Aufgabe 4.3 - hitsStone, reflectOnStone

src/break_out/model/Ball.java

@@ -2,7 +2,8 @@ package break_out.model;
 
 import break_out.Constants;
 
-import java.awt.Color;
+import java.awt.*;
+import java.util.ArrayList;
 import java.util.Random;
 
 /**
@@ -32,6 +33,11 @@ public class Ball implements IBall {
 	 */
 	private Color color = Constants.COLOR_COMPONENT;
 
+	/**
+	 * The stone which has been hit by the ball
+	 */
+	private Stone hitStone = null;
+
 	/**
 	 * The constructor of a ball
 	 * The balls position and direction are initialized here.
@@ -239,4 +245,128 @@ public class Ball implements IBall {
 		this.direction.setDy(reflectionVector.getDy());
 	}
 
+	/**
+	 * tests whether the ball touches any stone's hit box
+	 * @param stones
+	 * @return true if the ball touches a stone
+	 */
+	public boolean hitsStone(ArrayList<Stone> stones) {
+		// ball as a Rectangle
+		Rectangle rectBall = new Rectangle((int) getPosition().getX(), (int) getPosition().getY(), Constants.BALL_DIAMETER, Constants.BALL_DIAMETER);
+
+		// size of grid blocks
+		int blockWidth = Constants.SCREEN_WIDTH / Constants.SQUARES_X;
+		int blockHeight = Constants.SCREEN_HEIGHT / Constants.SQUARES_Y;
+
+		// foreach stone in stones
+		for(Stone stone : stones) {
+			if(stone != null) {
+				// stone as a Rectangle based on view.Field
+				Rectangle rectStone = new Rectangle((int) stone.getPosition().getX()+1, (int) stone.getPosition().getY()+1, blockWidth-1, blockHeight-1);
+
+				// if ball intersects with stone which is existent and visible
+				if(rectBall.intersects(rectStone) && stone.getColor() != null) {
+					// set stone and return true
+					hitStone = stone;
+
+					// reflect ball
+					reflectOnStone(hitStone);
+
+					return true;
+				}
+			}
+		}
+		return false;
+	}
+
+	/**
+	 * returns the stone which got hit, can be null
+	 * @return
+	 */
+	public Stone getHitStone() {
+		return hitStone;
+	}
+
+	/**
+	 * Ball got hit by Stone stone
+	 * @param stone hitbox mechanism of stone
+	 */
+	public void reflectOnStone(Stone stone) {
+		// reflection model based on view.Field rendering model
+
+		// size of grid blocks
+		int blockWidth = Constants.SCREEN_WIDTH / Constants.SQUARES_X;
+		int blockHeight = Constants.SCREEN_HEIGHT / Constants.SQUARES_Y;
+
+		// ball as a Rectangle
+		Rectangle rectBall = new Rectangle((int) getPosition().getX(), (int) getPosition().getY(), Constants.BALL_DIAMETER, Constants.BALL_DIAMETER);
+
+		// stone as a Rectangle
+		Rectangle rectStone = new Rectangle((int) stone.getPosition().getX()+1, (int) stone.getPosition().getY()+1, blockWidth-1, blockHeight-1);
+
+		// stones borders as Rectangle's
+		Rectangle topBorder = new Rectangle((int) stone.getPosition().getX(), (int) stone.getPosition().getY(), blockWidth, 1);
+		Rectangle bottomBorder = new Rectangle((int) stone.getPosition().getX(), (int) stone.getPosition().getY()+blockHeight, blockWidth, 1);
+		Rectangle leftBorder = new Rectangle((int) stone.getPosition().getX(), (int) stone.getPosition().getY(), 1, blockHeight);
+		Rectangle rightBorder = new Rectangle((int) stone.getPosition().getX()+blockWidth, (int) stone.getPosition().getY(), 1, blockHeight);
+
+		//System.out.println(String.format("ball (%s, %s) stone (%s, %s)", getPosition().getX(), getPosition().getY(), stone.getPosition().getX(), stone.getPosition().getY()));
+
+		// if stone intersects with any bounds
+		if(rectBall.intersects(rectStone.getBounds())) {
+
+			// corner intersections
+			if((rectBall.intersects(leftBorder) || rectBall.intersects(rightBorder)) && (rectBall.intersects(topBorder) || rectBall.intersects(bottomBorder))) {
+				// intersections as Rectangle's
+				Rectangle intersTop = rectBall.intersection(topBorder);
+				Rectangle intersBottom = rectBall.intersection(bottomBorder);
+				Rectangle intersLeft = rectBall.intersection(leftBorder);
+				Rectangle intersRight = rectBall.intersection(rightBorder);
+
+				// rectangles as area to determine corner
+				double areaIntersTop    = intersTop.getHeight()    * intersTop.getWidth();
+				double areaIntersBottom = intersBottom.getHeight() * intersBottom.getWidth();
+				double areaIntersLeft   = intersLeft.getHeight()   * intersLeft.getWidth();
+				double areaIntersRight  = intersRight.getHeight()  * intersRight.getWidth();
+
+				//System.out.printf("ut, ub, ul, ur: %s %s %s %s\r\n", areaIntersTop, areaIntersBottom, areaIntersLeft, areaIntersRight);
+
+				// top side
+				if(areaIntersTop > 0) {
+					// left|right border
+					if(areaIntersLeft > areaIntersTop || areaIntersRight > areaIntersTop) direction.setDx(-getDirection().getDx());
+
+					// top border
+					else direction.setDy(-getDirection().getDy());
+				}
+
+				// bottom side
+				if(areaIntersBottom > 0) {
+					// left|right border
+					if(areaIntersLeft > areaIntersBottom || areaIntersRight > areaIntersBottom) direction.setDx(-getDirection().getDx());
+
+					// bottom border
+					else direction.setDy(-getDirection().getDy());
+				}
+
+				// return; intersection already handled
+				return;
+			}
+
+			// vertical bounds
+			if(rectBall.intersects(leftBorder) || rectBall.intersects(rightBorder)) {
+				//System.out.println("left|right border");
+				direction.setDx(-getDirection().getDx());
+			}
+
+			// horizontal bounds
+			if(rectBall.intersects(topBorder) || rectBall.intersects(bottomBorder)) {
+				//System.out.println("top|bottom border");
+				direction.setDy(-getDirection().getDy());
+			}
+
+		}
+
+	}
+
 }

src/break_out/model/Level.java

@@ -152,6 +152,11 @@ public class Level extends Thread implements ILevel {
 					getBall().newRandomColor();
 				}
 
+				// Call here the balls method for reacting on stones of the playground
+				if(getBall().hitsStone(getStones())) {
+
+				}
+
 				// update paddles position
 				getPaddleTop().updatePosition(getBall());
 				getPaddleBottom().updatePosition(getBall());