memory for %d stars\n",N);
vel = (float3*)malloc(N*sizeof(float3));
if (!vel) Fatal("Error allocating memory for %d stars\n",N);
M = (float*)malloc(N*sizeof(float));
if (!M) Fatal("Error allocating memory for %d stars\n",N);
col = (Color*)malloc(N*sizeof(Color));
if (!col) Fatal("Error allocating memory for %d stars\n",N);
// Assign random locations
for (k=0;k<N;k++)
{
pos[0][k] = rand3(dim/2);
vel[k] = rand3(spd);
col[k] = color[k%3];
M[k] = rand1(mass);
}
// Initialize src
src = 0;
}
double RandomNum::rangau(double avg, double stddev, int * iseed) {
double rangau, fac, rsq, v1, v2, gasdev;
static int iset;
static double gset;
if(*iseed<0){
iset=0;
}
if(iset==0) {
rsq=10;
while((rsq>1)||rsq==0){
v1=2*rand3(iseed)-1;
v2=2*rand3(iseed)-1;
rsq=v1*v1+v2*v2;
}
fac=sqrt(-2*log(rsq)/rsq);
gset=v1*fac;
gasdev=v2*fac;
iset=1;
} else {
gasdev=gset;
iset=0;
}
rangau = avg + stddev*gasdev;
return rangau;
}