Added a physics based aproach to optimizing the pose graph

Create unit tests for the scan matching algorithm

.gitignore

@@ -26,4 +26,7 @@ bin/
 .vscode/
 
 ### Mac OS ###
-.DS_Store
+.DS_Store
+
+map.txt
+processing-4.3/

.idea/inspectionProfiles/Project_Default.xml

@@ -0,0 +1,8 @@
+<component name="InspectionProjectProfileManager">
+  <profile version="1.0">
+    <option name="myName" value="Project Default" />
+    <inspection_tool class="JavadocDeclaration" enabled="true" level="WARNING" enabled_by_default="true">
+      <option name="ADDITIONAL_TAGS" value="brief" />
+    </inspection_tool>
+  </profile>
+</component>

.idea/libraries/core.xml

@@ -0,0 +1,9 @@
+<component name="libraryTable">
+  <library name="core">
+    <CLASSES>
+      <root url="jar://$PROJECT_DIR$/../../processing-4.3/core/library/core.jar!/" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES />
+  </library>
+</component>

.idea/libraries/ejml.xml

@@ -0,0 +1,13 @@
+<component name="libraryTable">
+  <library name="ejml">
+    <CLASSES>
+      <root url="file://$PROJECT_DIR$/lib/ejml-v0.42-libs" />
+    </CLASSES>
+    <JAVADOC />
+    <SOURCES>
+      <root url="file://$PROJECT_DIR$/lib/ejml-v0.42-libs" />
+    </SOURCES>
+    <jarDirectory url="file://$PROJECT_DIR$/lib/ejml-v0.42-libs" recursive="false" />
+    <jarDirectory url="file://$PROJECT_DIR$/lib/ejml-v0.42-libs" recursive="false" type="SOURCES" />
+  </library>
+</component>

.idea/misc.xml

@@ -1,4 +1,3 @@
-<?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="ProjectRootManager" version="2" languageLevel="JDK_20" default="true" project-jdk-name="openjdk-20" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/out" />

.idea/uiDesigner.xml

@@ -0,0 +1,124 @@
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+<project version="4">
+  <component name="Palette2">
+    <group name="Swing">
+      <item class="com.intellij.uiDesigner.HSpacer" tooltip-text="Horizontal Spacer" icon="/com/intellij/uiDesigner/icons/hspacer.svg" removable="false" auto-create-binding="false" can-attach-label="false">
+        <default-constraints vsize-policy="1" hsize-policy="6" anchor="0" fill="1" />
+      </item>
+      <item class="com.intellij.uiDesigner.VSpacer" tooltip-text="Vertical Spacer" icon="/com/intellij/uiDesigner/icons/vspacer.svg" removable="false" auto-create-binding="false" can-attach-label="false">
+        <default-constraints vsize-policy="6" hsize-policy="1" anchor="0" fill="2" />
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+      <item class="javax.swing.JPanel" icon="/com/intellij/uiDesigner/icons/panel.svg" removable="false" auto-create-binding="false" can-attach-label="false">
+        <default-constraints vsize-policy="3" hsize-policy="3" anchor="0" fill="3" />
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+        <default-constraints vsize-policy="0" hsize-policy="3" anchor="0" fill="1" />
+        <initial-values>
+          <property name="text" value="Button" />
+        </initial-values>
+      </item>
+      <item class="javax.swing.JRadioButton" icon="/com/intellij/uiDesigner/icons/radioButton.svg" removable="false" auto-create-binding="true" can-attach-label="false">
+        <default-constraints vsize-policy="0" hsize-policy="3" anchor="8" fill="0" />
+        <initial-values>
+          <property name="text" value="RadioButton" />
+        </initial-values>
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+        <default-constraints vsize-policy="0" hsize-policy="3" anchor="8" fill="0" />
+        <initial-values>
+          <property name="text" value="CheckBox" />
+        </initial-values>
+      </item>
+      <item class="javax.swing.JLabel" icon="/com/intellij/uiDesigner/icons/label.svg" removable="false" auto-create-binding="false" can-attach-label="false">
+        <default-constraints vsize-policy="0" hsize-policy="0" anchor="8" fill="0" />
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+          <property name="text" value="Label" />
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+      <item class="javax.swing.JFormattedTextField" icon="/com/intellij/uiDesigner/icons/formattedTextField.svg" removable="false" auto-create-binding="true" can-attach-label="true">
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+        <default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3" />
+      </item>
+      <item class="javax.swing.JProgressBar" icon="/com/intellij/uiDesigner/icons/progressbar.svg" removable="false" auto-create-binding="true" can-attach-label="false">
+        <default-constraints vsize-policy="0" hsize-policy="6" anchor="0" fill="1" />
+      </item>
+      <item class="javax.swing.JToolBar" icon="/com/intellij/uiDesigner/icons/toolbar.svg" removable="false" auto-create-binding="false" can-attach-label="false">
+        <default-constraints vsize-policy="0" hsize-policy="6" anchor="0" fill="1">
+          <preferred-size width="-1" height="20" />
+        </default-constraints>
+      </item>
+      <item class="javax.swing.JToolBar$Separator" icon="/com/intellij/uiDesigner/icons/toolbarSeparator.svg" removable="false" auto-create-binding="false" can-attach-label="false">
+        <default-constraints vsize-policy="0" hsize-policy="0" anchor="0" fill="1" />
+      </item>
+      <item class="javax.swing.JScrollBar" icon="/com/intellij/uiDesigner/icons/scrollbar.svg" removable="false" auto-create-binding="true" can-attach-label="false">
+        <default-constraints vsize-policy="6" hsize-policy="0" anchor="0" fill="2" />
+      </item>
+    </group>
+  </component>
+</project>

SLAM-Sim.iml

@@ -43,5 +43,9 @@
         <SOURCES />
       </library>
     </orderEntry>
+    <orderEntry type="library" exported="" name="ejml" level="project" />
+
+
+
   </component>
 </module>

src/Car.java

@@ -3,6 +3,9 @@ import java.util.ArrayList;
 import static java.lang.Math.PI;
 import static processing.core.PApplet.degrees;
 import static processing.core.PApplet.radians;
+
+import Graph.*;
+import Vector.Vector;
 import processing.core.PApplet;
 
 public class Car{
@@ -35,22 +38,21 @@ public class Car{
     }
 
     //draw the car and its views
-    public void drawCar(ArrayList<Wall> walls){
+    public void drawCar(PointGraph map, boolean SLAMIsHidden){
         proc.stroke(255);
         proc.ellipse(pose.x, pose.y, carWidth, carLength);
-        this.updateScan(walls);
+        this.updateScan(map);
-//        this.slam.drawLines();
+        if(!SLAMIsHidden){
+            this.slam.drawFeatures(proc);
+        }
     }
 
     //With all the views that the car has, get their point list
-    void updateScan(ArrayList<Wall> walls){
+    void updateScan(PointGraph map){
         for(View view : views){
-            view.look(walls);
+            view.calculatePointScan(map);
-        }
+            slam.RANSAC(view);
 
-        for(View view : views){
-            ArrayList<Vector> pointList = view.getPoints();
-//            slam.RANSAC(pointList, view.getFOV() / view.getRayNum());
         }
     }
 

src/Graph/Edge.java

@@ -0,0 +1,59 @@
+package Graph;
+
+public class Edge {
+    Vertex vStart = null;
+    Vertex vEnd = null;
+    float weight = 0;
+
+    /**
+     * @param vStart the vertex the edge starts at
+     * @param vEnd the vertex the edge ends at
+     * @param weight the weight of the edge
+     */
+    public Edge(Vertex vStart, Vertex vEnd, float weight){
+        this.vStart = vStart;
+        this.vEnd = vEnd;
+        this.weight = weight;
+    }
+
+    /**
+     * @param vStart the vertex the edge starts at
+     * @param vEnd the vertex the edge ends at
+     */
+    public Edge(Vertex vStart, Vertex vEnd){
+        this.vStart = vStart;
+        this.vEnd = vEnd;
+    }
+
+    Edge(){}
+
+    /**
+     * @return the weight of the edge
+     */
+    public float getWeight(){
+        return weight;
+    }
+
+    /**
+     * @param newWeight set the edge's weight to something new
+     */
+    public void setWeight(float newWeight){
+        this.weight = newWeight;
+    }
+
+    /**
+     * @return the vertex at the end of the edge
+     */
+    public Vertex getEndVertex(){
+        return vEnd;
+    }
+
+    /**
+     * @return the vertex at the start of the edge
+     */
+    public Vertex getStartVertex(){
+        return vStart;
+    }
+
+}
+

src/Graph/Graph.java

@@ -0,0 +1,225 @@
+package Graph;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.LinkedList;
+
+public class Graph {
+
+    /**
+     * Create a new empty graph
+     */
+    public Graph(){
+        // hash maps require an initial size to get started
+        adjList = new HashMap<Vertex, LinkedList<Edge>>(1024);
+    }
+
+    /**
+     * @return the total number of vertices in the graph
+     */
+    public int numVertices(){
+        return adjList.size();
+    }
+
+    /**
+     * @return the total number of edges in the graph.
+     */
+    public int numEdges(){
+        int sum = 0;
+        for(Vertex v : adjList.keySet()){
+            sum += adjList.get(v).size();
+        }
+        return sum;
+    }
+
+    /**
+     * @param v add the vertex v to the graph
+     */
+    public void addVertex(Vertex v){
+        // check if it's already in the adjacency listVertex
+        if(adjList.containsKey(v)){
+            return;
+        }
+        adjList.put(v, new LinkedList<Edge>());
+
+    }
+
+    /**
+     * @param vStart the starting vertex
+     * @param vEnd the ending vertex
+     */
+    public void addEdge(Vertex vStart, Vertex vEnd){
+        // don't add the edge if it is already added
+        for(Edge e : adjList.get(vStart)){
+            if(e.getEndVertex() == vEnd){
+                return;
+            }
+        }
+        adjList.get(vStart).add(new Edge(vStart, vEnd));
+    }
+
+    /**
+     * @brief Gets how many other vertices a given vertex points to
+     * @param v the vertex you want to know about
+     * @return the number of vertices this vertex points to
+     */
+    public int outDegree(Vertex v){
+        return adjList.get(v).size();
+    }
+
+    /**
+     * @param v the vertex of interest
+     * @return the number of edges going into the vertex
+     */
+    public int inDegree(Vertex v){
+        int count = 0;
+        for(Vertex v1 : adjList.keySet()){
+            for(Edge edge : adjList.get(v1)){
+                if(edge.getEndVertex() == v){
+                    count++;
+                }
+            }
+        }
+        return count;
+    }
+
+    /**
+     * Print out all vertexes in the graph
+     */
+    public void print(){
+        for(Vertex key : adjList.keySet()){
+            System.out.print("Key: " + key.getLabel() + ": ");
+            for(Edge edge : adjList.get(key)){
+                System.out.print(edge.getEndVertex().getLabel());
+                System.out.print(",");
+            }
+            System.out.println("NULL");
+        }
+    }
+
+    /**
+     * @param v the vertext to start the traverse at
+     * @return a list of vertexes in order of when they were visited from first to last.
+     */
+    public ArrayList<Vertex> depthFirstTraverse(Vertex v){
+        ArrayList<Vertex> vertexList = new ArrayList<Vertex>();
+        DFSTraverse(v, vertexList);
+        resetVisits();
+
+        return vertexList;
+    }
+
+    /**
+     * @param v the vertex to begin the traverse at
+     * @param vertexList the vertex list to append visited vertexes to
+     */
+    private void DFSTraverse(Vertex v, ArrayList<Vertex> vertexList){
+        vertexList.add(v);
+        v.setVisitedStatus(true);
+        LinkedList<Edge> edgeList = adjList.get(v);
+        for(Edge edge : edgeList){
+            if(!(edge.getEndVertex().visitedStatus())){
+                DFSTraverse(edge.getEndVertex(), vertexList);
+            }
+        }
+    }
+
+    /**
+     * @post all vertexes in the graph will be set to unvisited
+     */
+    private void resetVisits(){
+        for(Vertex v : adjList.keySet()){
+            v.setVisitedStatus(false);
+        }
+    }
+
+    /**
+     * @param v the vertex that you wish to see the neighbors of
+     * @return a list of vertexes that are connected to v with ingoing or outgoing edges
+     */
+    public ArrayList<Vertex> getNeightborVerts(Vertex v){
+        // iterate through all of the vertexes and make sure they're marked as unvisited
+        for(Vertex v1 : adjList.keySet()){
+            v1.setVisitedStatus(false);
+        }
+
+        ArrayList<Vertex> neighbors = new ArrayList<>();
+        for(Vertex v1 : adjList.keySet()){
+            for(Edge edge : adjList.get(v1)){
+                if(edge.getStartVertex() == v && !edge.getEndVertex().visitedStatus()){
+                    edge.getEndVertex().setVisitedStatus(true);
+                    neighbors.add(edge.getEndVertex());
+                }
+
+                if(edge.getEndVertex() == v && !edge.getStartVertex().visitedStatus()){
+                    edge.getStartVertex().setVisitedStatus(true);
+                    neighbors.add(edge.getStartVertex());
+                }
+            }
+        }
+
+        resetVisits();
+
+        return neighbors;
+    }
+
+    /**
+     * @param v the vertex that you wish to start the search at
+     * @return A list of vertexes in order of visitation where the search goes wide and then deep
+     */
+    public ArrayList<Vertex> breadthFirstSearch(Vertex v){
+        ArrayList<Vertex> queue = new ArrayList<>();
+        ArrayList<Vertex> outputList = new ArrayList<>();
+        outputList.add(v);
+        queue.add(v);
+        v.setVisitedStatus(true);
+
+        while(queue.size() > 0){
+            Vertex next = queue.get(0);
+            queue.remove(0);
+            LinkedList<Edge> edgeList = adjList.get(next);
+            for(Edge edge : edgeList){
+                if(!edge.getEndVertex().visitedStatus()){
+                    queue.add(edge.getEndVertex());
+                    outputList.add(edge.getEndVertex());
+                    edge.getEndVertex().setVisitedStatus(true);
+                }
+            }
+        }
+
+        resetVisits();
+
+        return outputList;
+    }
+
+    /**
+     * @brief remove the given vertex and all edges that reference it from the graph
+     * @param v the vertex to remove from the graph.
+     */
+    public void removeVertex(Vertex v){
+
+        // find all edges that point to the removed vertex
+        ArrayList<Edge> edgesToRemove = new ArrayList<>();
+        ArrayList<Vertex> startVertex = new ArrayList<>();
+        for(Vertex v1 : adjList.keySet()){
+            for(Edge e : adjList.get(v1)){
+                if(e.getEndVertex() == v){
+                    edgesToRemove.add(e);
+                    startVertex.add(e.getStartVertex());
+                }
+            }
+        }
+
+        // remove all of those edges from the adjList
+        int i = 0;
+        for(Edge e : edgesToRemove){
+            adjList.get(startVertex.get(i)).remove(e);
+            i++;
+        }
+        // remove the vertex from the adjacency list
+        adjList.remove(v);
+    }
+
+    protected HashMap<Vertex, LinkedList<Edge>> adjList;
+}
+

src/Graph/LineEdge.java

@@ -0,0 +1,53 @@
+package Graph;
+
+import Vector.*;
+import processing.core.PApplet;
+
+import java.awt.*;
+
+import static java.lang.Math.PI;
+
+public class LineEdge extends Edge implements LineInterface{
+    protected PointVertex vStart;
+    protected PointVertex vEnd;
+    protected Line line;
+    public LineEdge(PointVertex vStart, PointVertex vEnd) {
+        super(vStart, vEnd);
+        this.line = new Line(vStart.getPos(), vEnd.getPos());
+    }
+
+    public Vector getDirection(){
+        return line.getDirection();
+    }
+
+    public Vector getPosition(){
+        return line.getPosition();
+    }
+
+    public float getLength(){
+        return line.getLength();
+    }
+
+    public float getAngle(){
+        return line.getAngle();
+    }
+
+    public Vector endPoint(){
+        return line.endPoint();
+    }
+
+    public float getDistance(Vector point){
+        return line.getDistance(point);
+    }
+
+    public void draw(PApplet proc){
+        line.draw(proc);
+        Vector leftFlange = line.getDirection().rotate2D((float)(-3*PI/4)).normalize().mul(20);
+        Vector rightFlange = line.getDirection().rotate2D((float) (3*PI/4)).normalize().mul(20);
+        Line l1 = new Line(line.endPoint(), line.endPoint().add(leftFlange));
+        Line l2 = new Line(line.endPoint(), line.endPoint().add(rightFlange));
+        l1.draw(proc);
+        l2.draw(proc);
+    }
+
+}

src/Graph/PointGraph.java

@@ -0,0 +1,152 @@
+package Graph;
+
+import Vector.Vector;
+import processing.core.PApplet;
+
+import java.io.File;  // Import the File class
+import java.io.FileWriter;
+import java.io.IOException;  // Import the IOException class to handle errors
+
+import static java.lang.Math.pow;
+import static java.lang.Math.sqrt;
+
+import java.util.ArrayList;
+
+
+public class PointGraph extends Graph {
+    PointVertex selectedVertex;
+    public PointGraph(){
+        super();
+    }
+
+    public void draw(PApplet proc){
+        for(Vertex v : adjList.keySet()){
+            PointVertex v1 = (PointVertex) v;
+            v1.draw(proc);
+            for(Edge e : adjList.get(v)){
+                LineEdge e1 = (LineEdge) e;
+                e1.draw(proc);
+            }
+        }
+    }
+
+    public void addEdge(PointVertex vStart, PointVertex vEnd){
+        addVertex(vStart);
+
+        // don't add the edge if it is already added
+        for(Edge e : adjList.get(vStart)){
+            if(e.getEndVertex() == (Vertex) vEnd){
+                return;
+            }
+        }
+
+        addVertex(vEnd);
+        LineEdge edge = new LineEdge(vStart, vEnd);
+        adjList.get((Vertex) vStart).add(new LineEdge(vStart, vEnd));
+    }
+
+    /**
+     * @param v set this vertex as the selected vertex in the graph
+     */
+    public void setSelectedVertex(PointVertex v){
+        if(selectedVertex != null){
+            deselectVertex();
+        }
+        selectedVertex = v;
+        selectedVertex.setColor(new int[]{255, 0, 255, 0});
+    }
+
+    /**
+     * @pre a vertex needs to be selected
+     * @return the current pointvertex which is selected in the graph
+     */
+    public PointVertex getSelectedVertex(){
+        if(selectedVertex == null){
+            if(super.adjList.size() > 0){
+                selectedVertex = (PointVertex)super.adjList.keySet().iterator().next();
+            }
+            else{
+                throw new NullPointerException();
+            }
+        }
+        return selectedVertex;
+    }
+
+    /**
+     * @return true if a vertex is currently selected in the graph
+     */
+    public boolean vertexIsSelected(){
+        return selectedVertex != null;
+    }
+
+    /**
+     * @brief deselect the currently selected vertex
+     */
+    public void deselectVertex(){
+        if(selectedVertex == null){
+            return;
+        }
+        selectedVertex.setColor(new int[]{127, 255, 0, 0});
+        selectedVertex = null;
+    }
+
+    /**
+     * @param x the x coordinate to search by
+     * @param y the y coordinate to search by
+     * @return the pointvertex closest to the given x, y coordinates
+     */
+    public PointVertex getClosestVertex(Vector point){
+        if(super.adjList.size() == 0){
+            // TODO: choose a better exception name
+            throw new NullPointerException();
+        }
+
+        PointVertex closestVertex = (PointVertex) super.adjList.keySet().iterator().next();
+        float closestDist = -1;
+        for(Vertex v : super.adjList.keySet()){
+            PointVertex v1 = (PointVertex) v;
+            Vector p2 = v1.getPos();
+            float dist = p2.sub(point).mag();
+            if(dist < closestDist || closestDist == -1){
+                closestDist = dist;
+                closestVertex = v1;
+            }
+        }
+
+        return closestVertex;
+    }
+
+    public void removeVertex(PointVertex v){
+        if(selectedVertex == v){
+            selectedVertex = null;
+        }
+        super.removeVertex(v);
+    }
+
+
+    /**
+     * @return all edges in the graph
+     */
+    public ArrayList<LineEdge> getAllEdges(){
+        ArrayList<LineEdge> edges = new ArrayList<>();
+        for(Vertex v : adjList.keySet()){
+            for(Edge e : adjList.get(v)){
+                LineEdge e1 = (LineEdge) e;
+                edges.add(e1);
+            }
+        }
+        return edges;
+    }
+
+    /**
+     * @return all vertexes in the graph
+     */
+    public ArrayList<PointVertex> getAllVertexes(){
+        ArrayList<PointVertex> points = new ArrayList<>();
+        for(Vertex v : adjList.keySet()){
+            PointVertex v1 = (PointVertex) v;
+            points.add(v1);
+        }
+        return points;
+    }
+}

src/Graph/PointGraphWriter.java

@@ -0,0 +1,122 @@
+package Graph;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Scanner;
+
+public class PointGraphWriter {
+    public void save(String filename, PointGraph g) throws IOException {
+        FileWriter file = new FileWriter(filename);
+
+        file.write("numVerts," + g.numVertices());
+        file.write("\nnumEdges," + g.numEdges());
+
+        // turn the hash map into something linear
+        ArrayList<PointVertex> verts = g.getAllVertexes();
+        ArrayList<LineEdge> edges = g.getAllEdges();
+
+        // save the vertexes
+        int countVerts = 0;
+        for(PointVertex v : verts){
+            // save the vertex position
+            file.write("\nvert,"+v.getPos().x+","+v.getPos().y);
+            countVerts++;
+        }
+
+        // save the edges
+        for(Edge e : edges){
+            int idx = 0;
+            file.write("\nedge,");
+            boolean otherIsWritten = false;
+            for(PointVertex v : verts){
+                if(e.getStartVertex() == (Vertex)v){
+                    file.write("start,"+ idx);
+                    if(!otherIsWritten){
+                        file.write(",");
+                        otherIsWritten = true;
+                    }
+                }
+                else if(e.getEndVertex() == (Vertex)v){
+                    file.write("end," + idx);
+                    if(!otherIsWritten){
+                        file.write(",");
+                        otherIsWritten = true;
+                    }
+                }
+                idx++;
+            }
+        }
+        file.close();
+    }
+
+    public PointGraph loadFile(String filename) throws NumberFormatException {
+        PointGraph g = new PointGraph();
+        File file = new File(filename);
+        Scanner reader;
+        try {
+            reader = new Scanner(file);
+        }
+        catch (FileNotFoundException e){
+            System.out.println("File not found");
+            return g;
+        }
+        ArrayList<PointVertex> vertices = new ArrayList<>();
+        while(reader.hasNextLine()){
+            String line = reader.nextLine();
+            ArrayList<String> args = parseLine(line);
+            String key = args.get(0);
+            switch (key) {
+                case "numVerts" -> System.out.println("Number of Vertexes: " + Integer.parseInt(args.get(1)));
+                case "numEdges" -> System.out.println("Number of Edges: " + Integer.parseInt(args.get(1)));
+                case "vert" -> {
+                    float x = Float.parseFloat(args.get(1));
+                    float y = Float.parseFloat(args.get(2));
+                    PointVertex v = new PointVertex(x, y);
+                    g.addVertex(v);
+                    vertices.add(v);
+                }
+                case "edge" -> {
+                    int startIdx;
+                    int endIdx;
+                    if (args.get(1).contains("start")) {
+                        startIdx = Integer.parseInt(args.get(2));
+                        endIdx = Integer.parseInt(args.get(4));
+                    }
+                    else{
+                        startIdx = Integer.parseInt(args.get(4));
+                        endIdx = Integer.parseInt(args.get(2));
+                    }
+                    g.addEdge(vertices.get(startIdx), vertices.get(endIdx));
+                }
+                default -> System.out.println("Unrecognized Line: " + line);
+            }
+        }
+
+        return g;
+    }
+
+    private ArrayList<String> parseLine(String line){
+        ArrayList<String> args = new ArrayList<>();
+        StringBuilder arg = new StringBuilder();
+
+        for(char letter : line.toCharArray()){
+            if(letter == ','){
+                args.add(arg.toString());
+                arg = new StringBuilder();
+                continue;
+            }
+            if(letter == '\n'){
+                args.add(arg.toString());
+                break;
+            }
+            arg.append(letter);
+        }
+        if(!args.get(args.size()-1).contains(arg.toString())){
+            args.add(arg.toString());
+        }
+        return args;
+    }
+}

src/Graph/PointVertex.java

@@ -0,0 +1,66 @@
+package Graph;
+import Vector.Vector;
+import processing.core.PApplet;
+
+public class PointVertex extends Vertex {
+    private Vector position;
+
+    private int[] color = new int[]{127, 255, 0, 0};
+
+    /**
+     * @param xPos the x position of the vertex
+     * @param yPos the y posiiton of the vertex
+     */
+    public PointVertex(float xPos, float yPos){
+        this.position = new Vector(xPos, yPos);
+    }
+
+    public PointVertex(Vector position){
+        super();
+        this.position = position;
+    }
+
+    /**
+     * @param xPos the x position of the vertex
+     * @param yPos the y posiiton of the vertex
+     * @param label the label of the vertex
+     */
+    PointVertex(float xPos, float yPos, String label){
+        super(label);
+        this.position = new Vector(xPos, yPos);
+    }
+
+    /**
+     * @param x the new x position of the vertex
+     * @param y the new y posiiton of the vertex
+     */
+    public void setPos(float x, float y){
+        this.position = new Vector(x, y);
+    }
+
+    /**
+     * @return a two eleement float array containing the x and y coordinates of the vertex respectively.
+     */
+    public Vector getPos(){
+        return position;
+    }
+
+    /**
+     * @param newColor a 4 element int array containing th alpha, r, g ,and b components respectively
+     */
+    public void setColor(int[] newColor){
+        this.color = newColor;
+    }
+
+    /**
+     * @return a 4 element int array containing th alpha, r, g ,and b components respectively
+     */
+    public int[] getColor(){
+        return color;
+    }
+
+    public void draw(PApplet proc){
+        proc.stroke(color[1], color[2], color[3], color[0]);
+        proc.circle(position.x, position.y, 20);
+    }
+}

src/Graph/Vertex.java

@@ -0,0 +1,45 @@
+package Graph;
+
+public class Vertex {
+    private String vertexLabel;
+    private boolean isVisitedStatus = false;
+
+    /**
+     * Create a new vertex with a default label
+     */
+    public Vertex(){
+        this.vertexLabel = "Unassigned";
+    }
+
+    /**
+     * @param label create a new vertex with this label
+     */
+    public Vertex(String label){
+        this.vertexLabel = label;
+    }
+
+    /**
+     * @return the label of the vertex
+     */
+    public String getLabel(){
+        return vertexLabel;
+    }
+
+    public void setLabel(String newLabel){
+        vertexLabel = newLabel;
+    }
+
+    /**
+     * @return if the node has been visited or not
+     */
+    public boolean visitedStatus(){
+        return this.isVisitedStatus;
+    }
+
+    /**
+     * @param status set the visited status to true or false
+     */
+    public void setVisitedStatus(boolean status){
+        this.isVisitedStatus = status;
+    }
+}

src/Processing.java

@@ -1,13 +1,20 @@
+import Graph.*;
+import Vector.Vector;
 import processing.core.PApplet;
 
-import java.util.ArrayList;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+
 
 public class Processing extends PApplet {
 
     Car car;
-    ArrayList<Wall> objects = new ArrayList<>();
     public static PApplet processing;
 
+    PointGraph map = new PointGraph();
+    boolean mapIsHidden = false;
+    boolean SLAMIsHidden = false;
+
     public static void main(String[] args) {
         PApplet.main("Processing");
     }
@@ -16,21 +23,23 @@ public class Processing extends PApplet {
         processing = this;
         car = new Car(processing, 100,100,50,40);
         size(1000, 1000);
-        car.addView(180,90);
+        car.addView(90,180);
-        for(int i = 0; i < 15; i++){
+
-            Wall wall = new Wall(processing, new Vector((int)random(50, 950), (int)random(50, 950)), new Vector((int)random(50, 950), (int)random(50, 950)));
+//        for(int i = 0; i < 10; i++){
-            objects.add(wall);
+//            PointVertex vStart = new PointVertex(random(50, 950), random(50, 950));
-        }
+//            PointVertex vEnd = new PointVertex(random(50, 950), random(50, 950));
+//            map.addEdge(vStart, vEnd);
+//        }
+
     }
     public void draw(){
         background(0);
-        for(Wall object : objects){
+        if(!mapIsHidden){
-            object.drawWall();
+            map.draw(processing);
         }
-        car.drawCar(objects);
+        car.drawCar(map, SLAMIsHidden);
         strokeWeight(2);
         stroke(255);
-        //car.drive(new int[] {0, 0});
     }
 
     public void keyPressed(){
@@ -52,9 +61,64 @@ public class Processing extends PApplet {
         if(key == 'e'){
             car.setAngle(car.getAngle()-1);
         }
-
+        if(key == DELETE && map.vertexIsSelected()){
+            map.removeVertex(map.getSelectedVertex());
+        }
+        if(key == ' ' && map.vertexIsSelected()){
+            map.deselectVertex();
+        }
+        if(key == ESC){
+            System.out.println("Attempting to save map to file.");
+            try{
+                PointGraphWriter writer = new PointGraphWriter();
+                writer.save("map.txt", map);
+            }
+            catch(IOException e){
+                e.printStackTrace();
+            }
+        }
+        if(key == 'l'){
+            System.out.println("Attempting to load a map from file");
+            PointGraphWriter writer = new PointGraphWriter();
+            try {
+                map = writer.loadFile("map.txt");
+            } catch (NumberFormatException e) {
+                System.out.println("Number format incorrect");
+                e.printStackTrace();
+            }
+        }
+        if(key == 'h'){
+            mapIsHidden = !mapIsHidden;
+        }
+        if(key == 'j'){
+            SLAMIsHidden = !SLAMIsHidden;
+        }
     }
 
+    public void mousePressed(){
+        Vector clickPosition = new Vector(mouseX, mouseY);
 
-
+        if(map.numVertices() == 0){
+            PointVertex v = new PointVertex(clickPosition);
+            map.addVertex(v);
+            return;
+        }
+        PointVertex closestVertex = map.getClosestVertex(clickPosition);
+        float distance = closestVertex.getPos().sub(clickPosition).mag();
+        if(distance < 15){
+            if(map.vertexIsSelected()){
+                if(map.getSelectedVertex() == closestVertex){
+                    map.deselectVertex();
+                }
+                else{
+                    map.addEdge(map.getSelectedVertex(), closestVertex);
+                }
+                return;
+            }
+            map.setSelectedVertex(closestVertex);
+            return;
+        }
+        PointVertex v = new PointVertex(clickPosition);
+        map.addVertex(v);
+    }
 }

src/Ray.java

@@ -1,11 +1,13 @@
+import Graph.*;
+import Vector.*;
+
 import processing.core.PApplet;
-import processing.core.PVector;
 
 import java.util.ArrayList;
 
 import static processing.core.PApplet.*;
 
-public class Ray extends Line{
+public class Ray extends Line {
     float maxRayDistance = 1000;
     int[] color = new int[]{255, 255, 255};
     //takes the starting position of the ray, the length of the ray, and it's casting angle (radians)
@@ -25,17 +27,17 @@ public class Ray extends Line{
 
 
     //checks to see at what coordinate the ray will collide with an object and sets the ray length to meet that point.
-    public void castRay(ArrayList<Wall> walls){
+    public void castRay(PointGraph map){
         float shortestWallDistance = maxRayDistance;
-        int[] newColor = new int[]{255, 255, 255};
+        ArrayList<LineEdge> walls = map.getAllEdges();
-        for(Wall wall : walls){
+        for(LineEdge wall : walls){
 
             // get the necessary vectors for two parameterized lines
             // parameterized lines are of the form L = d*t + p
             Vector d1 = this.direction.normalize().mul(maxRayDistance);
-            Vector d2 = wall.direction;
+            Vector d2 = wall.getDirection();
             Vector p1 = this.position;
-            Vector p2 = wall.position;
+            Vector p2 = wall.getPosition();
 
             // calculate the parameters for the intersection t and u
             float t = -(d2.x*(p2.y-p1.y) + d2.y*(p1.x-p2.x))/(d1.x*d2.y - d2.x*d1.y);
@@ -50,7 +52,6 @@ public class Ray extends Line{
             float distance = d1.mul(t).add(p1).sub(this.position).mag();
             if(distance < shortestWallDistance){
                 shortestWallDistance = distance;
-                newColor = new int[]{wall.r, wall.g, wall.b};
             }
 
         }
@@ -58,11 +59,9 @@ public class Ray extends Line{
         // if we collided with a wall, set the ray's length to the distance from it to the collision
         if(shortestWallDistance != maxRayDistance){
             this.direction = this.direction.normalize().mul(shortestWallDistance);
-            this.color = newColor;
         }
         else{
             this.direction = this.direction.normalize().mul(maxRayDistance);
-            this.color = new int[]{255, 255, 255};
         }
     }
 
@@ -72,13 +71,13 @@ public class Ray extends Line{
 
 
     public boolean hasCollided(){
-        return this.direction.mag() != maxRayDistance;
+        return abs(this.direction.mag() - maxRayDistance) > 0.001;
     }
 
     //returns the absolute position of the point
     public Vector getPoint(){
         if(this.direction.mag() == 0){
-            return new Vector();
+            return this.position;
         }
 
         return this.position.add(this.direction);
@@ -91,8 +90,8 @@ public class Ray extends Line{
     public void setRayLength(int rayLength){this.direction = this.direction.normalize().mul(rayLength);}
 
     public void setAngle(float angle){
-        float distance = this.direction.mag();
+        float currentAngle = direction.angle();
-        this.direction = new Vector(cos(angle), sin(angle)).mul(distance);
+        this.direction = direction.rotate2D(angle - currentAngle);
     }
 
 }

src/SLAM.java

@@ -1,13 +1,16 @@
+import Vector.*;
 import processing.core.*;
 
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 
+import static java.lang.Math.random;
 import static processing.core.PApplet.*;
 
 public class SLAM{
     ArrayList<Line> lines = new ArrayList<>();
+    ShortTermMem unassociatedPoints = new ShortTermMem();
     private static PApplet proc;
 
     SLAM(PApplet processing){
@@ -16,38 +19,41 @@ public class SLAM{
 
     /**
      * @param set the set to take a sub sample of
-     * @param indexRange the range within to take the sub sample
      * @param subSampleSize the size of the sub sample
-     * @return A random subset of the set within an indexRange and of size: subSampleSize
+     * @param minAngle the minimum angle allowed in the subset
+     * @param maxAngle the maximum angle allowed in the subset
+     * @return A random subset of the set within the angle range
      */
-    private List<Vector> randomSample(ArrayList<Vector> set, int indexRange, int subSampleSize){
+    private List<Vector> randomSampleInAngleRange(ArrayList<Vector> set, int subSampleSize, float minAngle, float maxAngle){
-        // select a random laser data reading
-        int randomIdx = (int) proc.random(set.size() - 1); // index of starter reading
-        Vector point = set.get(randomIdx); // point of starter reading
 
-        // get a random sample of size numSampleReadings within degreeRange degrees of this laser reading.
+        // create an arraylist with all points within the angle range from the given set
-        List<Vector> subSample;
+        ArrayList<Vector> pointsInAngleRange = new ArrayList<>();
-        int rangeStart = randomIdx - indexRange >= 0 ? randomIdx - indexRange : 0;
+        for(Vector point : set){
-        int rangeEnd = randomIdx + indexRange < set.size() ? randomIdx + indexRange : set.size()-1;
+            if(minAngle <= point.z && point.z <= maxAngle){
-        subSample = set.subList(rangeStart, rangeEnd); // get the sub-sample
+                pointsInAngleRange.add(point);
-        Collections.shuffle(subSample); // shuffle the list
+            }
-        List<Vector> randomSample = subSample.subList(0, rangeEnd-rangeStart); // get our random sample
-        if (!randomSample.contains(point)) {
-            randomSample.add(point);
         }
 
-        return randomSample;
+        // shuffle the list to randomize it
+        Collections.shuffle(pointsInAngleRange);
+
+        // if the list is too small, just return the whole list
+        if(pointsInAngleRange.size() < subSampleSize){
+            return pointsInAngleRange;
+        }
+        // return a subSample of the list
+        return pointsInAngleRange.subList(0, subSampleSize);
     }
 
     /**
-     * @param originalList the list which the randomSample of points originated from
      * @param randomSample a random subsampling of points from the originalList
      * @param maxRange the maximum distance away from the line of best fit of the subSample of points for a given point's consensus to count.
      * @param consensus the number of points that have to give their consensus for the line of best fit to count as a valid feature.
      */
-    private void extractFeature(ArrayList<Vector> originalList, List<Vector> randomSample, float maxRange, int consensus){
+    private void extractFeature(List<Vector> randomSample, float maxRange, int consensus){
         // get a line of best fit for this list.
         Line bestFit = new Line(randomSample);
+        // check that there are enough points in the sample that are less than the maxRange away to form a consensus
         int count = 0;
         ArrayList<Vector> newRandomSample = new ArrayList<>();
         for (Vector v : randomSample) {
@@ -62,44 +68,66 @@ public class SLAM{
             lines.add(bestFit);
             // remove the associated readings from the total available readings.
             for (Vector v : newRandomSample) {
-                originalList.remove(v);
+                this.unassociatedPoints.remove(v);
             }
         }
     }
 
-    /**
+    private void fitToPreviousReadings(List<Vector> sample, float maxRange){
-     * @param newPoints a new scan of points to perform feature detection on
+        // keep track of points that were succesffully associated so they can be removed from the sample at the end
-     * @param raysPerDegree How many degrees apart are each ray that was cast
+        ArrayList<Vector> pointsToRemove = new ArrayList<>();
-     */
+        // try to associate points from the smaple with pre-existing lines
-    public void RANSAC(ArrayList<Vector> newPoints, float raysPerDegree){
+        for(Vector v: sample){
-        float degreeRange = radians(10/2); // range to randomly sample readings within
+            for(Line l : lines){
-        int indexRange = (int) (degreeRange / raysPerDegree);
+                if(l.getDistance(v) < maxRange){
-        int numSampleReadings = 10; // number of readings to randomly sample
+                    l.refitLine(v);
-        // constrain numSampleReadings so that it cant be higher than possible
+                    pointsToRemove.add(v);
-        if(numSampleReadings >= 2 * indexRange){
+                }
-            numSampleReadings = 2 * indexRange;
+            }
         }
-        int consensus = 6; // the number of points that need to lie near a line for it to be considered valid.
+
+        for(Vector v : pointsToRemove){
+            sample.remove(v);
+        }
+    }
+
+    /**
+     * @param view a laser scan view
+     */
+    public void RANSAC(View view){
+        unassociatedPoints.addScan(view.getPos(), view.getScan().getPoints());
+
+        float degreeRange = radians(5); // range to randomly sample readings within
+        int numSampleReadings = 15; // number of readings to randomly sample
+
+        int consensus = 10; // the number of points that need to lie near a line for it to be considered valid.
         float maxRange = 10; // the maximum distance a point can be away from the line for it to count as a consensus
 
         // this for loop determines the maximum number of trials we're willing to do.
         for(int j = 0; j < 20; j++) {
             // if there aren't enough points left in the set to form a consensus, we're done.
-            if(newPoints.size() < consensus){
+            if(this.unassociatedPoints.size() < maxRange){
                 break;
             }
 
-            // get a random sub sample of newPoints within the index range of a given size
+            // get a random angle between -PI and PI
-            List<Vector> randomSample = this.randomSample(newPoints, indexRange, numSampleReadings);
+            float randomAngle = (float) (2*PI*(random()) - 0.5);
 
-            // check if the sub sample forms a valid line and remove the randomSample points if it does.
+            // get a random sub sample of newPoints within the index range of a given size
-            extractFeature(newPoints, randomSample, maxRange, consensus);
+            List<Vector> randomSample = this.randomSampleInAngleRange(this.unassociatedPoints.getPoints(), numSampleReadings, randomAngle-degreeRange, randomAngle+degreeRange);
+
+            if(randomSample.size() >= numSampleReadings){
+                // try to associate points from the sample with previously made lines
+                fitToPreviousReadings(randomSample, maxRange);
+                // check if the sub sample forms a valid line and remove the randomSample points if it does.
+                extractFeature(randomSample, maxRange, consensus);
+            }
 
         }
 
     }
 
-    public void drawLines(){
+    public void drawFeatures(PApplet proc){
         for(Line line : lines){
             line.draw(proc);
         }

src/ScanGraph/ScanEdge.java

@@ -0,0 +1,47 @@
+package ScanGraph;
+
+import Graph.Edge;
+import Vector.Line;
+import Vector.LineInterface;
+import Vector.Vector;
+import processing.core.PApplet;
+
+import static java.lang.Math.PI;
+
+public class ScanEdge extends Edge {
+    protected Line line;
+
+    // Additional properties specific to scan edges
+    private boolean isLoopClosure = false;
+
+    /**
+     * @brief Constructor for a scan edge
+     * @param vStart the starting vertex
+     * @param vEnd   the ending vertex
+     */
+    public ScanEdge(ScanPoint vStart, ScanPoint vEnd){
+        super(vStart, vEnd);
+
+        this.line = new Line(vStart.getPos(), vEnd.getPos());
+    }
+
+    /**
+     * @brief Constructor for a scan edge
+     * @param vStart the starting vertex
+     * @param vEnd   the ending vertex
+     * @param weight the weight of the edge
+     */
+    public ScanEdge(ScanPoint vStart, ScanPoint vEnd, float weight) {
+        super(vStart, vEnd, weight);
+        this.line = new Line(vStart.getPos(), vEnd.getPos());
+    }
+
+    // Getter and setter for loop closure flag
+    public boolean isLoopClosure() {
+        return isLoopClosure;
+    }
+
+    public void setLoopClosure(boolean loopClosure) {
+        isLoopClosure = loopClosure;
+    }
+}

src/ScanGraph/ScanGraph.java

@@ -0,0 +1,170 @@
+package ScanGraph;
+
+import Graph.Graph;
+import Graph.Edge;
+import Graph.Vertex;
+import Vector.Vector;
+import org.ejml.simple.SimpleMatrix;
+import org.ejml.simple.SimpleSVD;
+
+import java.util.ArrayList;
+public class ScanGraph extends Graph {
+
+    ScanPoint lastPoint;
+
+    public ScanGraph(ScanPoint startingPoint) {
+        super();
+        this.lastPoint = startingPoint;
+    }
+
+    /**
+     * @brief Add a new scan to the graph
+     * @param newScan the new scan to add
+     */
+    public void addScan(ScanPoint newScan) {
+        addVertex(newScan);
+
+        // check if the new scan matches any of the existing scans
+        MatchedScanTransform matchedScan = getAssociatedScan(newScan);
+        if (matchedScan.scan != null) {
+            // if it does, add a loop closure constraint
+            addLoopClosureConstraint(this.lastPoint, matchedScan);
+        }
+        else{
+            // if it doesn't match anything else, add an edge between the last scan and the new scan
+            ScanEdge edge = new ScanEdge(this.lastPoint, newScan);
+            adjList.get((Vertex) this.lastPoint).add(edge);
+        }
+
+        this.lastPoint = newScan;
+    }
+
+    /**
+     * @param newScan the scan to match
+     * @return null if no match can be found, or an existing scan the matches the new scan.
+     * @brief Get a new scan in and try to match it with all other scans in the graph
+     */
+    private MatchedScanTransform getAssociatedScan(ScanPoint newScan) {
+        ScanMatcher matcher = new ScanMatcher();
+        ScanPoint matchedScan = null;
+        // go through all of our available scans and try to match the new scan with the old scans. If no match can be found return null
+        for (Vertex v : adjList.keySet()) {
+            ScanPoint referenceScan = (ScanPoint) v;
+            matchedScan = matcher.iterativeScanMatch(referenceScan, newScan, 0.00001F, 5);
+
+            if(matchedScan != null){
+                // apply the transformation to the new scan
+                break;
+            }
+        }
+
+        return new MatchedScanTransform(matcher.getRotationMatrix(), matcher.getTranslationVector(), matchedScan);
+    }
+
+    /**
+     * @param referenceScan the existing scan in the graph
+     * @param matchedScan the new scan that matches the reference scan
+     */
+    private void addLoopClosureConstraint(ScanPoint referenceScan, MatchedScanTransform matchedScan) {
+        // Compute relative transformation between referenceScan and newScan
+        // You need to implement the logic for computing the relative transformation
+
+        // Create a loop closure edge and add it to the graph
+        ScanEdge loopClosureEdge = new ScanEdge(referenceScan, matchedScan.scan);
+        loopClosureEdge.setLoopClosure(true);  // Mark the edge as a loop closure
+        adjList.get(referenceScan).add(loopClosureEdge);
+
+        // Optimize the graph after adding the loop closure constraint
+        optimizeGraph();
+    }
+
+    /**
+     * Perform graph optimization using the Levenberg-Marquardt algorithm
+     */
+    private void optimizeGraph() {
+        // Create a matrix for pose parameters (you may need to adjust the size based on your requirements)
+        int numPoses = adjList.size();
+        int poseDim = 3; // Assuming 3D poses
+        SimpleMatrix poses = new SimpleMatrix(numPoses * poseDim, 1);
+
+        // Populate the poses matrix with current pose estimates from the graph
+        int i = 0;
+        for (Vertex v : adjList.keySet()) {
+            ScanPoint scan = (ScanPoint) v;
+            Vector poseVector = scan.getPos(); // You need to implement the method to get the pose vector
+            poses.set(i++, 0, poseVector.x);
+            poses.set(i++, 0, poseVector.y);
+            poses.set(i++, 0, scan.getAngle());
+        }
+
+        // TODO: Create a matrix for loop closure constraints (you need to implement this)
+        SimpleMatrix loopClosureConstraints = computeLoopClosureConstraints();
+
+        // Use Levenberg-Marquardt optimization to adjust poses
+        SimpleSVD<SimpleMatrix> svd = poses.svd();
+        SimpleMatrix U = svd.getU();
+        SimpleMatrix S = svd.getW();
+        SimpleMatrix Vt = svd.getV().transpose();
+
+        // Adjust poses using loop closure constraints
+        SimpleMatrix adjustment = Vt.mult(loopClosureConstraints).mult(U.transpose())
+                .scale(0.01); // Adjust this factor based on your problem
+
+        // Update the poses in the graph and handle loop closure edges
+        i = 0;
+        for (Vertex v : adjList.keySet()) {
+            ScanPoint scan = (ScanPoint) v;
+            scan.setPos(new Vector(adjustment.get(i++, 0), adjustment.get(i++, 0), adjustment.get(i++, 0)));
+
+            // TODO: Handle loop closure edges
+            for (Edge edge : adjList.get(v)) {
+                ScanEdge scanEdge = (ScanEdge) edge;
+                if (scanEdge.isLoopClosure()) {
+                    // Update any additional information specific to loop closure edges
+                    // For example, you might update the weight or perform other adjustments
+                    // based on the loop closure information
+                }
+            }
+        }
+    }
+
+    /**
+     * @return Matrix representing loop closure constraints (you need to implement this)
+     */
+    private SimpleMatrix computeLoopClosureConstraints() {
+        // Implement the logic to compute loop closure constraints
+        // This matrix should represent the relative transformation between loop closure nodes
+        // It may involve iterating through loop closure edges and extracting relevant information
+        // You may use a similar structure to the poses matrix
+        // For simplicity, this example assumes a 3D pose with translation only
+        int numPoses = adjList.size();
+        int poseDim = 3;
+        SimpleMatrix loopClosureConstraints = new SimpleMatrix(numPoses * poseDim, 1);
+
+        // Populate loopClosureConstraints matrix with relevant information
+
+        return loopClosureConstraints;
+    }
+}
+
+/**
+ * @brief struct to hold the rotation and translation between two scans
+ */
+class MatchedScanTransform{
+    public SimpleMatrix rotation;
+    public SimpleMatrix translation;
+
+    public ScanPoint scan;
+
+    /**
+     * @brief constructor
+     * @param rotation the rotation between the two scans
+     * @param translation the translation between the two scans
+     * @param scan the scan that was matched
+     */
+    MatchedScanTransform(SimpleMatrix rotation, SimpleMatrix translation, ScanPoint scan){
+        this.rotation = rotation;
+        this.translation = translation;
+        this.scan = scan;
+    }
+}

src/ScanGraph/ScanMatcher.java

@@ -0,0 +1,302 @@
+package ScanGraph;
+
+import Vector.Vector;
+import org.ejml.simple.SimpleMatrix;
+import org.ejml.simple.SimpleSVD;
+
+import java.util.ArrayList;
+
+import static java.lang.Math.abs;
+
+/**
+ * @brief A class that can match two point scans together
+ */
+public class ScanMatcher{
+    // A 2x2 matrix describing a rotation to apply to the new scan
+    public SimpleMatrix rotationMatrix = null;
+
+    // A 2x1 matrix describing a translation to apply to the new scan
+    public SimpleMatrix translationVector = null;
+
+    public ScanMatcher(){
+    }
+
+    /**
+     * @brief iteratively calculate new rotation and transpose matrices to determien if the two scans match
+     * @param referenceScan the scan to be referenced
+     * @param newScan the scan that will be rotated and moved until it matches the reference scan
+     * @param iterations The number of iterations that the scan matcher will attempt
+     * @param errorThreshold The error threshold that the match will have to meet before considering it a valid match
+     */
+    public ScanPoint iterativeScanMatch(ScanPoint referenceScan, ScanPoint newScan, float errorThreshold, int iterations){
+        // make a copy of the new scan so we don't modify the original
+        ScanPoint scanBeingMatched = new ScanPoint(newScan);
+
+        // calculate the rotation and translation matrices between the two scans
+        this.calculateRotationAndTranslationMatrices(referenceScan, scanBeingMatched);
+
+        SimpleMatrix cumulativeRotationMatrix = new SimpleMatrix(this.rotationMatrix);
+        SimpleMatrix cumulativeTranslationVector = new SimpleMatrix(this.translationVector);
+
+        // iterate through the scan matching algorithm
+        for (int i = 0; i < iterations; i++) {
+            // calculate the rotation and translation matrices between the two scans
+            this.calculateRotationAndTranslationMatrices(referenceScan, scanBeingMatched);
+            // apply the rotation and translation matrices to the new scan
+            scanBeingMatched = this.applyRotationAndTranslationMatrices(scanBeingMatched);
+            // calculate the error between the new scan and the reference scan
+            float error = this.getError(referenceScan, scanBeingMatched);
+            // if the error is less than the error threshold, then we have a valid match
+            if(error < errorThreshold){
+                this.rotationMatrix = cumulativeRotationMatrix;
+                this.translationVector = cumulativeTranslationVector;
+                return scanBeingMatched;
+            }
+            // otherwise, we need to keep iterating
+            // add the rotation and translation matrices to the cumulative rotation and translation matrices
+            cumulativeRotationMatrix = cumulativeRotationMatrix.mult(this.rotationMatrix);
+            cumulativeTranslationVector = cumulativeTranslationVector.plus(this.translationVector);
+        }
+
+        // if we get to this point, then we have not found a valid match
+        return null;
+    }
+
+    /**
+     * @brief Compute the cross covariance matrix between the new scan and the reference scan
+     * @return a 2x2 matrix containing the cross covariance matrix
+     */
+    private SimpleMatrix crossCovarianceMatrix(ScanPoint referenceScan, ScanPoint newScan, CorrespondenceMatrix correspondenceMatrix){
+
+        Vector referenceScanAveragePosition = correspondenceMatrix.getAverageOldPosition();
+        Vector newScanAveragePosition = correspondenceMatrix.getAverageNewPosition();
+
+        // compute the cross covariance matrix which is given by the formula:
+        // covariance = the sum from 1 to N of (p_i) * (q_i)^T
+        // where p_i is the ith point in the new scan and q_i is the ith point in the reference scan and N is the number of points in the scan
+        // the cross covariance matrix is a 2x2 matrix
+        float[][] crossCovarianceMatrix = new float[2][2];
+
+        for (int i = 0; i < correspondenceMatrix.getOldPointIndices().size(); i++) {
+            int oldIndex = correspondenceMatrix.getOldPointIndices().get(i);
+            int newIndex = correspondenceMatrix.getNewPointIndices().get(i);
+            Vector oldPoint = referenceScan.getPoints().get(oldIndex);
+            Vector newPoint = newScan.getPoints().get(newIndex);
+            if (oldPoint != null && newPoint != null) {
+                Vector oldPointOffset = oldPoint.sub(referenceScanAveragePosition);
+                Vector newPointOffset = newPoint.sub(newScanAveragePosition);
+                crossCovarianceMatrix[0][0] += oldPointOffset.x * newPointOffset.x;
+                crossCovarianceMatrix[0][1] += oldPointOffset.x * newPointOffset.y;
+                crossCovarianceMatrix[1][0] += oldPointOffset.y * newPointOffset.x;
+                crossCovarianceMatrix[1][1] += oldPointOffset.y * newPointOffset.y;
+            }
+        }
+        return new SimpleMatrix(crossCovarianceMatrix);
+    }
+
+    /**
+     * @brief Compute the rotation and translation matrices between the new scan and the reference scan. Then cache them as private variables.
+     * The rotation matrix is a 2x2 matrix and the translation vector is a 2x1 matrix
+     */
+    public void calculateRotationAndTranslationMatrices(ScanPoint referenceScan, ScanPoint newScan){
+        CorrespondenceMatrix correspondenceMatrix = new CorrespondenceMatrix(newScan, referenceScan);
+
+        // compute the rotation matrix which is given by the formula:
+        // R = V * U^T
+        // where V and U are the singular value decomposition of the cross covariance matrix
+        // the rotation matrix is a 2x2 matrix
+        SimpleMatrix crossCovarianceMatrixSimple = crossCovarianceMatrix(referenceScan, newScan, correspondenceMatrix);
+        SimpleSVD<SimpleMatrix> svd = crossCovarianceMatrixSimple.svd();
+        this.rotationMatrix = svd.getU().mult(svd.getV().transpose());
+        // calculate what the angle of the rotation matrix is
+        float angle = (float) Math.atan2(this.rotationMatrix.get(1, 0), this.rotationMatrix.get(0, 0));
+        // scale the angle by a small amount to make the rotation matrix more accurate
+        angle*= 1.75F;
+        this.rotationMatrix = new SimpleMatrix(new double[][]{{Math.cos(angle), -Math.sin(angle)}, {Math.sin(angle), Math.cos(angle)}});
+
+        // percentage of the local position to use in the translation calculation
+        double weightedAverage = 0.9;
+
+        SimpleMatrix localNewScanAveragePosition = new SimpleMatrix(correspondenceMatrix.getAverageNewPosition().toArray());//this.averageScanPosition(newScan);
+        SimpleMatrix globalNewScanAveragePosition = new SimpleMatrix(this.averageScanPosition(newScan));
+        SimpleMatrix weightedAverageNewScanPostion = localNewScanAveragePosition.scale(weightedAverage).plus(globalNewScanAveragePosition.scale(1-weightedAverage));
+
+        SimpleMatrix localReferenceScanAveragePosition = new SimpleMatrix(correspondenceMatrix.getAverageOldPosition().toArray()); //this.averageScanPosition(referenceScan);
+        SimpleMatrix globalReferenceScanAveragePosition = new SimpleMatrix(this.averageScanPosition(referenceScan));
+        SimpleMatrix weightedAverageReferenceScanPostion = localReferenceScanAveragePosition.scale(weightedAverage).plus(globalReferenceScanAveragePosition.scale(1-weightedAverage));
+
+
+        this.translationVector = weightedAverageReferenceScanPostion.minus(rotationMatrix.mult(weightedAverageNewScanPostion));
+    }
+
+    public SimpleMatrix getRotationMatrix(){
+        return this.rotationMatrix;
+    }
+
+    public SimpleMatrix getTranslationVector(){
+        return this.translationVector;
+    }
+
+    public ScanPoint applyRotationAndTranslationMatrices(ScanPoint newScan){
+        // copy the new scan so we don't modify the original
+        ScanPoint tempScan = new ScanPoint(newScan);
+        // apply the rotation matrix and translation vector to the new scan
+        for (int i = 0; i < tempScan.getPoints().size(); i++) {
+            Vector point = tempScan.getPoints().get(i);
+            if (point != null) {
+                SimpleMatrix pointMatrix = new SimpleMatrix(point.toArray());
+                SimpleMatrix newPointMatrix = rotationMatrix.mult(pointMatrix).plus(translationVector);
+                tempScan.getPoints().set(i, new Vector((float) newPointMatrix.get(0), (float) newPointMatrix.get(1)));
+            }
+        }
+        newScan.UpdatePose(rotationMatrix, translationVector);
+        return tempScan;
+    }
+
+    /**
+     * @brief Compute the average position of the scan
+     * @param scan the scan to compute the average position of
+     * @return a 2x1 matrix containing the x,y coordinates of the average position of the scan
+     */
+    private SimpleMatrix averageScanPosition(ScanPoint scan){
+        Vector averagePosition = new Vector(0, 0);
+        int invalidPoints = 0;
+        for (Vector point : scan.getPoints()) {
+            if (point != null) {
+                averagePosition = averagePosition.add(point);
+            }
+            else{
+                invalidPoints++;
+            }
+        }
+        return new SimpleMatrix(averagePosition.div(scan.getPoints().size() - invalidPoints).toArray());
+    }
+
+    public float getError(ScanPoint referenceScan, ScanPoint newScan){
+        // calculate the error between the new scan and the reference scan
+        // q is reference scan and p is new scan
+        // error is given as abs(Q_mean - R * P_mean)
+        // where Q_mean is the average position of the reference scan
+        // P_mean is the average position of the new scan
+        // R is the rotation matrix
+
+        SimpleMatrix newScanAveragePosition = averageScanPosition(newScan);
+        SimpleMatrix referenceScanAveragePosition = averageScanPosition(referenceScan);
+        SimpleMatrix error = referenceScanAveragePosition.minus(rotationMatrix.mult(newScanAveragePosition));
+        return (float) abs(error.elementSum());
+    }
+}
+
+/**
+ * @brief A class to hold the correspondence matrix between two scans
+ * The correspondence matrix is a 3xN matrix where N is the number of valid points in the scan.
+ * This calculates the closest point in the old scan for each point in the new scan and gets rid of redundant closest points.
+ */
+class CorrespondenceMatrix{
+    private ArrayList<Integer> oldPointIndices = new ArrayList<>();
+    private ArrayList<Integer> newPointIndices = new ArrayList<>();
+    private ArrayList<Float> distances = new ArrayList<>();
+
+    private Vector averageOldPosition = new Vector(0, 0);
+    private Vector averageNewPosition = new Vector(0, 0);
+
+    CorrespondenceMatrix(ScanPoint newScan, ScanPoint oldScan){
+        this.calculateCorrespondenceMatrix(newScan, oldScan);
+        this.calculateAveragePositions(newScan, oldScan);
+    }
+
+    public ArrayList<Integer> getOldPointIndices(){
+        return this.oldPointIndices;
+    }
+
+    public ArrayList<Integer> getNewPointIndices(){
+        return this.newPointIndices;
+    }
+
+    public ArrayList<Float> getDistances(){
+        return this.distances;
+    }
+
+    public Vector getAverageOldPosition(){
+        return this.averageOldPosition;
+    }
+
+    public Vector getAverageNewPosition(){
+        return this.averageNewPosition;
+    }
+
+    private void calculateAveragePositions(ScanPoint newScan, ScanPoint oldScan){
+        int invalidPoints = 0;
+        for (int i = 0; i < this.oldPointIndices.size(); i++){
+            int oldIndex = this.oldPointIndices.get(i);
+            int newIndex = this.newPointIndices.get(i);
+            Vector oldPoint = oldScan.getPoints().get(oldIndex);
+            Vector newPoint = newScan.getPoints().get(newIndex);
+            if (oldPoint != null && newPoint != null) {
+                this.averageOldPosition = this.averageOldPosition.add(oldPoint);
+                this.averageNewPosition = this.averageNewPosition.add(newPoint);
+            }
+            else{
+                invalidPoints++;
+            }
+        }
+        this.averageOldPosition = this.averageOldPosition.div(this.oldPointIndices.size() - invalidPoints);
+        this.averageNewPosition = this.averageNewPosition.div(this.newPointIndices.size() - invalidPoints);
+    }
+
+    /**
+     * @brief Calculate the correspondence matrix between two scans
+     * @param newScan the new scan
+     * @param referenceScan the reference scan
+     */
+    private void calculateCorrespondenceMatrix(ScanPoint newScan, ScanPoint referenceScan) {
+        for (int newPointIndex = 0; newPointIndex < newScan.getPoints().size(); newPointIndex++) {
+            Vector newPoint = newScan.getPoints().get(newPointIndex);
+
+            // Skip null points in the new scan
+            if (newPoint == null) {
+                continue;
+            }
+
+            float closestDistance = Float.MAX_VALUE;
+            int closestIndex = -1;
+
+            for (int oldPointIndex = 0; oldPointIndex < referenceScan.getPoints().size(); oldPointIndex++) {
+                Vector oldPoint = referenceScan.getPoints().get(oldPointIndex);
+
+                // Skip null points in the old scan
+                if (oldPoint == null) {
+                    continue;
+                }
+
+                float distance = newPoint.sub(oldPoint).mag();
+
+                if (distance < closestDistance) {
+                    closestDistance = distance;
+                    closestIndex = oldPointIndex;
+                }
+            }
+
+            // if we find a closest point...
+            if (closestIndex != -1) {
+                // check if the oldPointIndex is already in the list of oldPointIndices
+                if(this.oldPointIndices.contains(closestIndex)){
+                    int index = this.oldPointIndices.indexOf(closestIndex);
+                    // if the index is already in our list, then we need to check if the new point is closer than the old point
+                    if(this.distances.get(index) > closestDistance){
+                        // if the new point is closer than the old point, then we need to replace the old point with the new point
+                        this.oldPointIndices.set(index, closestIndex);
+                        this.newPointIndices.set(index, newPointIndex);
+                        this.distances.set(index, closestDistance);
+                    }
+                }
+                // if the index is not in our list, then we need to add it
+                else{
+                    this.oldPointIndices.add(closestIndex);
+                    this.newPointIndices.add(newPointIndex);
+                    this.distances.add(closestDistance);
+                }
+            }
+        }
+    }
+}

src/ScanGraph/ScanPoint.java

@@ -0,0 +1,68 @@
+package ScanGraph;
+
+import Graph.Vertex;
+import Vector.Vector;
+import org.ejml.simple.SimpleMatrix;
+
+import java.util.ArrayList;
+
+public class ScanPoint extends Vertex{
+
+    private Vector position;
+    private float orientation;
+    private ArrayList<Vector> scan;
+
+    public ScanPoint(Vector scanPosition, float orientation, ArrayList<Vector> scan) {
+        super();
+        this.position = scanPosition;
+        this.orientation = orientation;
+        this.scan = scan;
+    }
+
+    /**
+     * @brief Copy constructor
+     * @param other The scan point to copy
+     */
+    public ScanPoint(ScanPoint other){
+        super();
+        this.position = new Vector(other.getPos().x, other.getPos().y);
+        this.orientation = other.getAngle();
+        this.scan = new ArrayList<>(other.getPoints());
+    }
+
+    /**
+     * @return a two eleement float array containing the x and y coordinates of the vertex respectively.
+     */
+    public Vector getPos(){
+        return position;
+    }
+
+    public void setPos(Vector pos){
+        this.position = pos;
+    }
+
+    public float getAngle(){
+        return this.orientation;
+    }
+
+    public ArrayList<Vector> getPoints(){
+        return this.scan;
+    }
+
+    /**
+     * @brief Update the pose of the scan point
+     * @param rotation The rotation matrix to apply to the scan point
+     * @param translation The translation matrix to apply to the scan point
+     */
+    public void UpdatePose(SimpleMatrix rotation, SimpleMatrix translation){
+        SimpleMatrix pose = new SimpleMatrix(3,1);
+        pose.set(0,0, this.position.x);
+        pose.set(1,0, this.position.y);
+        pose.set(2,0, this.orientation);
+        SimpleMatrix newPose = translation.plus(rotation.mult(pose));
+        this.position.x = (float)newPose.get(0,0);
+        this.position.y = (float)newPose.get(1,0);
+        this.orientation = (float)newPose.get(2,0);
+    }
+
+}

src/ShortTermMem.java

@@ -0,0 +1,59 @@
+import java.util.ArrayList;
+import Vector.Vector;
+public class ShortTermMem {
+    ArrayList<ArrayList<Vector>> scans = new ArrayList<>();
+    ArrayList<Vector> scanPositions = new ArrayList<>();
+
+    ArrayList<Long> scanTimes = new ArrayList<>();
+    private int size = 0;
+
+    public void addScan(Vector scanPosition, ArrayList<Vector> scan){
+        size += scan.size();
+        scans.add(scan);
+        scanPositions.add(scanPosition);
+        scanTimes.add(System.currentTimeMillis());
+        purgeScans();
+    }
+
+    public ArrayList<Vector> getPoints(){
+        ArrayList<Vector> points = new ArrayList<>();
+        for(ArrayList<Vector> pointList : this.scans){
+            points.addAll(pointList);
+        }
+        return points;
+    }
+
+    public void remove(Vector point){
+        for(ArrayList<Vector> pointList : this.scans){
+            int listSize = pointList.size();
+            pointList.remove(point);
+            if(listSize - pointList.size() != 0){
+                size--;
+                break;
+            }
+        }
+    }
+
+    private void purgeScans(){
+        long currentTime = System.currentTimeMillis();
+        int i = scanTimes.size();
+
+        // loop through the list backwards and remove all scans that are over second old
+        // we loop backwards to avoid removal conflicts
+        while(i > 0){
+            i--;
+            long dt = currentTime - scanTimes.get(i);
+            if(dt < 1000){
+                continue;
+            }
+            size -= scans.get(i).size();
+            scanTimes.remove(i);
+            scanPositions.remove(i);
+            scans.remove(i);
+        }
+    }
+
+    public int size(){
+        return this.size;
+    }
+}

src/Vector.java

@@ -1,83 +0,0 @@
-import static java.lang.Math.*;
-
-public class Vector {
-    public float x = 0;
-    public float y = 0;
-    public float z = 0;
-
-    Vector(){}
-    Vector(float x, float y){
-        this.x = x;
-        this.y = y;
-    }
-    
-    Vector(float x, float y, float z){
-        this.x = x;
-        this.y = y;
-        this.z = z;
-    }
-    
-    Vector add(Vector other){
-        return new Vector(this.x + other.x, this.y + other.y, this.z + other.z);
-    }
-
-    Vector add(float x, float y){
-        return new Vector(this.x + x, this.y + y);
-    }
-
-    Vector add(float x, float y, float z){
-        return new Vector(this.x + x, this.y + y, this.z + z);
-    }
-    
-    Vector sub(Vector other){
-        return new Vector(this.x - other.x, this.y - other.y, this.z - other.z);
-    }
-
-    Vector sub(float x, float y){
-        return new Vector(this.x - x, this.y - y);
-    }
-
-    Vector sub(float x, float y, float z){
-        return new Vector(this.x - x, this.y - y, this.z - z);
-    }
-    
-    Vector mul(float scalar){
-        return new Vector(this.x * scalar, this.y * scalar, this.z * scalar);
-    }
-    
-    Vector div(float scalar){
-        return mul(1/scalar);
-    }
-    
-    float mag(){
-        return (float)sqrt(x*x + y*y + z*z);
-    }
-
-    float dot(Vector other){
-        return x * other.x + y * other.y + z * other.z;
-    }
-
-    Vector cross(Vector other){
-        return new Vector(this.y*other.z - this.z*other.y, this.z*other.x - this.x*other.z, this.x*other.y - this.y*other.x);
-    }
-
-    Vector normalize(){
-        float mag = this.mag();
-        return new Vector(x / mag, y / mag, z / mag);
-    }
-
-    /**
-     * @param other
-     * @return
-     */
-    float angleDiff(Vector other){
-        float dot = this.dot(other);     // dot product
-        float det = this.x*other.y - this.y*other.x;    // determinant
-        float angle = (float) atan2(det, dot);  // atan2(y, x) or atan2(sin, cos)
-        return angle;
-    }
-
-    float angle(){
-        return (float) atan2(y, x);
-    }
-}

src/Vector/Line.java

@@ -1,16 +1,22 @@
+package Vector;
+
+import Vector.Vector;
 import processing.core.PApplet;
 
+import java.util.ArrayList;
 import java.util.List;
 
 import static processing.core.PApplet.*;
 
-public class Line{
+public class Line implements LineInterface{
     // vector which represents  the direction and length of the line from its starting position
     protected Vector direction = new Vector(0,0);
     // store the starting position of the line
     protected Vector position = new Vector(0,0);
 
-    Line(Vector startPosition, Vector endPosition){
+    protected ArrayList<Vector> points = new ArrayList<>();
+
+    public Line(Vector startPosition, Vector endPosition){
         direction = endPosition.sub(startPosition);
         position = startPosition;
     }
@@ -19,12 +25,20 @@ public class Line{
      * attempt to find the line of best fit for the given points
      * @param points the points to get the line of best for
      */
-    Line(List<Vector> points){
+    public Line(List<Vector> points){
         bestFit(points);
     }
 
+    public void refitLine(Vector newPoint){
+        // add the new point to our list
+        this.points.add(newPoint);
+        // rerun the bestFit algorithm with the new point
+        bestFit(new ArrayList<>());
+    }
+
     // least squares line of best fit algorithm
-    private void bestFit(List<Vector> points){
+    public void bestFit(List<Vector> fitPoints){
+        this.points.addAll(fitPoints);
         // get the mean of all the points
         Vector mean = new Vector();
         for(Vector point : points){
@@ -34,26 +48,28 @@ public class Line{
 
         // this section calculates the direction vector of the line of best fit
         Vector direction = new Vector();
-        float length = 1;
+        float length = 0;
         // get the rise and run of the line of best fit
         for(Vector point : points){
             direction.y += (point.x - mean.x)*(point.y - mean.y); // rise
             direction.x += pow((point.x - mean.x),2);
 
-            // find the point that's furthest from the mean and use it to set the line length.
+            // get the average distance avery point is away from the mean.
             float dist = abs(point.sub(mean).mag());
-            if(dist > length){
+            length += dist;
-                length = 2*dist;
-            }
 
         }
+        length = 2f*length/points.size();
+        // if the direction is perfectly vertical create a line to represent that.
         if(direction.y == 0){
             this.direction = new Vector(0, 1);
         }
         else{
             this.direction = new Vector(1, direction.y/direction.x);
         }
+        // scale the direction vector to be the correct length of the line.
         this.direction = this.direction.normalize().mul(length);
+
         this.position = mean.sub(this.direction.div(2));
     }
 
@@ -75,22 +91,24 @@ public class Line{
         return direction.mag();
     }
 
-    public void draw(PApplet screen){
-        Vector endPoint = this.position.add(this.direction);
-        screen.line(position.x, position.y, endPoint.x, endPoint.y);
-    }
-
     public float getAngle(){return atan2(this.direction.y, this.direction.x);}
 
     public Vector endPoint(){
         return this.position.add(this.direction);
     }
 
-    /**
-     * @param point
-     * @return the smallest distance from the point to this line
-     */
     public float getDistance(Vector point){
-        return (point.sub(position).cross(direction)).mag() / direction.mag();
+        float line_dist = direction.mag();
+        if(line_dist == 0) return this.position.sub(point).mag();
+
+        Vector l2 = this.endPoint();
+        float t = ((point.x - position.x) * (l2.x - position.x) + (point.y - position.y) * (l2.y - position.y) + (point.z - position.z) * (l2.z - position.z)) / line_dist;
+        t = constrain(t, 0, 1);
+        Vector closestPoint = new Vector(position.x + t * (l2.x - position.x), position.y + t * (l2.y - position.y), position.z + t * (l2.z - position.z));
+        return closestPoint.sub(point).mag();
+    }
+
+    public void draw(PApplet proc){
+        proc.line(position.x, position.y, endPoint().x, endPoint().y);
     }
 }

src/Vector/LineInterface.java

@@ -0,0 +1,20 @@
+package Vector;
+
+import processing.core.PApplet;
+
+public interface LineInterface {
+    Vector getDirection();
+
+    Vector getPosition();
+
+    float getLength();
+
+    float getAngle();
+
+    Vector endPoint();
+
+    float getDistance(Vector point);
+
+    void draw(PApplet proc);
+
+}

src/Vector/Vector.java

@@ -0,0 +1,135 @@
+package Vector;
+
+import org.ejml.simple.SimpleMatrix;
+import processing.core.PApplet;
+
+import static java.lang.Math.*;
+import static processing.core.PApplet.cos;
+import static processing.core.PApplet.sin;
+
+public class Vector {
+    public float x = 0;
+    public float y = 0;
+    public float z = 0;
+
+    Vector(){}
+    public Vector(float x, float y){
+        this.x = x;
+        this.y = y;
+    }
+    
+    public Vector(float x, float y, float z){
+        this.x = x;
+        this.y = y;
+        this.z = z;
+    }
+
+    public Vector(double x, double y){
+        this.x = (float)x;
+        this.y = (float)y;
+    }
+
+    public Vector(double x, double y, double z){
+        this.x = (float)x;
+        this.y = (float)y;
+        this.z = (float)z;
+    }
+
+    public Vector(SimpleMatrix matrix){
+        // initialize x,y if matrix is 2x1 and x,y,z if matrix is 3x1
+        if(matrix.getNumRows() == 2){
+            this.x = (float)matrix.get(0,0);
+            this.y = (float)matrix.get(1,0);
+        }else if(matrix.getNumRows() == 3){
+            this.x = (float)matrix.get(0,0);
+            this.y = (float)matrix.get(1,0);
+            this.z = (float)matrix.get(2,0);
+        }
+    }
+    
+    public Vector add(Vector other){
+        return new Vector(this.x + other.x, this.y + other.y, this.z + other.z);
+    }
+
+    public Vector add(float x, float y){
+        return new Vector(this.x + x, this.y + y);
+    }
+
+    public Vector add(float x, float y, float z){
+        return new Vector(this.x + x, this.y + y, this.z + z);
+    }
+    
+    public Vector sub(Vector other){
+        return new Vector(this.x - other.x, this.y - other.y, this.z - other.z);
+    }
+
+    public Vector sub(float x, float y){
+        return new Vector(this.x - x, this.y - y);
+    }
+
+    public Vector sub(float x, float y, float z){
+        return new Vector(this.x - x, this.y - y, this.z - z);
+    }
+    
+    public Vector mul(float scalar){
+        return new Vector(this.x * scalar, this.y * scalar, this.z * scalar);
+    }
+    
+    public Vector div(float scalar){
+        return mul(1/scalar);
+    }
+    
+    public float mag(){
+        return (float)sqrt(x*x + y*y + z*z);
+    }
+
+    public float dot(Vector other){
+        return x * other.x + y * other.y + z * other.z;
+    }
+
+    public Vector cross(Vector other){
+        return new Vector(this.y*other.z - this.z*other.y, this.z*other.x - this.x*other.z, this.x*other.y - this.y*other.x);
+    }
+
+    public Vector normalize(){
+        float mag = this.mag();
+        return new Vector(x / mag, y / mag, z / mag);
+    }
+
+    /**
+     * @param other
+     * @return
+     */
+    public float angleDiff(Vector other){
+        float dot = this.dot(other);     // dot product
+        float det = this.x*other.y - this.y*other.x;    // determinant
+        float angle = (float) atan2(det, dot);  // atan2(y, x) or atan2(sin, cos)
+        return angle;
+    }
+
+    /**
+     * @return The angle of the vector in radians
+     */
+    public float angle(){
+        return (float) atan2(y, x);
+    }
+
+    /**
+     * @brief Rotate a 2D vector by a given angle
+     * @param angle The angle to rotate the vector by in radians
+     * @return The rotated vector
+     */
+    public Vector rotate2D(float angle){
+        float distance = mag();
+        float currentAngle = this.angle();
+        return new Vector(cos(currentAngle + angle), sin(currentAngle + angle)).mul(distance);
+    }
+
+    public void draw(PApplet proc){
+        proc.circle(this.x, this.y, 8);
+    }
+
+    public float[] toArray() {
+        return new float[]{x, y};
+    }
+}

src/View.java

@@ -1,20 +1,26 @@
+import Graph.PointGraph;
+import Vector.Vector;
 import processing.core.*;
 import java.util.ArrayList;
-import java.util.Objects;
+import ScanGraph.ScanPoint;
-
-import static processing.core.PApplet.*;
 
 public class View {
-    Vector pose;
+    Vector position;
     float angle = 0;
     float FOV;
     ArrayList<Ray> rays = new ArrayList<>();
     private static PApplet proc;
 
-    //the x,y position of the view, what angle it's looking at and its FOV
+    /**
+     * @brief Constructor for the View class
+     * @param processing The PApplet that the view will be drawn on
+     * @param newPose The position of the view
+     * @param numberOfRays The number of rays that the view will have
+     * @param FOV The field of view of the view
+     */
     View(PApplet processing, Vector newPose, int numberOfRays, float FOV) {
         proc = processing;
-        this.pose = newPose;
+        this.position = newPose;
         this.FOV = FOV;
         this.setRayNum(numberOfRays, FOV, this.angle);
     }
@@ -23,34 +29,48 @@ public class View {
     public void setRayNum(int numberOfRays, float FOV, float angleOffset) {
         float rayStep = FOV / numberOfRays;
         rays.clear();
-        float angle = (float) (0.01 - angleOffset); //the 0.01 fixes some bugs
+        float angle = (float) (angleOffset); //the 0.01 fixes some bugs
         for (int i = 0; i < numberOfRays; i++) {
-            Ray ray = new Ray(pose, angle);
+            Ray ray = new Ray(position, angle);
             angle = angle + rayStep;
             rays.add(ray);
         }
     }
 
-    //sees if the ray will collide with the walls in the wall list
+    /**
-    public void look(ArrayList<Wall> walls) {
+     * @brief Calculates the points of intersection of the rays with the map
+     * @param map The map that the view is looking at
+     */
+    public void calculatePointScan(PointGraph map) {
         for (Ray ray : rays) {
-            ray.castRay(walls);
+            ray.castRay(map);
-            ray.drawRay(proc);
+            if(ray.hasCollided()){
+                ray.getPoint().draw(proc);
+            }
         }
     }
 
-    //changes the position of the view
+    /**
-    public void setPos(Vector newPose) {
+     * @brief Sets the position of the view
-        pose = newPose;
+     * @param newPosition The new position of the view
+     */
+    public void setPos(Vector newPosition) {
+        position = newPosition;
         for (Ray ray : rays) {
-            ray.setPos(pose);
+            ray.setPos(position);
         }
     }
 
-    //changes the angle of the view
+    /**
-    public void setAngle(float angle) {
+     * @brief Sets the angle of the view
-        this.angle = angle;
+     * @param newAngle The new angle of the view
-        this.setRayNum(rays.size(), this.FOV, angle);
+     */
+    public void setAngle(float newAngle) {
+        this.angle = newAngle;
+        for(Ray ray : rays){
+            float angleOffset = ray.getAngle() - this.angle;
+            ray.setAngle(this.angle+angleOffset);
+        }
     }
 
     //changes the field of view of the view
@@ -59,33 +79,63 @@ public class View {
         this.setRayNum(this.rays.size(), this.FOV, this.angle);
     }
 
+    /**
+     * @return The position of the view
+     */
     public Vector getPos() {
-        return pose;
+        return position;
     }
 
+    /**
+     * @return The angle of the view
+     */
     public float getAngle() {
         return this.angle;
     }
 
+    /**
+     * @return The field of view of the view
+     */
     public float getFOV() {
         return this.FOV;
     }
 
+    /**
+     * @return The number of rays that the view has
+     */
     public int getRayNum() {
         return this.rays.size();
     }
 
-    //gets the point that each ray has collided with
+    /**
-    public ArrayList<Vector> getPoints() {
+     * @brief Get the most recent scan from the view
+     * @return A ScanPoint object containing the position, angle and points of the view
+     */
+    public ScanPoint getScan() {
         ArrayList<Vector> points = new ArrayList<>();
 
         for (Ray ray : rays) {
-            if (!Objects.equals(ray.getPoint(), new Vector(0, 0) {
+            if(ray.hasCollided()){
-            })) {
+                Vector point = ray.getPoint();
-                points.add(ray.getPoint());
+                // store the angle information for that point in the z coordinate
+                point.z = ray.getAngle();
+                points.add(point);
             }
         }
-        return points;
+        return new ScanPoint(this.position,this.angle, points);
+    }
+
+    /**
+     * @return A list of the angles where a collision was detected
+     */
+    public ArrayList<Float> getAngles(){
+        ArrayList<Float> angles = new ArrayList<>();
+        for (Ray ray : rays) {
+            if (ray.hasCollided()){
+                angles.add(ray.getAngle());
+            }
+        }
+        return angles;
     }
 }
 

src/Wall.java

@@ -1,39 +0,0 @@
-import processing.core.*;
-
-import static processing.core.PApplet.*;
-
-public class Wall extends Line{
-    int r;
-    int g;
-    int b;
-
-    private final PApplet proc;
-
-    Wall(PApplet proc, Vector pos, float angle, int wallLength){
-        super(pos, (new Vector(cos(angle), sin(angle)).mul(wallLength)).add(pos));
-        this.proc = proc;
-        r = (int)proc.random(50, 255);
-        g = (int)proc.random(50, 255);
-        b = (int)proc.random(50, 255);
-    }
-
-    Wall(PApplet proc, Vector startPos, Vector endPos){
-        super(startPos, endPos);
-        this.proc = proc;
-        r = (int)proc.random(50, 255);
-        g = (int)proc.random(50, 255);
-        b = (int)proc.random(50, 255);
-    }
-
-    void drawWall(){
-        proc.stroke(r,g,b);
-        proc.strokeWeight(10);
-        proc.circle(position.x, position.y, 10);
-        proc.strokeWeight(2);
-        proc.line(position.x, position.y, position.x + direction.x, position.y + direction.y);
-    }
-
-    Vector getPos(){
-        return position;
-    }
-}

tests/LineTest.java

@@ -1,8 +1,8 @@
+import Vector.Vector;
+import Vector.Line;
 import org.junit.jupiter.api.Test;
-import processing.core.PApplet;
 
 import java.util.ArrayList;
-import java.util.List;
 import java.util.Random;
 
 import static java.lang.Math.abs;
@@ -83,20 +83,4 @@ class LineTest{
         assertFloatEquals(v1.y, line.getPosition().y);
     }
 
-    @Test
-    public void testAngle(){
-        Line ray = new Line(new Vector(680, 560), new Vector(680+116, 560+1));
-        Line wall = new Line(new Vector(675, 587), new Vector(675-114, 587-29));
-
-
-        float angle1 = wall.position.sub(ray.position).angle();
-        float angle2 = wall.endPoint().sub(ray.position).angle();
-        float rayAngle = ray.direction.angle();
-
-        System.out.println("Angle 1: " + String.valueOf(angle1) + ", Angle 2: " + String.valueOf(angle2) + ", Ray Angle: " + String.valueOf(rayAngle));
-        assertFloatEquals(1.753907144057f, angle1, 0.001f);
-        assertFloatEquals(3.1583977941048f, angle2, 0.001f);
-        assertFloatEquals(0.0086204761121f, rayAngle, 0.001f);
-    }
-
 }

tests/MatcherVisualizer.java

@@ -0,0 +1,123 @@
+import ScanGraph.ScanMatcher;
+import ScanGraph.ScanPoint;
+import Vector.Vector;
+import processing.core.PApplet;
+
+import java.util.ArrayList;
+
+public class MatcherVisualizer extends PApplet{
+
+    public static PApplet processing;
+    ScanPoint referenceScan;
+    ScanPoint scanToMatch;
+    ScanPoint scanBeingMatched;
+
+    public static void main(String[] args) {
+        PApplet.main("MatcherVisualizer");
+    }
+
+    public void settings(){
+        processing = this;
+        size(1000, 1000);
+        float connectingAngle = (float) (3 * Math.PI / 9);
+
+        // generate two scans rotated by 45 degrees and append them together
+        Vector descriptor = new Vector(200, 200);
+        Vector position = new Vector(500, 500);
+        ScanPoint scan1 = generateScanPoint(position, descriptor, 12);
+        ScanPoint scan2 = generateScanPoint(position, descriptor.rotate2D(connectingAngle), 12);
+        Vector p1 = scan1.getPoints().get(11);
+        Vector p2 = scan2.getPoints().get(11);
+        ScanPoint scan3 = generateScanPoint(p1, p2.sub(p1), 12);
+        this.referenceScan = appendScanPoints(scan1, scan2);
+        this.referenceScan = appendScanPoints(this.referenceScan, scan3);
+
+        // generate two scans offset by some amount and rotated by 55 degrees and append them together
+        Vector rotated = descriptor.rotate2D((float) Math.PI);
+        Vector offset = new Vector(100, 150);
+        ScanPoint scan4 = generateScanPoint(position.add(offset), rotated, 12);
+        ScanPoint scan5 = generateScanPoint(position.add(offset), rotated.rotate2D(connectingAngle), 12);
+        p1 = scan4.getPoints().get(11);
+        p2 = scan5.getPoints().get(11);
+        ScanPoint scan6 = generateScanPoint(p1, p2.sub(p1), 12);
+        this.scanToMatch = appendScanPoints(scan4, scan5);
+        this.scanToMatch = appendScanPoints(this.scanToMatch, scan6);
+        this.scanBeingMatched = new ScanPoint(this.scanToMatch);
+    }
+    public void draw(){
+        iterativeScanMatch();
+//        background(0);
+    }
+
+    /**
+     * @brief Generate a scan point from a scan description
+     * @param offset The offset of the scan point from the origin
+     * @param scanDescription A vector which describes the length of the line and direction of the line
+     * @return A scan point with the given offset and scan description
+     */
+    public static ScanPoint generateScanPoint(Vector offset, Vector scanDescription, int numPoints){
+        // generate a scan point with the given offset and scan description
+        ArrayList<Vector> scan = new ArrayList<>();
+
+        // divide the scan description by the number of points to allow us to scale it back up in the loop
+        Vector directionVector = scanDescription.div(numPoints-1);
+
+        for (int i = 0; i < numPoints; i++) {
+            scan.add(offset.add(directionVector.mul(i)));
+        }
+
+        return new ScanPoint(new Vector(0, 0), 0, scan);
+    }
+
+    /**
+     * @brief Append two scan points together
+     * @param scan1 The first scan point to append
+     * @param scan2 The second scan point to append
+     * @return A scan point that is the combination of the two scan points
+     */
+    public static ScanPoint appendScanPoints(ScanPoint scan1, ScanPoint scan2){
+        ArrayList<Vector> points = new ArrayList<>();
+        points.addAll(scan1.getPoints());
+        points.addAll(scan2.getPoints());
+        return new ScanPoint(new Vector(0, 0), 0, points);
+    }
+
+    /**
+     * @brief Draw a scan point to the screen
+     * @param scan The scan point to draw
+     * @param color The color to draw the scan point
+     */
+    public void drawScan(ScanPoint scan, int[] color) {
+        processing.stroke(color[0], color[1], color[2]);
+        processing.fill(color[0], color[1], color[2]);
+        ArrayList<Vector> points = scan.getPoints();
+        for (int i = 0; i < points.size() - 1; i++) {
+            Vector point = points.get(i);
+            processing.ellipse(point.x, point.y, 5, 5);
+        }
+    }
+
+    public void iterativeScanMatch() {
+        background(0);
+        int[] red = {255, 0, 0};
+        int[] green = {0, 255, 0};
+        int[] blue = {0, 0, 255};
+
+
+
+        drawScan(this.referenceScan, red);
+        drawScan(this.scanToMatch, green);
+
+        // do a single scan match and calculate the error
+        ScanMatcher matcher = new ScanMatcher();
+        matcher.calculateRotationAndTranslationMatrices(this.referenceScan, this.scanBeingMatched);
+        this.scanBeingMatched = matcher.applyRotationAndTranslationMatrices(this.scanBeingMatched);
+        float error = matcher.getError(this.referenceScan, this.scanBeingMatched);
+        drawScan(this.scanBeingMatched, blue);
+
+        // do an iterative scan match and calculate the error
+//        ScanPoint matchedScan = matcher.iterativeScanMatch(scan1, scan2, 0.01f, 10);
+
+//        float iterativeScanMatchError = matcher.getError(scan1, matchedScan);
+    }
+}

tests/ScanMatcherTest.java

@@ -0,0 +1,129 @@
+import ScanGraph.ScanMatcher;
+import ScanGraph.ScanPoint;
+import org.junit.Before;
+import org.junit.jupiter.api.BeforeEach;
+import processing.core.PApplet;
+
+import org.junit.jupiter.api.Test;
+import Vector.Vector;
+
+import java.util.ArrayList;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static processing.core.PApplet.main;
+
+class ScanMatcherTest{
+    /**
+     * @brief Generate a scan point from a scan description
+     * @param offset The offset of the scan point from the origin
+     * @param scanDescription A vector which describes the length of the line and direction of the line
+     * @return A scan point with the given offset and scan description
+     */
+    public ScanPoint generateScanPoint(Vector offset, Vector scanDescription, int numPoints){
+        // generate a scan point with the given offset and scan description
+        ArrayList<Vector> scan = new ArrayList<>();
+
+        // divide the scan description by the number of points to allow us to scale it back up in the loop
+        Vector directionVector = scanDescription.div(numPoints-1);
+
+        for (int i = 0; i < numPoints; i++) {
+            scan.add(offset.add(directionVector.mul(i)));
+        }
+
+        return new ScanPoint(new Vector(0, 0), 0, scan);
+    }
+
+    /**
+     * @brief Append two scan points together
+     * @param scan1 The first scan point to append
+     * @param scan2 The second scan point to append
+     * @return A scan point that is the combination of the two scan points
+     */
+    public ScanPoint appendScanPoints(ScanPoint scan1, ScanPoint scan2){
+        ArrayList<Vector> points = new ArrayList<>();
+        points.addAll(scan1.getPoints());
+        points.addAll(scan2.getPoints());
+        return new ScanPoint(new Vector(0, 0), 0, points);
+    }
+
+    @Test
+    public void applyRotationAndTranslationMatrices() {
+        // generate one scan that is level and another that is rotated 45 degrees.
+        Vector scanDescription = new Vector(10, 0);
+        ScanPoint referenceScan = generateScanPoint(new Vector(0, 0), scanDescription, 10);
+        ScanPoint newScan = generateScanPoint(new Vector(0, 0), scanDescription.rotate2D((float) Math.PI / 4), 10);
+
+        // calculate the rotation and translation matrices between the two scans
+        ScanMatcher matcher = new ScanMatcher();
+        matcher.calculateRotationAndTranslationMatrices(referenceScan, newScan);
+        // apply the rotation and translation matrices to the new scan
+        ScanPoint newScanWithRotationAndTranslation = matcher.applyRotationAndTranslationMatrices(newScan);
+
+        // Get the first and last points of the new scan with rotation and translation and calculate the angle between them
+        ArrayList<Vector> points = newScanWithRotationAndTranslation.getPoints();
+        Vector firstPoint = points.get(0);
+        Vector lastPoint = points.get(points.size() - 1);
+        Vector rotatedDirection = lastPoint.sub(firstPoint);
+        float angle = scanDescription.angleDiff(rotatedDirection);
+
+        // The angle between the first and last points should be zero
+        assertEquals(0, angle);
+    }
+
+    @Test
+    public void getError() {
+        // generate two scans that are the same. The error should be zero.
+        ScanPoint scan1 = generateScanPoint(new Vector(0, 0), new Vector(10, 10), 12);
+        ScanPoint scan2 = generateScanPoint(new Vector(0, 0), new Vector(10, 10), 12);
+        ScanMatcher matcher = new ScanMatcher();
+        matcher.calculateRotationAndTranslationMatrices(scan1, scan2);
+        assertEquals(0, matcher.getError(scan1, scan2));
+
+        // generate two scans that are the same but one is offset by 10 in the y direction. The error should be 10.
+        scan1 = generateScanPoint(new Vector(0, 0), new Vector(10, 10), 12);
+        scan2 = generateScanPoint(new Vector(0, 10), new Vector(10, 10), 12);
+        matcher.calculateRotationAndTranslationMatrices(scan1, scan2);
+        assertEquals(10, matcher.getError(scan1, scan2));
+
+        // generate two scans that are the same but one is rotated by 45 degrees. The error should be near zero.
+        scan1 = generateScanPoint(new Vector(0, 0), new Vector(10, 10), 12);
+        scan2 = generateScanPoint(new Vector(0, 0), new Vector(10, 10).rotate2D((float) Math.PI / 4), 12);
+        matcher.calculateRotationAndTranslationMatrices(scan1, scan2);
+        assertEquals(0, matcher.getError(scan1, scan2), 0.1);
+    }
+
+    @Test
+    public void iterativeScanMatch() {
+        float bendAngle = (float) (5 * Math.PI / 9);
+        // generate two scans rotated by 45 degrees and append them together
+        ScanPoint scan1 = generateScanPoint(new Vector(0, 0), new Vector(10, 10), 12);
+        ScanPoint scan2 = generateScanPoint(new Vector(0, 0), new Vector(10, 10).rotate2D(bendAngle), 12);
+        ScanPoint scan3 = appendScanPoints(scan1, scan2);
+
+
+        // generate two scans offset by some amount and rotated by 55 degrees and append them together
+        Vector rotated = (new Vector(10, 10)).rotate2D((float) Math.PI);
+        ScanPoint scan4 = generateScanPoint(new Vector(10, 10), rotated, 12);
+        ScanPoint scan5 = generateScanPoint(new Vector(10, 10), rotated.rotate2D(bendAngle), 12);
+        ScanPoint scan6 = appendScanPoints(scan4, scan5);
+
+
+        // do a single scan match and calculate the error
+        ScanMatcher matcher = new ScanMatcher();
+        matcher.calculateRotationAndTranslationMatrices(scan3, scan6);
+        ScanPoint oneCalcMatch = matcher.applyRotationAndTranslationMatrices(scan6);
+        float singleScanMatchError = matcher.getError(scan3, oneCalcMatch);
+
+
+        // do an iterative scan match and calculate the error
+        ScanPoint matchedScan = matcher.iterativeScanMatch(scan1, scan2, 0.0001f, 10);
+
+        // if it's null something has gone wrong with the algorithm because these scans can easily be matched.
+        assertNotNull(matchedScan);
+
+        float iterativeScanMatchError = matcher.getError(scan1, matchedScan);
+
+        // the iterative scan match should have a lower error than the single scan match
+        assertTrue(iterativeScanMatchError < singleScanMatchError);
+    }
+}

tests/VectorTest.java

@@ -1,5 +1,5 @@
+import Vector.Vector;
 import org.junit.jupiter.api.Test;
-import processing.core.PApplet;
 
 import static java.lang.Math.*;
 import static org.junit.jupiter.api.Assertions.*;
@@ -28,8 +28,8 @@ class VectorTest{
                 assertFloatEquals((float)sqrt(x2*x2 + y2*y2), v2.mag());
 
                 // test dot product
-                assertFloatEquals((float)(x1*x2+y1*y2), v1.dot(v2));
+                assertFloatEquals((x1*x2+y1*y2), v1.dot(v2));
-                assertFloatEquals((float)(x1*x2+y1*y2), v2.dot(v1));
+                assertFloatEquals((x1*x2+y1*y2), v2.dot(v1));
 
                 // test addition
                 Vector vSum = v1.add(v2);