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Working on 3D.

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Andrew Lawson Andrew Lawson
Andrew Lawson authored and Andrew Lawson committed Dec 3, 2014
1 parent 4dd14dc commit 0b66840bad028c82bff5d5e36a4cd0a2769f9472
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Showing with 195 additions and 43 deletions.
  1. +4 −17 README.md
  2. +191 −26 geometric_separators.pde
21 README.md
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@@ -1,24 +1,11 @@
Geometric Separators and the Parabolic Lift
geometric_separators
====================

About:
------

This Processing application is based off the paper [**Geometric Separators and the Parabolic Lift** by Don Sheehy](http://donsheehy.net/research/sheehy13geometric.pdf) and demonstrates basic usage of an algorithm (in the above paper) for finding a geometric separator for 2-D points.
Geometric separators project for CSE 4095 (Computational Geometry).

Usage:
About:
------

The application consists of a canvas and two buttons. It will allow you input a number of 2-D Euclidean points using a mouse and calculate the geometric separator. Tentatively, you will also be able to provide a file of predefined points (e.g. .csv format).

Click the mouse anywhere on the canvas to create a new input point. When you have completed your input, either press 'Reset.' to clear it or 'Calculate.' to find the separator.

Features:
---------
This Java program will allow you to input 2D

The program will visualize several components of the algorithm:

* Highlights the estimated centerpoint for your input.
* Shows the separator in relation to your input.
* Outputs the numerical information associated with the above.
* Perhaps more...
217 geometric_separators.pde
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@@ -1,6 +1,8 @@
import java.util.*;
import java.util.Map.*;
import java.lang.Boolean;
import java.util.Random;
import org.jblas.*;

int reset_x = 140;
int reset_y = 460;
@@ -12,13 +14,33 @@ int calc_y = 460;
int calc_w = 100;
int calc_h = 25;

int exam_x = 360;
int exam_y = 460;
int exam_w = 100;
int exam_h = 25;

PShape reset;
PShape calculate;
PShape sphere;
PShape example;
PVector centerPoint;
ArrayList<PVector> rawInput = new ArrayList<PVector>();
Comparator<PVector> compareX, compareXRev, compareY, compareYRev;

PShape exampleSphere;
PVector exampleCenterPoint;

ArrayList<PVector> exampleList = new ArrayList<PVector>();
PVector ex1;
PVector ex2;
PVector ex3;
PVector ex4;
PVector ex5;
PVector ex6;
PVector ex7;
PVector ex8;
PVector ex9;

// Triple used for returning three items
private class ReturnTriple {
public float sum;
@@ -48,6 +70,8 @@ void setup() {
// Create buttons
reset = createShape(RECT, reset_x, reset_y, reset_w, reset_h);
calculate = createShape(RECT, calc_x, calc_y, calc_w, calc_h);
example = createShape(RECT, exam_x, exam_y, exam_w, exam_h);
//
sphere = null;
noLoop();
compareX = new Comparator<PVector>() {
@@ -102,6 +126,16 @@ void setup() {
}
}
};
ex1 = new PVector(253, 102);
ex2 = new PVector(248, 99);
ex3 = new PVector(256, 106);
ex4 = new PVector(88, 347);
ex5 = new PVector(89, 345);
ex6 = new PVector(92, 356);
ex7 = new PVector(411, 347);
ex8 = new PVector(407, 354);
ex9 = new PVector(410, 346);
exampleList = new ArrayList<PVector>();
}

// On mouse press
@@ -111,36 +145,147 @@ void mousePressed() {
(mouseY >= reset_y && mouseY <= (reset_y + reset_h))) {
// Reset input and background
rawInput.clear();
exampleList.clear();
centerPoint = null;
sphere = null;
exampleCenterPoint = null;
exampleSphere = null;
}
// If mouse presses calculate button
else if ((mouseX >= calc_x && mouseX <= (calc_x + calc_w)) &&
(mouseY >= calc_y && mouseY <= (calc_y + calc_h))) {
// Run algorithm
CenterAndSphere returnVals = getSeparator(rawInput);
sphere = returnVals.sphere;
centerPoint = returnVals.center;
// CenterAndSphere returnVals = getSeparator(rawInput);
// sphere = returnVals.sphere;
// centerPoint = returnVals.center;
getSolution(rawInput);
}
// If example
else if ((mouseX >= exam_x && mouseX <= (exam_x + exam_w)) &&
(mouseY >= exam_y && mouseY <= (exam_y + exam_h))) {
rawInput.clear();
exampleList.add(ex1);
exampleList.add(ex2);
exampleList.add(ex3);
exampleList.add(ex4);
exampleList.add(ex5);
exampleList.add(ex6);
exampleList.add(ex7);
exampleList.add(ex8);
exampleList.add(ex9);
exampleCenterPoint = new PVector(250, 250, 20000);
CenterAndSphere example = getExample(exampleCenterPoint);
exampleSphere = example.sphere;
System.out.println(exampleSphere);
}
else {
// Create new 2D point from mouse coordinates
PVector prelim_point = new PVector(mouseX, mouseY);
// Lift to 3D with the squared magnitude of the original point
PVector final_point = new PVector(prelim_point.x, prelim_point.y,
(float)Math.pow(prelim_point.mag(), 2));
System.out.println(final_point);
rawInput.add(final_point);
}
redraw();
}

// Set solution of set of equations
void getSolution(ArrayList<PVector> input) {
System.out.println("Solver...");
// Set a to equal our points
// DenseMatrix64F a = new DenseMatrix64F(input.size(), 4);
// DenseMatrix64F b = new DenseMatrix64F(5, 1);
// DenseMatrix64F x = new DenseMatrix64F(4, 1);
float[][] aData = new float[3][input.size()];
for (int i = 0; i < input.size(); i++) {
for (int j = 0; j < 3; j++) {
switch(j) {
case 0: aData[j][i] = input.get(i).x;
break;
case 1: aData[j][i] = input.get(i).y;
break;
case 2: aData[j][i] = input.get(i).z;
break;
}
}
}
FloatMatrix coefficients = new FloatMatrix(aData);
System.out.println("Coeff");
for (int i = 0; i < 3; i++) {
System.out.println("Row");
for (int j = 0; j < 5; j++) {
System.out.println(coefficients.get(i,j));
}
}
FloatMatrix constants = FloatMatrix.zeros(5, 2);
FloatMatrix solution = Solve.solveLeastSquares(coefficients, constants);
System.out.println("Sol");
for (int i = 0; i < 5; i++) {
System.out.println("Row");
for (int j = 0; j < 2; j++) {
System.out.println(solution.get(i,j));
}
}
// RealMatrix coefficients = new Array2DRowRealMatrix(aData, false);
// RealVector constants = new ArrayRealVector(new double[] {1, 1, 1, 1, 1}, false);
// DecompositionSolver solver = new org.apache.commons.math3.linear.SingularValueDecomposition(coefficients).getSolver();
// RealVector solution = solver.solve(constants);
// for (int i = 0; i < input.size(); i++) {
// for (int j = 0; j < 5; j++) {
// switch(j) {
// case 0: a.set(j, i, input.get(i).x);
// break;
// case 1: a.set(j, i, input.get(i).y);
// break;
// case 2: a.set(j, i, input.get(i).z);
// break;
// case 3: a.set(j, i, 1);
// break;
// }
// System.out.println(a.get(j, i));
// }
// }
// System.out.println("Finished A.");
// // Set b to equal 0
// for (int i = 0; i < 4; i++) {
// b.set(i, 0, 0);
// }
// LinearSolver<DenseMatrix64F> solver = LinearSolverFactory.leastSquares(4, input.size());
// solver = new LinearSolverSafe<DenseMatrix64F>(solver);
// solver.solve(b, x);
// for (int i = 0; i < x.getNumElements(); i++) {
// System.out.println(x.get(i, 0));
// }
}

// Show example
CenterAndSphere getExample(PVector exampleCenterPoint) {
PVector unitVector = PVector.random3D();
//unitVector.mult(500);
unitVector.x = Math.abs(unitVector.x);
unitVector.y = Math.abs(unitVector.y);
unitVector.z = Math.abs(unitVector.z);
float radius = getRadius(exampleCenterPoint, unitVector);
System.out.println(radius);
float[] sphereAttributes = getSphereAttr(exampleCenterPoint, unitVector, radius);
PShape separator = createShape(ELLIPSE, sphereAttributes);
CenterAndSphere returnVals = new CenterAndSphere(exampleCenterPoint, separator);
return returnVals;
}

// Get geometric separator
CenterAndSphere getSeparator(ArrayList<PVector> input) {
// Algorithm
// 1. Get centerpoint
PVector centerPoint = approxCenterpoint(input);
// 2. Get random unit vector in 3D
PVector unitVector = PVector.random3D();
unitVector.mult(500);
unitVector.x = Math.abs(unitVector.x);
unitVector.y = Math.abs(unitVector.y);
unitVector.z = Math.abs(unitVector.z);
System.out.println("Unit Vector...");
System.out.println(unitVector);
// 3. Get radius
float radius = getRadius(centerPoint, unitVector);
// 4. Output sphere separator
@@ -153,8 +298,11 @@ CenterAndSphere getSeparator(ArrayList<PVector> input) {
// Get radius for our separator
float getRadius(PVector centerPoint, PVector unitVector) {
PVector centerPoint2D = new PVector(centerPoint.x, centerPoint.y);
System.out.println(centerPoint);
System.out.println(centerPoint2D);
float num = (float)Math.sqrt(Math.abs(centerPoint.z - Math.pow(centerPoint2D.mag(), 2)));
System.out.println(num);
System.out.println(unitVector.z);
return num / Math.abs(unitVector.z);
}

@@ -164,10 +312,7 @@ float[] getSphereAttr(PVector centerPoint, PVector unitVector, float radius) {
PVector centerPointCopy = new PVector(centerPoint.x, centerPoint.y);
unitVectorCopy.mult(radius);
centerPointCopy.sub(unitVectorCopy);
float x = centerPointCopy.x - radius;
float y = centerPointCopy.y - radius;
float z = centerPointCopy.z - radius;
float[] attributes = {x, y, 2 * radius, 2 * radius};
float[] attributes = {centerPointCopy.x, centerPointCopy.y, 2 * radius, 2 * radius};
return attributes;
}

@@ -180,12 +325,12 @@ PVector getGeometricMedian(ArrayList<PVector> input) {
else if (input.size() == 1) {
return input.get(0);
}
else if (input.size() == 2) {
// Nothing yet
}
else if (input.size() == 4) {
// Nothing yet
}
// else if (input.size() == 2) {
// // Nothing yet
// }
// else if (input.size() == 4) {
// // Nothing yet
// }
else {
// Get the point
HashMap<PVector, Float> total = new HashMap<PVector, Float>();
@@ -343,29 +488,49 @@ HashMap<PVector, Float> getAxisMin(ArrayList<PVector> input, boolean isY) {
// Draw
void draw() {
background(255);
// Draw center point
if (centerPoint != null) {
strokeWeight(6);
point(centerPoint.x, centerPoint.y);
System.out.println("x-coordinate: " + Float.toString(centerPoint.x));
System.out.println("y-coordinate: " + Float.toString(centerPoint.y));
}
// Draw separator sphere projected to 2D
if (sphere != null) {
strokeWeight(6);
shape(sphere);
}
if (exampleSphere != null) {
strokeWeight(6);
fill(255);
ellipseMode(CENTER);
shape(exampleSphere);
}
if (exampleCenterPoint != null) {
stroke(255, 0, 0);
strokeWeight(6);
point(exampleCenterPoint.x, exampleCenterPoint.y);
System.out.println("x-coordinate: " + Float.toString(exampleCenterPoint.x));
System.out.println("y-coordinate: " + Float.toString(exampleCenterPoint.y));
stroke(0);
}
shape(reset);
shape(calculate);
shape(example);
fill(50);
textSize(20);
text("Geometric Separators", 140, 20);
textSize(12);
text("Reset.", reset_x + 30, reset_y + 15);
text("Calculate.", calc_x + 25, calc_y + 15);
text("Example.", exam_x + 25, exam_y + 15);
// Draw input
for (PVector point : rawInput) {
strokeWeight(4);
strokeWeight(8);
point(point.x, point.y);
}
// Draw center point
if (centerPoint != null) {
strokeWeight(6);
point(centerPoint.x, centerPoint.y);
System.out.println("x-coordinate: " + Float.toString(centerPoint.x));
System.out.println("y-coordinate: " + Float.toString(centerPoint.y));
}
// Draw separator sphere projected to 2D
if (sphere != null) {
strokeWeight(6);
shape(sphere);
for (PVector point : exampleList) {
strokeWeight(8);
point(point.x, point.y);
}
}

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