void StepSW::_populate_island(BodySW* p_body,BodySW** p_island,ConstraintSW **p_constraint_island) {
p_body->set_island_step(_step);
p_body->set_island_next(*p_island);
*p_island=p_body;
for(Map<ConstraintSW*,int>::Element *E=p_body->get_constraint_map().front();E;E=E->next()) {
ConstraintSW *c=(ConstraintSW*)E->key();
if (c->get_island_step()==_step)
continue; //already processed
c->set_island_step(_step);
c->set_island_next(*p_constraint_island);
*p_constraint_island=c;
for(int i=0;i<c->get_body_count();i++) {
if (i==E->get())
continue;
BodySW *b = c->get_body_ptr()[i];
if (b->get_island_step()==_step || b->get_mode()==PhysicsServer::BODY_MODE_STATIC)
continue; //no go
_populate_island(c->get_body_ptr()[i],p_island,p_constraint_island);
}
}
}
void StepSW::step(SpaceSW* p_space,float p_delta,int p_iterations) {
p_space->lock(); // can't access space during this
p_space->setup(); //update inertias, etc
const SelfList<BodySW>::List * body_list = &p_space->get_active_body_list();
/* INTEGRATE FORCES */
int active_count=0;
const SelfList<BodySW>*b = body_list->first();
while(b) {
b->self()->integrate_forces(p_delta);
b=b->next();
active_count++;
}
/* GENERATE CONSTRAINT ISLANDS */
BodySW *island_list=NULL;
ConstraintSW *constraint_island_list=NULL;
b = body_list->first();
int island_count=0;
while(b) {
BodySW *body = b->self();
if (body->get_island_step()!=_step) {
BodySW *island=NULL;
ConstraintSW *constraint_island=NULL;
_populate_island(body,&island,&constraint_island);
island->set_island_list_next(island_list);
island_list=island;
if (constraint_island) {
constraint_island->set_island_list_next(constraint_island_list);
constraint_island_list=constraint_island;
island_count++;
}
}
b=b->next();
}
const SelfList<AreaSW>::List &aml = p_space->get_moved_area_list();
while(aml.first()) {
for(const Set<ConstraintSW*>::Element *E=aml.first()->self()->get_constraints().front();E;E=E->next()) {
ConstraintSW*c=E->get();
if (c->get_island_step()==_step)
continue;
c->set_island_step(_step);
c->set_island_next(NULL);
c->set_island_list_next(constraint_island_list);
constraint_island_list=c;
}
p_space->area_remove_from_moved_list((SelfList<AreaSW>*)aml.first()); //faster to remove here
}
// print_line("island count: "+itos(island_count)+" active count: "+itos(active_count));
/* SETUP CONSTRAINT ISLANDS */
{
ConstraintSW *ci=constraint_island_list;
while(ci) {
_setup_island(ci,p_delta);
ci=ci->get_island_list_next();
}
}
/* SOLVE CONSTRAINT ISLANDS */
{
ConstraintSW *ci=constraint_island_list;
while(ci) {
//iterating each island separatedly improves cache efficiency
_solve_island(ci,p_iterations,p_delta);
ci=ci->get_island_list_next();
}
}
/* INTEGRATE VELOCITIES */
b = body_list->first();
while(b) {
b->self()->integrate_velocities(p_delta);
b=b->next();
}
/* SLEEP / WAKE UP ISLANDS */
{
BodySW *bi=island_list;
while(bi) {
_check_suspend(bi,p_delta);
bi=bi->get_island_list_next();
}
}
p_space->update();
p_space->unlock();
_step++;
}