//------------------------------------------------------------
void particle::update(){
vel = vel + frc;
pos = pos + vel;
age++;
if( age > lifespan ){
dead = true;
}
resetForce();
}
void Entity::integrate(float deltaTime) {
//Integration phase
// dv = (Force /mass) * dt
velocity_ += (md_.inv_mass * forces_) * deltaTime;
prevPosition_ = position_;
// dx = V * dt
position_ += velocity_ * deltaTime;
if(collider_) collider_->setPosition(position_);
//Zero out the vector containing all the forces applied,
//so it can be used again for the next frame
resetForce();
}
void Physics::step( real_t dt )
{
// TODO step the world forward by dt. Need to detect collisions, apply
// forces, and integrate positions and orientations.
//
// Note: put RK4 here, not in any of the physics bodies
//
// Must use the functions that you implemented
//
// Note, when you change the position/orientation of a physics object,
// change the position/orientation of the graphical object that represents
// it
Derivative initial;
Derivative k1, k2, k3, k4;
Vector3 sumAngles;
for(unsigned int i = 0; i < spheres.size(); i++){
initial.velocity = spheres[i]->velocity;
initial.angular_velocity = spheres[i]->angular_velocity;
initial.position = spheres[i]->position;
initial.orientation = spheres[i]->orientation;
initial.angle = Vector3(0,0,0);
resetForce(*spheres[i]);
/****************************RK4**************************************/
/* k1 */
setPosition(initial, k1, initial, 0);
updateState(*spheres[i], k1);
spheres[i]->apply_force(gravity, Vector3(0,0,0));
for(unsigned int j = 0; j < springs.size(); j++){
if(springs[j]->body1->id == spheres[i]->id || springs[j]->body2->id == spheres[i]->id)
springs[j]->step(dt);
}
Evaluate(k1, *spheres[i], dt);
resetForce(*spheres[i]);
/* k2 */
setPosition(k1, k2, initial, dt/2);
updateState(*spheres[i], k2);
spheres[i]->apply_force(gravity, Vector3(0,0,0));
for(unsigned int j = 0; j < springs.size(); j++){
if(springs[j]->body1->id == spheres[i]->id || springs[j]->body2->id == spheres[i]->id)
springs[j]->step(dt/2);
}
Evaluate(k2, *spheres[i], dt);
resetForce(*spheres[i]);
/* k3 */
setPosition(k2, k3, initial, dt/2);
updateState(*spheres[i], k3);
spheres[i]->apply_force(gravity, Vector3(0,0,0));
for(unsigned int j = 0; j < springs.size(); j++){
if(springs[j]->body1->id == spheres[i]->id || springs[j]->body2->id == spheres[i]->id)
springs[j]->step(dt/2);
}
Evaluate(k3, *spheres[i], dt);
resetForce(*spheres[i]);
/* k4 */
setPosition(k3, k4, initial, dt);
updateState(*spheres[i], k4);
spheres[i]->apply_force(gravity, Vector3(0,0,0));
for(unsigned int j = 0; j < springs.size(); j++){
if(springs[j]->body1->id == spheres[i]->id || springs[j]->body2->id == spheres[i]->id)
springs[j]->step(dt);
}
Evaluate(k4, *spheres[i], dt);
resetForce(*spheres[i]);
/***************udpate position and orientation after RK4***************/
spheres[i]->position = initial.position + 1.0 / 6.0 * (k1.position + 2.0 * (k2.position + k3.position) + k4.position);
spheres[i]->velocity = initial.velocity + 1.0 / 6.0 * (k1.velocity + 2.0 * (k2.velocity + k3.velocity) + k4.velocity);
spheres[i]->angular_velocity = initial.angular_velocity + 1.0 / 6.0 * (k1.angular_velocity + 2.0 * (k2.angular_velocity + k3.angular_velocity) + k4.angular_velocity);
sumAngles = 1.0 / 6.0 * (k1.angle + 2.0 * (k2.angle + k3.angle) + k4.angle);
if(sumAngles != Vector3(0,0,0)){
spheres[i]->orientation = initial.orientation * Quaternion(normalize(sumAngles), length(sumAngles));
}
else{
spheres[i]->orientation = initial.orientation;
}
spheres[i]->sphere->position = spheres[i]->position;
spheres[i]->sphere->orientation = spheres[i]->orientation;
/*******collision detection************/
for(unsigned int j = 0; j < spheres.size(); j++){
if(spheres[i]->id != spheres[j]->id){
collides(*spheres[i], *spheres[j], collision_damping);
}
}
for(unsigned int j = 0; j < triangles.size(); j++){
collides(*spheres[i], *triangles[j], collision_damping);
}
for(unsigned int j = 0; j < planes.size(); j++){
collides(*spheres[i], *planes[j], collision_damping);
}
}
}
void Particle::update(){
resetForce();
updateForce();
updatePos();
}
// -----------------------------------------------------------
void Particle::update(){
vel += acc;
vel *= (1.0-damping);
pos += vel;
resetForce();
}
static void resetForces(int number_of_stars, struct star* star_array)
{
for(int i = 0; i < number_of_stars; ++i){
resetForce(&star_array[i]);
}
}
void TriParticle::update(){
resetForce();
updateForce();
updatePos();
rot += rotVel;
}
