static int intersect_poylgon(RAY *Ray, POLYGON *Polyg, DBL *Depth)
{
DBL x, y, len;
VECTOR p, d;
/* Don't test degenerate polygons. */
if (Test_Flag(Polyg, DEGENERATE_FLAG))
{
return(false);
}
Increase_Counter(stats[Ray_Polygon_Tests]);
/* Transform the ray into the polygon space. */
MInvTransPoint(p, Ray->Initial, Polyg->Trans);
MInvTransDirection(d, Ray->Direction, Polyg->Trans);
VLength(len, d);
VInverseScaleEq(d, len);
/* Intersect ray with the plane in which the polygon lies. */
if (fabs(d[Z]) < ZERO_TOLERANCE)
{
return(false);
}
*Depth = -p[Z] / d[Z];
if ((*Depth < DEPTH_TOLERANCE) || (*Depth > Max_Distance))
{
return(false);
}
/* Does the intersection point lie inside the polygon? */
x = p[X] + *Depth * d[X];
y = p[Y] + *Depth * d[Y];
if (in_polygon(Polyg->Data->Number, Polyg->Data->Points, x, y))
{
Increase_Counter(stats[Ray_Polygon_Tests_Succeeded]);
*Depth /= len;
return (true);
}
else
{
return (false);
}
}
polygon poly_intersect(polygon &P, polygon &Q){
int m = Q.size(), n = P.size();
int a = 0, b = 0, aa = 0, ba = 0, inflag = 0;
polygon R;
while( (aa < n || ba < m) && aa < 2*n && ba < 2*m){
Point p1 = P[a], p2 = P[(a+1) % n], q1 = Q[b], q2 = Q[(b+1) % m];
Point A = p2 - p1, B = q2 - q1;
int cross = cmp(A ^ B), ha = turn(p2, q2, p1), hb = turn(q2, p2, q1);
if(cross == 0 && turn(p1, q1, p2) == 0 && cmp(A * B) < 0){
if(between(p1, q1, p2)) R.push_back(q1);
if(between(p1, q2, p2)) R.push_back(q2);
if(between(q1, p1, q2)) R.push_back(p1);
if(between(q1, p2, q2)) R.push_back(p2);
if(R.size() < 2) return polygon();
inflag = 1; break;
}else if(cross != 0 && seg_intersect(p1, p2, q1, q2)) {
if(inflag == 0) aa = ba = 0;
R.push_back(intersection(p1, p2, q1, q2));
inflag = (hb > 0) ? 1 : -1;
}
if(cross == 0 && hb < 0 && ha < 0) return R;
bool t = cross == 0 && hb == 0 && ha == 0;
if(t ? (inflag == 1) : (cross >= 0) ? (ha <= 0) : (hb > 0)){
if(inflag == -1) R.push_back(q2);
ba++; b++; b %= m;
}else{
if(inflag == 1) R.push_back(p2);
aa++; a++; a %= n;
}
}
if(inflag == 0){
if (in_polygon(P[0], Q)) return P;
if (in_polygon(Q[0], P)) return Q;
}
R.erase(unique(R.begin(), R.end()), R.end());
if(R.size() > 1 && R.front() == R.back()) R.pop_back();
return R;
}
bool Polygon::Intersect(const BasicRay& ray, DBL *Depth, TraceThreadData *Thread) const
{
DBL x, y, len;
Vector3d p, d;
/* Don't test degenerate polygons. */
if (Test_Flag(this, DEGENERATE_FLAG))
return(false);
Thread->Stats()[Ray_Polygon_Tests]++;
/* Transform the ray into the polygon space. */
MInvTransPoint(p, ray.Origin, Trans);
MInvTransDirection(d, ray.Direction, Trans);
len = d.length();
d /= len;
/* Intersect ray with the plane in which the polygon lies. */
if (fabs(d[Z]) < ZERO_TOLERANCE)
return(false);
*Depth = -p[Z] / d[Z];
if ((*Depth < DEPTH_TOLERANCE) || (*Depth > MAX_DISTANCE))
return(false);
/* Does the intersection point lie inside the polygon? */
x = p[X] + *Depth * d[X];
y = p[Y] + *Depth * d[Y];
if (in_polygon(Data->Number, Data->Points, x, y))
{
Thread->Stats()[Ray_Polygon_Tests_Succeeded]++;
*Depth /= len;
return (true);
}
else
return (false);
}
int main(int argc, char *argv[])
{
srand(time(NULL));
if (argc != 6)
{
std::cout << usage << std::endl;
return -1;
}
int count = atoi(argv[1]);
double min = atof(argv[2]);
double max = atof(argv[3]);
std::ofstream file(argv[4], std::ofstream::out);
bool integer = false;
if (strcmp(argv[5], "double") == 0)
integer = false;
else if (strcmp(argv[5], "int") == 0)
integer = true;
point *ps = new point[count];
random_points(ps, count, min, max, integer);
space_partition(ps, count);
double real_min = 999999;
double real_max = -999999;
for (int i = 0; i < count; i++)
{
real_max = ps[i].x > real_max ? ps[i].x : real_max;
real_max = ps[i].y > real_max ? ps[i].y : real_max;
real_max = ps[i].x < real_min ? ps[i].x : real_min;
real_max = ps[i].y < real_min ? ps[i].y : real_min;
}
point start;
point end;
do
{
random_points(&start, 1, real_min, real_max, integer);
} while (!in_polygon(start, ps, count));
do
{
random_points(&end, 1, real_min, real_max, integer);
} while (!in_polygon(end, ps, count));
if (integer)
{
file << (int)round(start.x) << " " << (int)round(start.y) << " "
<< (int)round(end.x) << " " << (int)round(end.y) << std::endl;
file << count << std::endl;
for (int i = 0; i < count; i++)
file << (int)round(ps[i].x) << " " << (int)round(ps[i].y) << std::endl;
}
else
{
file << start.x << " " << start.y << " " << end.x << " " << end.y << std::endl;
file << count << std::endl;
for (int i = 0; i < count; i++)
file << ps[i].x << " " << ps[i].y << std::endl;
}
delete[] ps;
return 0;
}
//merging of 2 convex hulls
std::vector<Point2D> merge(std::vector<Point2D> set1, std::vector<Point2D> set2)
{
Point2Df p;
std::vector<Point2D> sum;
int is_line1 = is_line(set1);
int is_line2 = is_line(set2);
if(!is_line1)
{
for(int i = 0; i < set1.size() - 2; i++)
{
if(is_left(set1[i], set1[i + 1], set1[i + 2]) != 0)
{
p = centroid(set1[i], set1[i + 1], set1[i + 2]);
break;
}
}
}
else if(!is_line2)
{
for(int i = 0; i < set2.size() - 2; i++)
{
if(is_left(set2[i], set2[i + 1], set2[i + 2]) != 0)
{
p = centroid(set2[i], set2[i + 1], set2[i + 2]);
break;
}
}
}
if(!is_line1 && !is_line2)// 2 polygons
{
if(in_polygon(set2, p) != 0)
{
sum = merge_polygons(set1, set2, p);
return graham_scan(sum);
}
else
{
std::vector<Point2D> clean_set2;
clean_set2 = delete_chain(set2, p);
sum = merge_polygons(set1, clean_set2, p);
return graham_scan(sum);
}
}
else if (!is_line1 && is_line2)//polygon with centroid p and line
{
std::vector<Point2D> clean_set2;
/*
clean_set2 = delete_chain(set2, p);
sum = merge_polygons(set1, clean_set2, p);
*/
if(angle_compare(p, (Point2Df)set2[0], (Point2Df)set2[set2.size() - 1]))
{
clean_set2.push_back(set2[0]);
clean_set2.push_back(set2[set2.size() - 1]);
}
else
{
clean_set2.push_back(set2[set2.size() - 1]);
clean_set2.push_back(set2[0]);
}
sum = merge_polygons(set1, clean_set2, p);
return graham_scan(sum);
}
else if(is_line1 && !is_line2)
{
std::vector<Point2D> clean_set1;
/*
clean_set1 = delete_chain(set1, p);
sum = merge_polygons(clean_set1, set2, p);
*/
if(angle_compare(p, (Point2Df)set1[0], (Point2Df)set1[set1.size() - 1]))
{
clean_set1.push_back(set1[0]);
clean_set1.push_back(set1[set1.size() - 1]);
}
else
{
clean_set1.push_back(set1[set1.size() - 1]);
clean_set1.push_back(set1[0]);
}
sum = merge_polygons(clean_set1, set2, p);
return graham_scan(sum);
}
else // if(is_line1 && is_line2)
{
std::vector<Point2D> clean_set1;
clean_set1.push_back(set1[0]);
clean_set1.push_back(set1[set1.size() - 1]);
clean_set1.push_back(set2[0]);
clean_set1.push_back(set2[set2.size() - 1]);
return get_hull(clean_set1);
}
}