void UniversalForce::apply(ParticleManager &pm) {
unsigned int count = pm.getSize();
std::vector<unsigned int> toErase;
bool mustErase = false;
for(int i = 0; i < count; ++i){
// -------------------------------------
// ----- calcul de la durée de vie -----
// -------------------------------------
if(pm.decreaseParticleLifetime(i) == true){
toErase.push_back(i);
mustErase = true;
}
// ---------------------
// ----- Répulsion -----
// ---------------------
glm::vec2 p1=pm.getParticlePosition(i);
for(int j = 0; j < count; ++j){
if(i != j){
glm::vec2 p2=pm.getParticlePosition(j);
glm::vec2 vect = p2 - p1;
float norm = glm::length(vect);
glm::vec2 force = glm::vec2(0.0);
// Répulsion
if(norm < m_fLInf - 0.04f){
force = m_fKRep*(1-(m_fLInf-0.04f)/glm::max(norm,0.0001f))*(vect);
}
// Sticky
if(norm > m_fLInf && norm < m_fLSup){
force = m_fKSticky*(1-m_fLInf/glm::max(norm,0.0001f))*(vect);
}
pm.addForce(i, force);
}
}
// Fin répulsion
// ----------------------------------------
// - Attraction vers le centre de l'écran -
// ----------------------------------------
glm::vec2 pos = pm.getParticlePosition(i);
glm::vec2 p2 = glm::vec2(0.,0.);
glm::vec2 vect = p2 - pos;
float norm = glm::length(vect);
glm::vec2 force = glm::vec2(0.0);
force = m_fConstK*(1-m_fConstL/glm::max(norm,0.0001f))*(vect);
pm.addForce(i, force);
// Fin attraction centre
// -----------------
// ----- Brake -----
// -----------------
glm::vec2 v1=pm.getParticleVelocity(i);
for(int j = 0; j < count; ++j){
if(i != j){
glm::vec2 v2 = pm.getParticleVelocity(j);
glm::vec2 p1 = pm.getParticlePosition(i);
glm::vec2 p2 = pm.getParticlePosition(j);
if(m_fDt > 0){
glm::vec2 force = glm::vec2(0.0, 0.0);
float norm = glm::length(p2-p1);
if(norm < m_fBrakeL){
force = m_fBrakeV*((v2-v1)/m_fDt);
}
// amortissement
if(m_fBrakeAmort > 0.0f){
glm::vec2 amortissment = glm::vec2(0.0);
Leapfrog::ParticleState actualState;
actualState.position = pm.getParticlePosition(i);
actualState.velocity = pm.getParticleVelocity(i);
Leapfrog::ParticleState nextState = Leapfrog::getNextState(i, pm, m_fDt);
if(m_fDt > 0.0){
glm::vec2 dV = (nextState.velocity - actualState.velocity) / m_fDt;
dV *= m_fBrakeAmort;
pm.addForce(i, -dV);
}
}
pm.addForce(i, force);
}
}
}
// fin Brake
}
// effacer les particules en fin de vie
if(mustErase){
for(unsigned int i = 0; i < toErase.size(); ++i){
pm.killParticle(i);
}
}
}
void ConstantForce::apply(ParticleManager &pm) {
unsigned int count = pm.getSize();
for(int i = 0; i < count; ++i){
pm.addForce(i, m_force);
}
}