bool intersects(segment& s) {
auto det1 = det(p, q, s.p);
auto det2 = det(p, q, s.q);
auto det3 = det(s.p, s.q, p);
auto det4 = det(s.p, s.q, q);
return (equals(det1, 0) && contains(s.p)) || (equals(det2, 0) && contains(s.q)) ||
(equals(det3, 0) && s.contains(p)) || (equals(det4, 0) && s.contains(q)) || (det1 * det2 < -EPS && det3 * det4 < -EPS);
}
void deal(double k, double a, segment &ref) {
if (fabs(k) < eps) {
if (a <= 0) ref.sset(-INF, INF);
else ref.sset(INF, -INF);
} else if (k > 0) {
ref.sset(a/k, INF);
} else {
ref.sset(-INF, a/k);
}
}
bool isIntersected(segment &s1, segment &s2)
{
double cp1 = cp(s1.p1, s1.p2, s2.p1), cp2 = cp(s1.p1, s1.p2, s2.p2);
double cp3 = cp(s2.p1, s2.p2, s1.p1), cp4 = cp(s2.p1, s2.p2, s1.p2);
if ((cp1 * cp2 < 0) && (cp3 * cp4) < 0) return true;
if (fabs(cp1) <= EPSILON && s1.contains(s2.p1)) return true;
if (fabs(cp2) <= EPSILON && s1.contains(s2.p2)) return true;
if (fabs(cp3) <= EPSILON && s2.contains(s1.p1)) return true;
if (fabs(cp4) <= EPSILON && s2.contains(s1.p2)) return true;
return false;
}
bool isIntersected(segment s1, segment s2)
{
line p = getLine(s1.p1, s1.p2), q = getLine(s2.p1, s2.p2);
if (fabs(p.a * q.b - q.a * p.b) < EPSILON)
{
if (fabs(cp(s1.p1, s1.p2, s2.p1)) < EPSILON)
return s1.contains(s2.p1) || s1.contains(s2.p2);
return false;
}
point pi = getIntersection(p, q);
return s1.contains(pi) && s2.contains(pi);
}
void test_segment(segment l1, segment l2)
{
cout << "segments intersection" << endl;
l1.s_print();
l2.s_print();
int ans = segments_intersection(l1, l2);
if(ans == 0)
cout << "no intersection" << endl;
else if(ans == 2)
cout << "one segment is 'on' another" << endl;
else if(ans == 1)
cout << "two segments intersection" << endl;
cout << endl;
}
vector<segment> manyQuad(segment cubic,int narcs)
/* Approximates cubic with narcs quadratics, where the first and last
* are trimmed by the manyArcTrim function.
*/
{
int i;
double piecelength,thispiecelength,abscissa[5],overhang;
double ordinate,lastordinate,startx;
double startslope,midslope,endslope;
double p,q,accel;
vector<segment> ret;
p=manyArcTrim(narcs);
q=p*p-p+0.25;
piecelength=cubic.length()/(narcs-2*p);
overhang=piecelength*p;
lastordinate=cubic.getstart().getz();
startx=cubic.getstart().getx();
for (i=0;i<narcs;i++)
{
abscissa[1]=i*piecelength+cubic.getstart().getx();
abscissa[0]=abscissa[1]-overhang;
abscissa[2]=abscissa[0]+piecelength/2;
abscissa[4]=abscissa[0]+piecelength;
abscissa[3]=abscissa[4]-overhang;
midslope=(cubic.slope(abscissa[3]-startx)+cubic.slope(abscissa[1]-startx))/2;
accel=(cubic.slope(abscissa[3]-startx)-cubic.slope(abscissa[1]-startx))/(abscissa[3]-abscissa[1]);
thispiecelength=piecelength;
if (i)
startslope=midslope-accel*piecelength/2;
else
{
startslope=midslope-accel*(abscissa[2]-abscissa[1]);
//cout<<"startslope="<<startslope<<", should be "<<cubic.startslope()<<endl;
thispiecelength-=overhang;
}
if (i<narcs-1)
endslope=midslope+accel*piecelength/2;
else
{
endslope=midslope+accel*(abscissa[3]-abscissa[2]);
//cout<<"endslope="<<endslope<<", should be "<<cubic.endslope()<<endl;
thispiecelength-=overhang;
}
ordinate=lastordinate+thispiecelength*(startslope+endslope)/2;
ret.push_back(segment(xyz(abscissa[i==0] ,0,lastordinate),
xyz(abscissa[4-(i==narcs-1)],0, ordinate)));
ret[i].setslope(START,startslope);
ret[i].setslope(END,endslope);
lastordinate=ordinate;
}
return ret;
}
void file_storage::read (record& _record, const segment _segment) const throw (storage_exception&) {
std::fstream file;
file.open(__fileName.c_str(), std::ios::binary|std::ios::in|std::ios::out);
if(!file.is_open())
throw file_open("Error: '" + __fileName + "' can not be opened!");
file.seekg(_segment.begin);
_record.read(file);
if ((_record.size() != _segment.size()) | (file.tellg() != _segment.end + (std::streamoff)1))
throw io_error("I/O error during read: '" + __fileName + "' may be corrupt or there may be a bug in the program!");
file.close();
}
void preProcess(Mat &image)
{
Mat im1;
cv::resize(image,im1,Size(640,480));
image=p.run(im1,20);
imshow("original1",image);
image=s.proces(image,1,300,20);
imshow("r",image);
}
void file_storage::append (const record& _record, segment& _segment) throw (storage_exception&) {
std::fstream file;
file.open(__fileName.c_str(), std::ios::binary|std::ios::in|std::ios::out|std::ios::ate);
if(!file.is_open())
throw file_open("Error: '" + __fileName + "' can not be opened!");
_segment.begin = file.tellp();
_record.write(file);
_segment.end = file.tellp() - (std::streamoff)1;
if (_record.size() != _segment.size())
throw io_error("I/O error during append: '" + __fileName + "' may be corrupt or there may be a bug in the program!");
file.close();
}
vector<double> offsets(segment &a,vector<segment> &q)
/* q is the piecewise quadratic approximation to a, the cubic corresponding
* to a spiralarc. Returns the offsets of the endpoints of the elements of q
* from a. These are used to offset points from the spiralarc along crossLines;
* the points must then be adjusted. The 0th and last numbers returned are 0.
*/
{
int i;
double along;
vector<double> ret;
for (i=0;i<q.size();i++)
{
along=q[i].getstart().getx()-q[0].getstart().getx();
ret.push_back(q[i].getstart().getz()-a.station(along).getz());
}
ret.push_back(0);
return ret;
}
bool operator<(const segment & a, const segment & b) {
double x = max(min(a.p.x, a.q.x), min(b.p.x, b.q.x));
return a.get_y(x) < b.get_y(x) - eps;
}
bool equalSegment(segment a, segment b) {
return zero(a.angle() - b.angle());
}
bool cmpSegment(segment a, segment b) {
if (!zero(a.angle() - b.angle())) return a.angle() < b.angle();
return (a.b - a.a) / (b.a - a.a) < 0;
}
void drawSegment(segment s) {
if (s.isDiameter()) {
glBegin(GL_LINE_STRIP);
glVertex2d(s.getStart().getX(), s.getStart().getY());
glVertex2d(s.getEnd().getX(), s.getEnd().getY());
glEnd();
return;
}
double middle = s.getCenter().arg() + M_PI;
complex startdef = (s.getStart() - s.getCenter())*unit(-middle);
complex enddef = (s.getEnd() - s.getCenter())*unit(-middle);
drawArc(s.getCenter(), s.getRadius(), middle + startdef.arg(), middle + enddef.arg());
}
segment transform::operator ()(segment s){
return s.mobius(c).rotate(th);
}
bool operator>(const segment& cur) {
double x = max(min(pointOne.x, pointTwo.x), min(cur.pointOne.x, cur.pointTwo.x));
return (gety(x) - eps) > cur.gety(x);
}
