SolidBrush brush = new SolidBrush(Color.LightGreen); //цвет кисти
// Добавляем/удаляем точки
private void pictureBox_MouseClick(object sender, MouseEventArgs e)
{
my_point p = null;
foreach (my_point pp in points)
{
if (Math.Abs(pp.X - e.X) <= 3 && Math.Abs(pp.Y - e.Y) <= 3)
{
p = pp;
}
}
// если нажата левая кнопка мыши, то добавляем
if (e.Button == MouseButtons.Left)
{
my_point new_p = new my_point(e.X, e.Y);
points.Add(new_p);
g.FillEllipse(brush, new_p.X - 4, new_p.Y - 4, 8, 8);
pictureBox.Image = bmp;
return;
}
// иначе - удаляем
else
{
points.Remove(p);
redrawImage();
}
}
private my_point find_second_point(List <my_point> list, my_point fst_point)
{
my_point res = fst_point;
double min_deg = 180;
foreach (my_point p in list)
{
double deg = degree_between_edges(new edge(fst_point, new my_point(fst_point.X, fst_point.Y - 1)), new edge(fst_point, p));
if (deg < min_deg)
{
min_deg = deg;
res = p;
}
}
return(res);
}
// Определяет c какой стороны относительно направленного ребра лежит точка
// ed - ребро
// pt - точка
// 1 - слева, -1 - справа, 0 - на ребре
private int pos_rel_edge(edge ed, my_point pt)
{
double z = (ed.P2.Y - ed.P1.Y) * pt.X + (ed.P1.X - ed.P2.X) * pt.Y + (ed.P1.X * (ed.P1.Y - ed.P2.Y) + ed.P1.Y * (ed.P2.X - ed.P1.X));
if (z < 0)
{
return(-1);
}
else
if (z > 0)
{
return(1);
}
else
{
return(0);
}
}
private my_point find_first_point(List <my_point> list)
{
my_point res = list[0];
int x = pictureBox.Width, y = pictureBox.Height;
foreach (my_point p in list)
{
if (p.X < x)
{
x = p.X;
res = p;
}
else if (p.X == x)
{
if (p.Y > y)
{
y = p.Y;
res = p;
}
}
}
return(res);
}
public Vertex(my_point l)
{
x = l.X; y = l.Y;
}
public triad(my_point aa, my_point bb, my_point cc)
{
a = aa; b = bb; c = cc;
find_coord_and_radius();
find_dist_to_center();
}
public bool contains(my_point p)
{
return(p == P1 || p == P2);
}
public edge(my_point p1, my_point p2)
{
P1 = p1; P2 = p2;
}
private void draw_point(my_point p)
{
g.FillEllipse(new SolidBrush(Color.Black), p.X - 4, p.Y - 4, 8, 8);
}
private void butt_triangulator_Click(object sender, EventArgs e)
{
redrawImage();
living_edges = new List <edge>();
my_point fst_point = find_first_point(points);
draw_point(fst_point);
my_point sec_point = find_second_point(points, fst_point);
draw_point(sec_point);
pictureBox.Image = bmp;
living_edges.Add(new edge(fst_point, sec_point));
while (living_edges.Count() > 0)
{
edge living = living_edges[living_edges.Count() - 1];
living_edges.RemoveAt(living_edges.Count() - 1);
double radius = double.MaxValue;
my_point third_point = null;
foreach (my_point p in points)
{
draw_point(p);
if (pos_rel_edge(living, p) != -1) // Определяет c какой стороны относительно направленного ребра лежит точка
{
continue; //1 - слева, -1 - справа, 0 - на ребре
}
triad tr = new triad(living.start(), living.end(), p);
if (radius > tr.dist)
{
radius = tr.dist;
third_point = p;
}
}
draw_edge(living);
if (third_point != null)
{
edge ed = new edge(living.start(), third_point);
int ind = living_edges.FindIndex(new Predicate <edge>(ee => ee == new edge(ed.end(), ed.start())));
if (ind >= 0)
{
draw_edge(living_edges[ind]);
living_edges.RemoveAt(ind);
}
else
{
living_edges.Add(ed);
//draw_edge(ed);
}
ed = new edge(third_point, living.end());
ind = living_edges.FindIndex(new Predicate <edge>(ee => ee == new edge(ed.end(), ed.start())));
if (ind >= 0)
{
draw_edge(living_edges[ind]);
living_edges.RemoveAt(ind);
}
else
{
living_edges.Add(ed);
//draw_edge(ed);
}
}
}
}