void StableWorld::SaveState()
{
ForEachDynamicBody(GetBodyList(), [](b2Body* body) {
auto d = GetBodyState(body);
const auto& t = body->GetTransform();
d->prev_p = d->curr_p;
d->curr_p = t.p;
d->prev_r = d->curr_r;
d->curr_r = t.q.GetAngle();
});
}
void StableWorld::RestoreState()
{
ForEachDynamicBody(GetBodyList(), [this](b2Body* body) {
auto d = GetBodyState(body);
if (!d->sprite)
return;
const Vec2f position(d->curr_p.x * ptm_, d->curr_p.y * ptm_);
d->sprite->set_position(position);
d->sprite->set_rotation(d->curr_r);
});
}
void StableWorld::Interpolate()
{
const float ratio = elapsed_ * kStepsPerMs;
ForEachDynamicBody(
GetBodyList(),
[this](b2Body* body, float ratio, float rest) {
if (!body->IsAwake())
return;
auto d = GetBodyState(body);
if (!d->sprite)
return;
const b2Vec2 v = ptm_ * (ratio * d->curr_p + rest * d->prev_p);
d->sprite->set_position(Vec2f(v.x, v.y));
d->sprite->set_rotation(ratio * d->curr_r + rest * d->prev_r);
},
ratio,
1.0f - ratio);
}
void StableWorld::DestroyBody(b2Body* body)
{
delete GetBodyState(body);
b2World::DestroyBody(body);
}
void Menu::Include(Control* c) {
scene_->Insert(c);
c->SetState(GetBodyState());
Reparent(c, this);
}