Method computeDensities

SPlisHSPlasH/TimeStep.cpp:58–116

#ifdef USE_AVX

void TimeStep::computeDensities(const unsigned int fluidModelIndex)
{
	Simulation *sim = Simulation::getCurrent();
	FluidModel *model = sim->getFluidModel(fluidModelIndex);
	const Real density0 = model->getDensity0();
	const unsigned int numParticles = model->numActiveParticles();
	const unsigned int nFluids = sim->numberOfFluidModels();
	const unsigned int nBoundaries = sim->numberOfBoundaryModels();

	#pragma omp parallel default(shared)
	{
		#pragma omp for schedule(static)  
		for (int i = 0; i < (int) numParticles; i++)
		{
			const Vector3r &xi = model->getPosition(i);
			Real &density = model->getDensity(i);
			density = model->getVolume(i) * CubicKernel_AVX::W_zero();

			Scalarf8 density_avx(0.0f);
			Vector3f8 xi_avx(xi);

			//////////////////////////////////////////////////////////////////////////
			// Fluid
			//////////////////////////////////////////////////////////////////////////
			forall_fluid_neighbors_avx(
				const Scalarf8 Vj_avx = convert_zero(fm_neighbor->getVolume(0), count);
				density_avx += Vj_avx * CubicKernel_AVX::W(xi_avx - xj_avx);
			);

			//////////////////////////////////////////////////////////////////////////
			// Boundary
			//////////////////////////////////////////////////////////////////////////
			if (sim->getBoundaryHandlingMethod() == BoundaryHandlingMethods::Akinci2012)
			{
				forall_boundary_neighbors_avx(
					const Scalarf8 V_avx = convert_zero(&sim->getNeighborList(fluidModelIndex, pid, i)[j], &bm_neighbor->getVolume(0), count);
					density_avx += V_avx * CubicKernel_AVX::W(xi_avx - xj_avx);
				);
				density += density_avx.reduce();
			}
			else if (sim->getBoundaryHandlingMethod() == BoundaryHandlingMethods::Koschier2017)
			{
				density += density_avx.reduce();
				forall_density_maps(
					density += rho;
				);
			}
			else   // Bender2019
			{
				density += density_avx.reduce();
				forall_volume_maps(
					density += Vj * sim->W(xi - xj);
				);
			}

			density *= density0;
		}
	}