void MACStableFluids::init()
{
/*
for(int j=0; j<u.NJ(); ++j)
for(int i=0; i<u.NI(); ++i)
u(i,j) = std::sin(3.14159 * i / float(u.NI()));
for(int j=0; j<v.NJ(); ++j)
for(int i=0; i<v.NI(); ++i)
v(i,j) = std::sin(3.14159 * j / float(u.NJ()));
*/
for(int i=2; i<u.NI()/3-2; ++i)
for(int j=2; j<u.NJ()/3-2; ++j)
{
v(3*i,3*j,u.NK()/2)=10;
v(3*i+1,3*j,u.NK()/2)=-10;
u(3*i+1,3*j-1,u.NK()/2)=-10;
u(3*i+1,3*j,u.NK()/2)=10;
}
u(u.NI()/2, u.NJ()/2,u.NK()/2 )=10;
for(int i=0; i<size<NGrid>(); ++i)
{
float x=randhashf(i*3,0,1);
float y=randhashf(i*3+1,0,1);
float z=randhashf(i*3+2,0,1);
particles.push_back(Vector3(x,y,z));
}
}
//8 particles per cell
void FluidSim::set_liquid(float (*phi)(const Vec3f&)) {
//surface.reset_phi(phi, dx, Vec3f(0.5f*dx,0.5f*dx,0.5f*dx), ni, nj, nk);
//initialize particles
int seed = 0;
for(int k = 0; k < nk; ++k) for(int j = 0; j < nj; ++j) for(int i = 0; i < ni; ++i) {
Vec3f pos(i*dx,j*dx,k*dx);
float a = randhashf(seed++); float b = randhashf(seed++); float c = randhashf(seed++);
pos += dx * Vec3f(a,b,c);
if(phi(pos) <= -particle_radius) {
float solid_phi = interpolate_value(pos/dx, nodal_solid_phi);
if(solid_phi >= 0){
particles.push_back(pos);
particlesVel.push_back(Vec3f(0,0,0));
particlesCell.push_back(Vec3f(floor(pos[0]/dx+0.5),floor(pos[1]/dx+0.5),floor(pos[2]/dx+0.5)));
particlesMass.push_back(0.1); //Kg
particlesDensity.push_back(0);
particlesVolume.push_back(0);
particlesDeformation.push_back(Eigen::Matrix3f::Identity()); //3x3 init with identity
plasticDeformationGradient.push_back(Eigen::Matrix3f::Identity());
elasticDeformationGradient.push_back(Eigen::Matrix3f::Identity());
}
}
}
ParticleToGrid();
ParticleVolumeDensity();
}
void FluidSim::set_liquid(float (*phi)(const Vec3f&)) {
//surface.reset_phi(phi, dx, Vec3f(0.5f*dx,0.5f*dx,0.5f*dx), ni, nj, nk);
//initialize particles
int seed = 0;
for(int k = 0; k < nk; ++k) for(int j = 0; j < nj; ++j) for(int i = 0; i < ni; ++i) {
Vec3f pos(i*dx,j*dx,k*dx);
float a = randhashf(seed++); float b = randhashf(seed++); float c = randhashf(seed++);
pos += dx * Vec3f(a,b,c);
if(phi(pos) <= -particle_radius) {
float solid_phi = interpolate_value(pos/dx, nodal_solid_phi);
if(solid_phi >= 0)
particles.push_back(pos);
}
}
}
FlowNoise2::
FlowNoise2(unsigned int seed, float spin_variation)
: Noise2(seed)
{
seed+=n;
for(unsigned int i=0; i<n; ++i){
original_basis[i]=basis[i];
spin_rate[i]=2.0f*(float)M_PI*randhashf(seed++, 1-0.5f*spin_variation, 1+0.5f*spin_variation);
}
}
static Vec<N,float> sample_sphere(unsigned int &seed)
{
Vec<N,float> v;
float m2;
do{
for(unsigned int i=0; i<N; ++i){
v[i]=randhashf(seed++,-1,1);
}
m2=mag2(v);
}while(m2>1 || m2==0);
return v/std::sqrt(m2);
}