You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
110 lines
3.3 KiB
Java
110 lines
3.3 KiB
Java
/*This is a Java Program to check whether a polygon contains another polygon or not. The class returns true if one polygon contains another, false otherwise.*/
|
|
|
|
//This is a java program to test whether a polygon is inside another polygon
|
|
class Point
|
|
{
|
|
int x, y;
|
|
|
|
Point()
|
|
{
|
|
}
|
|
|
|
Point(int p, int q)
|
|
{
|
|
x = p;
|
|
y = q;
|
|
}
|
|
}
|
|
|
|
public class Position_Point_WRT_Polygon
|
|
{
|
|
|
|
public static boolean onSegment(Point p, Point q, Point r)
|
|
{
|
|
if (q.x <= Math.max(p.x, r.x) && q.x >= Math.min(p.x, r.x)
|
|
&& q.y <= Math.max(p.y, r.y) && q.y >= Math.min(p.y, r.y))
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
public static int orientation(Point p, Point q, Point r)
|
|
{
|
|
int val = (q.y - p.y) * (r.x - q.x) - (q.x - p.x) * (r.y - q.y);
|
|
if (val == 0)
|
|
return 0;
|
|
return (val > 0) ? 1 : 2;
|
|
}
|
|
|
|
public static boolean doIntersect(Point p1, Point q1, Point p2, Point q2)
|
|
{
|
|
int o1 = orientation(p1, q1, p2);
|
|
int o2 = orientation(p1, q1, q2);
|
|
int o3 = orientation(p2, q2, p1);
|
|
int o4 = orientation(p2, q2, q1);
|
|
if (o1 != o2 && o3 != o4)
|
|
return true;
|
|
if (o1 == 0 && onSegment(p1, p2, q1))
|
|
return true;
|
|
if (o2 == 0 && onSegment(p1, q2, q1))
|
|
return true;
|
|
if (o3 == 0 && onSegment(p2, p1, q2))
|
|
return true;
|
|
if (o4 == 0 && onSegment(p2, q1, q2))
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
public static boolean isInside(Point polygon[], int n, Point p)
|
|
{
|
|
int INF = 10000;
|
|
if (n < 3)
|
|
return false;
|
|
Point extreme = new Point(INF, p.y);
|
|
int count = 0, i = 0;
|
|
do
|
|
{
|
|
int next = (i + 1) % n;
|
|
if (doIntersect(polygon[i], polygon[next], p, extreme))
|
|
{
|
|
if (orientation(polygon[i], p, polygon[next]) == 0)
|
|
return onSegment(polygon[i], p, polygon[next]);
|
|
count++;
|
|
}
|
|
i = next;
|
|
}
|
|
while (i != 0);
|
|
return (count & 1) == 1 ? true : false;
|
|
}
|
|
|
|
public static Boolean DoesPolygonContainPolygon(Point[] p1, Point[] p2)
|
|
{
|
|
Point p;
|
|
for (int i = 0; i < p2.length; i++)
|
|
{
|
|
p = new Point(p2[i].x, p2[i].y);
|
|
if (!isInside(p1, p1.length, p))
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
public static void main(String args[])
|
|
{
|
|
Point polygon1[] = { new Point(0, 0), new Point(10, 0),
|
|
new Point(10, 10), new Point(0, 10)
|
|
};
|
|
Point polygon2[] = { new Point(0, 0), new Point(15, 5), new Point(5, 0) };
|
|
Point polygon3[] = { new Point(0, 0), new Point(10, 0),
|
|
new Point(10, 10), new Point(0, 10), new Point(5, 5)
|
|
};
|
|
System.out.println("Polygon 1 contains Polygon 2 :"
|
|
+ DoesPolygonContainPolygon(polygon1, polygon2));
|
|
System.out.println("Polygon 3 contains Polygon 1 :"
|
|
+ DoesPolygonContainPolygon(polygon3, polygon1));
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
Polygon 1 contains Polygon 2 :false
|
|
Polygon 3 contains Polygon 1 :true |