nodePtr leftRotation(nodePtr t)
{
nodePtr t2 = t->right;
t->right = t2->left;
t2->left = t;
t2 = fixN(t2);
return t2;
}
bool poly::giftwrap(){
if (surface.size() != 0)
surface.clear();
// sort by x coordinate
sortPoints(0);
// first points is minimum x
point p1 = points[0]; point* p1_ptr = &points[0];
// 2nd point is found by 2d giftwrap in xy plane
double maxDot = -1.;
point p2; point* p2_ptr;
for (int i=1;i<points.size();i++){
point delta = points[i] - p1;
delta.setX(2,0.);
delta.makeUnit();
double dDot = delta * point(0,1,0);
std::cout << delta << " * " << points[i] << " : " << dDot << std::endl;
if (maxDot < dDot){
maxDot = dDot;
p2 = points[i];
p2_ptr = &points[i];
}
else if (dDot == maxDot)
if ( (points[i] - p1).mag() < p2.mag()){
maxDot = dDot;
p2 = points[i];
p2_ptr = &points[i];
}
}
std::cout << p1 << " " << p2 << std::endl;
// project into plane defined by edge
// between the first two points
point dp = p2 - p1;
dp.makeUnit();
// origin in projected space
point p0 = p1 - dp * (dp*p1);
std::vector<point> pp;
for (int i=1;i<points.size();i++)
if (points[i] != p2)
pp.push_back(points[i] - dp * (dp*points[i]) - p0);
// find all possible pairs of points
std::vector<point> ppairs1;
std::vector<point> ppairs2;
for (int i=0;i<pp.size();i++)
for (int j=i+1;j<pp.size();j++){
ppairs1.push_back(pp[i]);
ppairs2.push_back(pp[j]);
}
pp.clear();
// find the two points in this space
// with the largest opening angle
point pp1, pp2;
double minDot = 2.;
for (int i=0;i<ppairs1.size();i++){
double dDot = (ppairs1[i]*ppairs2[i])/(ppairs1[i].mag()*ppairs2[i].mag());
if (dDot < minDot){
minDot = dDot;
pp1 = ppairs1[i];
pp2 = ppairs2[i];
}
else if (dDot == minDot)
if ( (ppairs1[i]-ppairs2[i]).mag() < (pp1-pp2).mag()){
minDot = dDot;
pp1 = ppairs1[i];
pp2 = ppairs2[i];
}
}
ppairs1.clear();
ppairs2.clear();
// find the poitns in original space
// that match the points at large angles
// these are the first two triangles
for (int i=0;i<points.size();i++){
point mPP = points[i] - dp*(dp*points[i]) - p0;
if (mPP==pp1 || mPP==pp2)
surface.push_back(tri(*p1_ptr,*p2_ptr,points[i]));
}
if (!markEdges())
return false;
// for (int j=0;j<surface.size();j++)
// std::cout << "surface["<<j<< "] : " << surface[j] << std::endl;
// std::cout << std::endl;
while (isSurfaceOpen()){
edge mE;
point mP;
for (int i=0;i<surface.size();i++){
if (!surface[i].getUnconnected(mE, mP))
continue;
dp = mE(1) - mE(0);
dp.makeUnit();
p0 = mE(1) - dp*(dp*mE(1));
point mPP = mP - dp*(dp*mP) - p0;
mPP = -mPP/(mPP.mag());
std::vector<point> ppoints;
for (int j=0;j<points.size();j++){
if (surface[i].hasPoint(points[j]))
continue;
ppoints.push_back(points[j] - dp *(dp*points[j]) - p0);
}
double maxDot = -2.;
point nPP;
// find most colinear
for (int j=0;j<ppoints.size();j++){
double dDot = (ppoints[j]*mPP)/ppoints[j].mag();
if (dDot > maxDot){
maxDot = dDot;
nPP = ppoints[j];
}
// if there are planar points, take the closest one
else if (dDot == maxDot)
if ( ppoints[j].mag() < nPP.mag()){
maxDot = dDot;
nPP = ppoints[j];
}
}
ppoints.clear();
for (int j=0;j<points.size();j++)
if (nPP == points[j] - dp*(dp*points[j]) - p0)
surface.push_back(tri(mE(0),mE(1),points[j]));
// for (int j=0;j<surface.size();j++)
// std::cout << "surface["<<j<< "] : " << surface[j] << std::endl;
// std::cout << std::endl;
if (!markEdges()) {
return false;
//unmarkEdges();
//surface.pop_back();
//for (int j=0;j<surface.size();j++)
//std::cout << "surface["<<j<< "] : " << surface[j] << std::endl;
//std::cout << std::endl;
//continue;
}
break;
}
}
calcCenter();
fixN();
return true;
}
