bool VglPlus::mergeTwolineSegmentOnALine(const vgl_line_segment_2d<double> & seg1,
const vgl_line_segment_2d<double> & seg2,
vgl_line_segment_2d<double> & merged_seg)
{
double cosVal = fabs(cos_angle(seg1.direction(), seg2.direction()));
if (cosVal < cos(5.0/180.0*vnl_math::pi)) {
return false;
}
double dis_max = -1.0;
vcl_vector<vgl_point_2d<double> > pts;
pts.push_back(seg1.point1());
pts.push_back(seg1.point2());
pts.push_back(seg2.point1());
pts.push_back(seg2.point2());
// loop all combination and choose the longest one
for (int i = 0; i<pts.size(); i++) {
for (int j = i+1; j<pts.size(); j++) {
double dis = vgl_distance(pts[i], pts[j]);
if (dis > dis_max) {
dis_max = dis;
merged_seg = vgl_line_segment_2d<double>(pts[i], pts[j]);
}
}
}
return true;
}
bool vgl_intersection(vgl_line_segment_2d<double> lineSegment0, vgl_line_segment_2d<double> lineSegment1, vgl_point_2d<double> &intersectionPoint)
{
vgl_point_3d<double> lineSegment03DP0(lineSegment0.point1().x(), lineSegment0.point1().y(), 0);
vgl_point_3d<double> lineSegment03DP1(lineSegment0.point2().x(), lineSegment0.point2().y(), 0);
vgl_line_segment_3d<double> lineSegment03D(lineSegment03DP0, lineSegment03DP1);
vgl_point_3d<double> lineSegment13DP0(lineSegment1.point1().x(), lineSegment1.point1().y(), 0);
vgl_point_3d<double> lineSegment13DP1(lineSegment1.point2().x(), lineSegment1.point2().y(), 0);
vgl_line_segment_3d<double> lineSegment13D(lineSegment13DP0, lineSegment13DP1);
vgl_point_3d<double> intersectionPoint3D;
bool isIntersect = vgl_intersection(lineSegment03D, lineSegment13D, intersectionPoint3D);
intersectionPoint.set(intersectionPoint3D.x(), intersectionPoint3D.y());
return isIntersect;
}
void VilDraw::draw_segment(vil_image_view<vxl_byte> &image,
const vgl_line_segment_2d<double> & seg,
const vcl_vector<vxl_byte> & colour,
int lineWidth)
{
assert(image.nplanes() == 3 || image.nplanes() == 1);
assert(colour.size() == 3);
vil_image_view<vxl_byte> rgb_image = image;
if (image.nplanes() == 1) {
image = VilUtil::gray_2_rgb(image);
}
VilAlgoPlus::fill_line(image, seg.point1(), seg.point2(), colour);
}
void VglPlus::parallelMove(const vgl_line_segment_2d<double> & initSeg, double distance,
vgl_line_segment_2d<double> & seg1, vgl_line_segment_2d<double> & seg2)
{
// CCW rotated
vgl_vector_2d<double> orthDir = rotated(initSeg.direction(), vnl_math::pi/2.0);
orthDir = normalize(orthDir);
vgl_point_2d<double> p1 = initSeg.point1();
vgl_point_2d<double> p2 = initSeg.point2();
vgl_vector_2d<double> dp = distance * orthDir;
vgl_point_2d<double> p3(p1.x() + dp.x(), p1.y() + dp.y());
vgl_point_2d<double> p4(p2.x() + dp.x(), p2.y() + dp.y());
seg1 = vgl_line_segment_2d<double>(p3, p4);
dp = -1.0 * dp;
vgl_point_2d<double> p5(p1.x() + dp.x(), p1.y() + dp.y());
vgl_point_2d<double> p6(p2.x() + dp.x(), p2.y() + dp.y());
seg2 = vgl_line_segment_2d<double>(p5, p6);
}
vcl_vector<vgl_point_2d<double> > VglPlus::intersection(const vgl_ellipse_2d<double> & ellipse, const vgl_line_segment_2d<double> & seg)
{
vgl_conic<double> conic = vgl_conic<double>(ellipse);
vcl_vector<vgl_point_2d<double> > intersections;
vgl_homg_line_2d<double> homg_line(vgl_homg_point_2d<double>(seg.point1()), vgl_homg_point_2d<double>(seg.point2()));
vcl_list<vgl_homg_point_2d<double> > pts = vgl_homg_operators_2d<double>::intersection(conic, homg_line);
for (vcl_list<vgl_homg_point_2d<double>>::iterator ite = pts.begin(); ite != pts.end(); ite++) {
if (ite->w() != 0.0) {
double x = ite->x()/ite->w();
double y = ite->y()/ite->w();
double dis = vgl_distance(vgl_point_2d<double>(x, y), seg);
if (dis < 1.0) {
intersections.push_back(vgl_point_2d<double>(x, y));
}
}
}
return intersections;
}
bool VglPlus::isLeftSide(const vgl_line_segment_2d<double> & seg, const vgl_point_2d<double> & p)
{
vgl_point_2d<double> b = seg.point1();
vgl_point_2d<double> a = seg.point2();
return ((b.x() - a.x())*(p.y() - a.y()) - (b.y() - a.y())*(p.x() - a.x())) > 0;
}