Improve tessellation algorithm

Added new mesh class
Rewrite mesh algorithms to be less error prone
Make code more concise
Tried to add some documentation
Added half edge set

src/main/java/com/aaaaahhhhhhh/bananapuncher714/mesh/Polygon.java

@@ -0,0 +1,31 @@
+package com.aaaaahhhhhhh.bananapuncher714.mesh;
+
+import java.util.List;
+
+/**
+ * A list of points denoting the shape of the polygon. May contain self intersections,
+ * duplicate vertices, and overlapping edges.
+ * 
+ * @author BananaPuncher714
+ */
+public class Polygon {
+    protected List< Point > points;
+    
+    public Polygon( List< Point > points ) {
+        this.points = points;
+    }
+    
+    public List< Point > getPoints() {
+        return points;
+    }
+    
+    public double area() {
+        double area = 0;
+        for ( int i = 0; i < points.size(); ++i ) {
+            final Vector2d a = new Vector2d( points.get( i ) );
+            final Vector2d b = new Vector2d( points.get( ( i + 1 ) % points.size() ) );
+            area += a.cross( b );
+        }
+        return Math.abs( area ) / 2.0;
+    }
+}