void QChain::cutCircle(Circle circle) {
if (m_vertices.size() == 0) return;
circle.setCenter(circle.pos());
QPainterPath cr;
cr.addEllipse(circle.x - circle.r, circle.y - circle.r, 2 * circle.r,
2 * circle.r);
QPolygonF polygon;
for (QPointF p : m_vertices) polygon.append(p);
QPainterPath chain;
chain.addPolygon(polygon);
if (!chain.intersects(cr)) return;
chain = chain.subtracted(cr);
for (const QPolygonF &poly : chain.toSubpathPolygons()) {
std::vector<Vector2d> pts(poly.begin(), poly.end() - 1);
if (std::fabs(Geometry::area(pts.begin(), pts.end())) > 5.f) {
auto chain = std::make_unique<QChain>(world());
chain->setVertices(std::vector<QPointF>(pts.begin(), pts.end()));
chain->initializeLater(world());
world()->itemSet()->addBody(std::move(chain));
}
}
m_vertices.clear();
destroyLater();
}
Bullet::Bullet(Circle circle, Item *p) : QBody(p) {
setPosition(QPointF(circle.pos()));
setLinearDamping(0);
setBullet(true);
setBodyType(Dynamic);
auto fixture = std::make_unique<Box2DCircle>(this);
fixture->setShadowCaster(false);
fixture->setRadius(circle.radius());
fixture->setGroupIndex(-1);
addFixture(std::move(fixture));
}