Working version (d4c25358) · Commits · Leon Zeyu Long / hw3p2

src/edu/bu/ec504/hw3/p1/Canvas.java

+39 −9

Original line number	Diff line number	Diff line
		@@ -14,7 +14,7 @@ public abstract class Canvas implements Iterable<CanvasPoint> {
		* @param theXsize The X dimension of the support plain for points.
		* @param theYsize The Y dimension of the support plain for points.
		*/
		public Canvas(float theXsize, float theYsize) {
		public Canvas(double theXsize, double theYsize) {
		Xsize=theXsize; Ysize = theYsize;
		points = new ArrayList<>();
		}
		@@ -28,7 +28,7 @@ public abstract class Canvas implements Iterable<CanvasPoint> {
		* @note: You may want to override this method.
		*/
		public void addPoint(CanvasPoint pnt) {
		_check(pnt);
		_checkPoint(pnt);
		points.add(pnt); }

		/**
		@@ -40,7 +40,7 @@ public abstract class Canvas implements Iterable<CanvasPoint> {
		* @note: You may want to override this method.
		*/
		public boolean deletePoint(CanvasPoint pnt) {
		_check(pnt);
		_checkPoint(pnt);
		return points.remove(pnt); }

		/**
		@@ -62,18 +62,48 @@ public abstract class Canvas implements Iterable<CanvasPoint> {
		return points.iterator();
		}

		private void _check(CanvasPoint pnt) {
		/**
		*
		* @param centers
		* @return true iff unit circles centered at the points in <code>centers</code>
		* cover all the points in this data structure.
		*/
		public boolean checkCovering(ArrayList<CanvasPoint> centers) {
		// check each point, one by one
		for (CanvasPoint pnt: this) {
		boolean foundCenter = false;
		// look at each center to see if one of them is of distance <=1 from the point
		for (CanvasPoint center: centers) {
		if (_distance(center,pnt) <= 1.0f) {
		foundCenter = true;
		break;
		}
		}
		if (!foundCenter)
		return false;
		}
		return true;
		}

		private void _checkPoint(CanvasPoint pnt) {
		if ((pnt.x<0) \|\| (pnt.x>Xsize) \|\| (pnt.x<0) \|\| (pnt.y>Ysize))
		throw new RuntimeException("Point coordinates off canvas");
		}

		private double _distance(CanvasPoint pnt1, CanvasPoint pnt2) {
		return Math.sqrt(
		Math.pow(pnt1.x - pnt2.x,2) +
		Math.pow(pnt1.y - pnt2.y,2)
		);
		}

		// NESTED SUBCLASSES

		/**
		* A point on the canvas.
		*/
		public static class CanvasPoint {
		CanvasPoint(float theX, float theY) {
		CanvasPoint(double theX, double theY) {
		x = theX; y=theY;
		}

		@@ -85,13 +115,13 @@ public abstract class Canvas implements Iterable<CanvasPoint> {
		'}';
		}

		final public float x;
		final public float y;
		final public double x;
		final public double y;
		}

		// FIELDS
		protected float Xsize;
		protected float Ysize;
		protected double Xsize;
		protected double Ysize;
		protected ArrayList<CanvasPoint> points;

		}

src/edu/bu/ec504/hw3/p1/GraphicalMain.java

+2 −2

Original line number	Diff line number	Diff line
		@@ -19,8 +19,8 @@ public class GraphicalMain extends JFrame {
		final int prefY = 10;
		final int xScale = 30; // scale all X coordinates on the Canvas by this amount
		final int yScale = 30; // scale all X coordinates on the Canvas by this amount
		final float pointRad = 1f/10f; // radius of a point
		final float coverRad = 1f; // radius of a covering circle
		final double pointRad = 1d/10d; // radius of a point
		final double coverRad = 1d; // radius of a covering circle
		final Color pointCol = new Color(255,0,0,255); // color for a point
		final Color coverCol = new Color(0,0,255,50); // color for a covering circle

src/edu/bu/ec504/hw3/p1/Main.java

+16 −2

Original line number	Diff line number	Diff line
		@@ -5,15 +5,29 @@ import java.util.ArrayList;

		public class Main {

		/**
		* Run a simple test of the MyCanvas class.
		* @param baseX The x dimension of the underlying canvas.
		* @param baseY The y dimension of the underlying canvas.
		* @return A CoverResult, which contains the canvas produced and its proposed covering.
		*/
		static CoverResult testCovering(int baseX, int baseY) {
		Canvas testCanvas = new MyCanvas(baseX,baseY);
		for (int ii=0; ii<Math.min(baseX,baseY); ii++)
		testCanvas.addPoint(new CanvasPoint(ii,ii));
		return new CoverResult(testCanvas, testCanvas.generateCovering());

		// show results
		ArrayList<CanvasPoint> testCovering = testCanvas.generateCovering();
		System.out.println("Produced covering:");
		System.out.println(testCovering);
		System.out.println(" ... covering is "+(testCanvas.checkCovering(testCovering)?" valid!":" invalid"));

		// return results
		return new CoverResult(testCanvas, testCovering);
		}

		public static void main(String[] args) {
		CoverResult result = testCovering(100,100);
		System.out.println(result.centers);
		}

		static public class CoverResult {