2014/11/21
/**
* Write a description of class Crate here.
*
* @author (your name)
* @version (a version number or a date)
*/
public class Crate extends Actor
{
public Crate()
{
//when the crate is created turnh it to face the bottom of the screen
}
public void act()
{
///drop the crate
MoveRandomly moverandomly2 = new MoveRandomly(Crate);
addObject(moverandomly2, 99, 108);
}
}
import greenfoot.*;
import java.awt.Color;
/**
* <p>MoveRandomly is a class that causes an actor to move in a random way.</p>
*
* <p>The simple constructor simply calls for the actor who is moving. To use this constructor, use the
* following code at the beginning of your class:</p>
*
* <p style = "font-weight: bold">MoveRandomly moverandomly = new MoveRandomly(this);</p>
*
* <p>The advanced constructor calls for two arguments, the actor who's moving and a class that the actor
* can't move past. For example to make your actor move randomly but be stopped by the class Wall,
* use the following code: </p>
*
* <p style = "font-weight: bold">MoveRandomly moverandomly= new MoveRandomly(this, Wall.class);</p>
*
* <p>MoveRandomly has one method, moveRandomly(). This method actually causes your actor to move in a
* random way. The basic argument for moveRandomly calls for just the speed at which you want to move.
* For example, to move randomly at a speed of 5, use the following code:</p>
*
* <p style = "font-weight: bold">moverandomly.moveRandomly(5);</p>
*
* <p>The more advanced version of the moveRandomly method calls for the speed argument, an integer argument
* for turn percentage and an integer argument for turn width. The turn percentage should be a number between
* 1 and 100, and is the percent chance that the mover will change direction on any given turn. The higher
* the number, the frequently the mover will turn. The turn width is the narrowest turn the mover will take
* in degrees, so should be less than or equal to 180 (A turn width of 180 will mean the actor can only turn
* left and right; a turn width of 90 will mean the actor can only move up, down, left and right).
* To make your actor have a speed of five with 10 percent chance
* of turning and a minimum turn width of 90 degrees, use this code:</p>
*
* <p style = "font-weight: bold">moverandomly.moveRandomly(4, 10, 90);</p>
*
* @author Jim Stewart
* @version 1.0
*/
public class MoveRandomly extends Actor
{
Actor mover;
int rightSideOfScreen = 0;
int bottomOfScreen = 0;
World myWorld = null;
int turnPercentage=1;
int turnWidth =360;
Class obstacleClass = null;
int width;
int height;
int distanceToFront;
boolean blocked = false;
/**
* Constructor for objects of class MoveRandomly
*/
public MoveRandomly(Actor mover)
{
this.mover = mover;
}
public MoveRandomly(Actor mover, Class obstacleClass)
{
this.mover = mover;
this.obstacleClass = obstacleClass;
}
public void moveRandomly(int speed)
{
if(myWorld == null)
{
setWorld();
}
if(Greenfoot.getRandomNumber(100)<=5)
{
turnRandom(1);
}
int x = mover.getX();
int y = mover.getY();
if(x<=0 || y<=0 || x >= rightSideOfScreen || y >= bottomOfScreen)
{
mover.turn(180);
}
if(obstacleClass!=null)
{
if(findObstacle())
blocked =true;
else
blocked = false;
}
if(!blocked)
mover.move(10);
else
turnRandom(1);
}
public void moveRandomly(int speed, int turnPercentage, int turnWidth)
{
if(myWorld == null)
{
setWorld();
}
if (turnPercentage<=100)
this.turnPercentage=turnPercentage;
if(turnWidth<360)
this.turnWidth=turnWidth;
if(Greenfoot.getRandomNumber(100)<=turnPercentage)
{
turnRandom(this.turnWidth);
}
int x = mover.getX();
int y = mover.getY();
if(x<=0 || y<=0 || x >= rightSideOfScreen || y >= bottomOfScreen)
{
mover.turn(180);
}
if(obstacleClass!=null)
{
if(findObstacle())
blocked =true;
else
blocked = false;
}
if(!blocked)
mover.move(speed);
else
turnRandom(turnWidth);
}
private boolean findObstacle()
{
if(getWorld()==null) // If we're not in the world yet...
{
width = 10;
height = mover.getImage().getHeight(); // Set the height of the invisible sensor. This is the width of the moving actor.
distanceToFront = mover.getImage().getWidth()/2; // Set the distance to front. Half the size of the image.
mover.getWorld().addObject(this, 0, 0); // put us in the world
setImage(new GreenfootImage(width, height)); // and set our height and width.
/*
* The commented out code below can be uncommented if you want to see your sensing
* actor for some reason.
*/
//getImage().setColor(Color.RED);
//getImage().fillRect(0, 0, width-1, height-1);
}
setRotation(mover.getRotation()); //point the same direction as the mover
int xOffset =(int)Math.ceil(distanceToFront*Math.cos(Math.toRadians(mover.getRotation()))); //These three lines find a location directly in frontof the mover
int yOffset = (int)Math.ceil(distanceToFront*Math.sin(Math.toRadians(mover.getRotation())));//using trigonometry and assigns them to xOffset & yOffset variables
setLocation(mover.getX() + xOffset, mover.getY()+yOffset); //then places the actor there so it can sense for obstacles in front.
Actor obstacle = getOneIntersectingObject(obstacleClass); //This line actually finds an obstacle obstructing the mover.
return obstacle!=null;
}
private void setWorld()
{
this.myWorld = mover.getWorld();
this.rightSideOfScreen = myWorld.getWidth()-1;
this.bottomOfScreen=myWorld.getHeight()-1;
}
public void turnRandom(int turnWidth)
{
int newRot = Greenfoot.getRandomNumber(360/turnWidth)*turnWidth;
mover.turn(newRot);
}
}
MoveRandomly moverandomly2 = new MoveRandomly(Crate);
// declare instance field private MoveRandomly moverandomly; // in constructor moverandomly = new MoveRandomly(this); // in act (for example) moverandomly.moveRandomly(5);