Point inside Polygon check
I want to know how I could make the method look prettier, and have better 'coding practices' though  



avoid single letter variable if they aren't iterator variables. If you or Sam the maintainer needs to come back to this method in a few months, neither you nor Sam will grasp at first glance what the variables are about.  
avoid shortening of method names. polyCheck does not tell anything about what the method tries to do. A name like IsInPolygon would be better. With a more OO approach by adding a Polygon class having a method Contains(Vector2) it would be more clear.  

public class Polygon
{
    public Vector2[] Vertices { get; private set; }
    public Polygon(Vector2[] vertices)
    {
        Vertices = vertices;
    }
    public bool ContainsVector(Vector2 vector)
    {
        // do the magic
        return true;
    }
}  

always use braces {} although they are optional for single lined for's. This will help you to make your code less error prone.  
let your variables and operators have some space to breathe. This  

c^=p[i].y&gt;v.y^p[j].y&gt;v.y&amp;&amp;v.x&lt;(p[j].x-p[i].x)*(v.y-p[i].y)/(p[j].y-p[i].y)+p[i].x;


is just not readable.