Polygon Map Test Data

gistfile1.txt

Border of Polygon
-115.103760,50.958427,0.0 
-115.982666,51.103522,0.0 
-116.290283,51.323747,0.0 
-116.323242,51.563412,0.0 
-115.982666,51.638476,0.0 
-115.576172,51.549751,0.0 
-114.895020,51.337476,0.0 
-114.763184,51.013755,0.0 
-115.081787,50.958427,0.0 

Inside Polygon
-114.927979,51.096623,0.0 
-116.147461,51.467697,0.0 
-116.037598,51.261915,0.0 
-115.762939,51.158677,0.0 
-115.477295,51.131108,0.0 
-115.202637,51.330612,0.0 
-115.960693,51.577070,0.0

Border of Square
-115.795898,51.412912,0.0 
-115.136719,51.426614,0.0 
-115.092773,50.750359,0.0 
-115.751953,50.764259,0.0 
-115.806885,51.406059,0.0 

Inside Square
-115.708008,51.344339,0.0 
-115.290527,51.330612,0.0 
-115.213623,50.819818,0.0 
-115.653076,50.854509,0.0 

public bool IsPointInPolygon( Point p, Point[] polygon )
{
    double minX = polygon[ 0 ].X;
    double maxX = polygon[ 0 ].X;
    double minY = polygon[ 0 ].Y;
    double maxY = polygon[ 0 ].Y;
    for ( int i = 1 ; i < polygon.Length ; i++ )
    {
        Point q = polygon[ i ];
        minX = Math.Min( q.X, minX );
        maxX = Math.Max( q.X, maxX );
        minY = Math.Min( q.Y, minY );
        maxY = Math.Max( q.Y, maxY );
    }

    if ( p.X < minX || p.X > maxX || p.Y < minY || p.Y > maxY )
    {
        return false;
    }

    // http://www.ecse.rpi.edu/Homepages/wrf/Research/Short_Notes/pnpoly.html
    bool inside = false;
    for ( int i = 0, j = polygon.Length - 1 ; i < polygon.Length ; j = i++ )
    {
        if ( ( polygon[ i ].Y > p.Y ) != ( polygon[ j ].Y > p.Y ) &&
             p.X < ( polygon[ j ].X - polygon[ i ].X ) * ( p.Y - polygon[ i ].Y ) / ( polygon[ j ].Y - polygon[ i ].Y ) + polygon[ i ].X )
        {
            inside = !inside;
        }
    }

    return inside;
}