Vector class

src/main/java/de/oshgnacknak/gruphi/Node.java

@@ -5,23 +5,23 @@ import java.awt.geom.Point2D;
 
 class Node {
 
-    public static final double RADIUS = 10;
+    public static final double RADIUS = 12;
 
     public static final Color COLOR = Color.WHITE;
 
-    Point2D.Double pos;
+    Vector pos;
 
     double radius;
 
     Color color;
 
     Node(double x, double y) {
-       this.pos = new Point2D.Double(x, y);
+       this.pos = new Vector(x, y);
        this.radius = RADIUS;
        this.color = COLOR;
     }
 
     boolean inside(double x, double y) {
-        return pos.distance(x, y) <= radius;
+        return pos.dist(x, y) <= radius;
     }
 }

src/main/java/de/oshgnacknak/gruphi/Vector.java

@@ -0,0 +1,64 @@
+package de.oshgnacknak.gruphi;
+
+public class Vector {
+
+    double x, y;
+
+    public Vector(double x, double y) {
+        this.x = x;
+        this.y = y;
+    }
+
+    Vector copy() {
+        return new Vector(x, y);
+    }
+
+    Vector add(Vector v) {
+        x += v.x;
+        y += v.y;
+        return this;
+    }
+
+    public Vector sub(Vector v) {
+        x -= v.x;
+        y -= v.y;
+        return this;
+    }
+
+    Vector mul(double d) {
+        x *= d;
+        y *= d;
+        return this;
+    }
+
+    double dot(Vector v) {
+        return x*v.x + y*v.y;
+    }
+
+    double mag() {
+        return Math.sqrt(dot(this));
+    }
+
+    Vector norm() {
+        return mul(1 / mag());
+    }
+
+    Vector setMag(double mag) {
+        return mul(mag/this.mag());
+    }
+
+    double dist(Vector v) {
+        return dist(v.x, v.y);
+    }
+
+    double dist(double x, double y) {
+        var dx = this.x - x;
+        var dy = this.y - y;
+        return Math.sqrt(dx*dx + dy*dy);
+    }
+
+
+    double angle() {
+        return Math.atan2(y, x);
+    }
+}