void Robot::rotateTo(const cv::Point2f &new_dir)
{
cv::Point2f dir(sin(ori),cos(ori));
float cross = dir.x*new_dir.y-dir.y*new_dir.x;
float dot = new_dir.dot(dir);
dot = dot>1?1:(dot<-1?-1:dot);
float angle = acos(dot);
if(cross<0)
turnRight(angle*180/M_PI);
else
turnLeft(angle*180/M_PI);
}
ConvexPolygon ConvexPolygon::intersect(const ConvexPolygon& poly) const
{
ConvexPolygon result;
int a = 0;
int b = 0;
int aa = 0;
int ba = 0;
enum State {IN_A, IN_B, UNKNOWN};
State state = UNKNOWN;
bool firstPoint = true;
do {
const int a1 = (a + m_vertices.size() - 1) % m_vertices.size();
const int b1 = (b + poly.vertices().size() - 1) % poly.vertices().size();
const cv::Point2f vecA = m_vertices[a] - m_vertices[a1];
const cv::Point2f vecB = poly.vertices()[b] - poly.vertices()[b1];
const float cross = signedArea2(cv::Point2f(0, 0), vecA, vecB);
const float aHB = signedArea2(poly.vertices()[b1], poly.vertices()[b], m_vertices[a]);
const float bHA = signedArea2(m_vertices[a1], m_vertices[a], poly.vertices()[b]);
//std::cout << "cross=" << cross << ", aHB=" << aHB << ", bHA=" << bHA << std::endl;
std::vector<cv::Point2f> intersectionPoints;
LineSegment::IntersectResult intersectResult = LineSegment(m_vertices[a1], m_vertices[a]).intersect(LineSegment(poly.vertices()[b1], poly.vertices()[b]), intersectionPoints);
if (intersectResult == LineSegment::INTERESECTING) {
if (firstPoint && state == UNKNOWN) {
aa = 0;
ba = 0;
firstPoint = false;
}
if (aHB > 0) {
state = IN_A;
} else if (bHA > 0) {
state = IN_B;
}
assert(intersectionPoints.size() > 0);
result.addPoint(intersectionPoints[0]);
}
if ((intersectResult == LineSegment::COINCIDENT) && (intersectionPoints.size() > 0) && (vecA.dot(vecB) < 0)) {
result = ConvexPolygon(intersectionPoints);
return result;
}
if ((std::abs(cross) <= std::numeric_limits<float>::epsilon()) && (std::abs(aHB) <= std::numeric_limits<float>::epsilon()) && (std::abs(bHA) <= std::numeric_limits<float>::epsilon())) {
if (state == IN_A) {
ba++;
b = (b + 1) % poly.vertices().size();
} else {
aa++;
a = (a + 1) % m_vertices.size();
}
} else if ((std::abs(cross) <= std::numeric_limits<float>::epsilon()) && (aHB < 0) && (bHA < 0)) {
std::cout << "III" << std::endl;
result.clear();
return result;
} else if (cross >= 0) {
if (bHA > 0) {
if (state == IN_A) {
result.addPoint(m_vertices[a]);
}
aa++;
a = (a + 1) % m_vertices.size();
} else {
if (state == IN_B) {
result.addPoint(poly.vertices()[b]);
}
ba++;
b = (b + 1) % poly.vertices().size();
}
} else {
if (aHB > 0) {
if (state == IN_B) {
result.addPoint(poly.vertices()[b]);
}
ba++;
b = (b + 1) % poly.vertices().size();
} else {
if (state == IN_A) {
result.addPoint(m_vertices[a]);
}
aa++;
a = (a + 1) % m_vertices.size();
}
}
//std::cout << "a=" << a << ", b=" << b << ", aa=" << aa << ", ba=" << ba << ", state=" << state << std::endl;
} while (((aa < (int)m_vertices.size()) || (ba < (int)poly.vertices().size())) && (aa < 2 * (int)m_vertices.size()) && (ba < 2 * (int)poly.vertices().size()));
return result;
}
