Method updateTimeStepSizeCFL

SPlisHSPlasH/Simulation.cpp:415–493

}

void Simulation::updateTimeStepSizeCFL()
{
	const Real radius = m_particleRadius;
	Real h = TimeManager::getCurrent()->getTimeStepSize();
	Simulation *sim = Simulation::getCurrent();
	const unsigned int nBoundaries = sim->numberOfBoundaryModels();

	// Approximate max. position change due to current velocities
	Real maxVel = 0.0;
	const Real diameter = static_cast<Real>(2.0)*radius;

	// fluid particles
	for (unsigned int fluidModelIndex = 0; fluidModelIndex < numberOfFluidModels(); fluidModelIndex++)
	{
		FluidModel *fm = getFluidModel(fluidModelIndex);
		const unsigned int numParticles = fm->numActiveParticles();
		for (unsigned int i = 0; i < numParticles; i++)
		{
			const Vector3r &vel = fm->getVelocity(i);
			const Vector3r &accel = fm->getAcceleration(i);
			const Real velMag = (vel + accel*h).squaredNorm();
			if (velMag > maxVel)
				maxVel = velMag;
		}
	}

	// boundary particles
	if (getBoundaryHandlingMethod() == BoundaryHandlingMethods::Akinci2012)
	{
		for (unsigned int i = 0; i < numberOfBoundaryModels(); i++)
		{
			BoundaryModel_Akinci2012 *bm = static_cast<BoundaryModel_Akinci2012*>(getBoundaryModel(i));
			if (bm->getRigidBodyObject()->isDynamic() || bm->getRigidBodyObject()->isAnimated())
			{
				for (unsigned int j = 0; j < bm->numberOfParticles(); j++)
				{
					const Vector3r &vel = bm->getVelocity(j);
					const Real velMag = vel.squaredNorm();
					if (velMag > maxVel)
						maxVel = velMag;
				}
			}
		}
	}
	else if (sim->getBoundaryHandlingMethod() == BoundaryHandlingMethods::Koschier2017)
	{
		for (unsigned int boundaryModelIndex = 0; boundaryModelIndex < numberOfBoundaryModels(); boundaryModelIndex++)
		{
			BoundaryModel_Koschier2017 *bm = static_cast<BoundaryModel_Koschier2017*>(getBoundaryModel(boundaryModelIndex));
			if (bm->getRigidBodyObject()->isDynamic() || bm->getRigidBodyObject()->isAnimated())
			{
				maxVel = std::max(maxVel, bm->getMaxVel());
			}
		}
	}
	else if (sim->getBoundaryHandlingMethod() == BoundaryHandlingMethods::Bender2019)
	{
		for (unsigned int boundaryModelIndex = 0; boundaryModelIndex < numberOfBoundaryModels(); boundaryModelIndex++)