Method emitParticles

SPlisHSPlasH/Emitter.cpp:89–227

}

void Emitter::emitParticles(std::vector <unsigned int> &reusedParticles, unsigned int &indexReuse, unsigned int &numEmittedParticles)
{
	TimeManager *tm = TimeManager::getCurrent();
	const Real t = tm->getTime();
	const Real timeStepSize = tm->getTimeStepSize();
	const Vector3r & emitDir = m_rotation.col(0);
	Vector3r emitVel = m_velocity * emitDir;
	Simulation *sim = Simulation::getCurrent();
	const Real radius = sim->getParticleRadius();
	const Real diam = static_cast<Real>(2.0)*radius;

	// shortly before the emitter starts, cleanup the emitter from particles
	if (t < m_emitStartTime || t > m_emitEndTime)
 		emitVel = emitDir * radius * 10 / 0.25;

	if (t >= m_emitStartTime - 0.25 && t <= m_emitEndTime)
	{
		// animate emitted particles
		const Vector3r & x0 = m_x;

		const Real animationMarginAhead = sim->getSupportRadius();
		const Vector3r size = getSize(static_cast<Real>(m_width), static_cast<Real>(m_height), m_type);
		const Vector3r halfSize = 0.5 * size;
		const Vector3r pos = x0 + static_cast<Real>(0.5) * animationMarginAhead * emitDir;

		const unsigned int nModels = sim->numberOfFluidModels();
		for (unsigned int m = 0; m < nModels; m++)
		{
			FluidModel *fm = sim->getFluidModel(m);
			const unsigned int numParticles = fm->numActiveParticles();
			#pragma omp parallel for schedule(static) default(shared)
			for (int i = 0; i < (int)numParticles; i++)
			{
				Vector3r &xi = fm->getPosition(i);
				if (inBox(xi, pos, m_rotation, halfSize))
				{
					fm->getVelocity(i) = emitVel;
					fm->getPosition(i) += timeStepSize * emitVel;
					fm->setParticleState(i, ParticleState::AnimatedByEmitter);
					fm->setObjectId(i, m_objectId);
				}
			}
		}
	}
	if (t < m_nextEmitTime || t > m_emitEndTime)
	{
		return;
	}

	const Vector3r axisHeight = m_rotation.col(1);
	const Vector3r axisWidth = m_rotation.col(2);
	
	const Real startX = -static_cast<Real>(0.5)*(m_width  - 1)*diam;
	const Real startZ = -static_cast<Real>(0.5)*(m_height - 1)*diam;

	// t-m_nextEmitTime is the time that has passed between the time the particle has been emitted and the current time step.
	// timeStepSize is added because emission happens at the end of the time step, but the particles are not animated anymore.
	const Real dt = t - m_nextEmitTime + timeStepSize;