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nooby123
nooby123 wrote ...

2011/7/12

how do you make an object point away from another object?

nooby123 nooby123

2011/7/12

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im trying to make a game where an ant is chasing lots of other small and im trying to make them face away and i don't know how any ideas?
GameCode GameCode

2011/7/12

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You could take a look at the source code of my 'Catch the fly scenario' ( http://greenfootgallery.org/scenarios/3221 )
GameCode GameCode

2011/7/12

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This is the code you might be interested in. Write this in your chased Actor:
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Ant a = new Ant(); 
int x = a.getX() - getX(); 
int y = a.getY() - getY(); 
r = Math.toDegrees(Math.atan2(x, y)) - 270; 
setRotation(-(int) r); 
move(...speed...);
nooby123 nooby123

2011/7/12

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my editor says " cannot find symbol - variable r " what do i do?
GameCode GameCode

2011/7/13

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Oh sorry forgot an 'int' :
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Ant a = new Ant();   
int x = a.getX() - getX();   
int y = a.getY() - getY();   
[b]int[/b] r = Math.toDegrees(Math.atan2(x, y)) - 270;   
setRotation(-(int) r);   
move(...speed...);
GameCode GameCode

2011/7/13

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Oh sorry forgot an 'int' : view plaincopy to clipboardprint? Ant a = new Ant(); int x = a.getX() - getX(); int y = a.getY() - getY(); int r = Math.toDegrees(Math.atan2(x, y)) - 270; setRotation(-(int) r); move(...speed...);
nooby123 nooby123

2011/7/13

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my editor looks like this: Ant a = new Ant(); int x = a.getX() - getX(); int y = a.getY() - getY(); int r = Math.toDegrees(Math.atan2(x, y)) - 270; <- It says here " possible loss of precision found setRotation(-(int) r); :doublerquired: int " move(2);
GameCode GameCode

2011/7/13

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Upps, r has to be a double. so its double r = Math..........
nooby123 nooby123

2011/7/13

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soory again but this terminal error thingy keeps popping up when i press the run button and saying java.lang.IllegalStateException: The actor has not been inserted into a world so it has no location yet. You might want to look at the method addedToWorld on the Actor class. at greenfoot.Actor.failIfNotInWorld(Actor.java:659) at greenfoot.Actor.getX(Actor.java:157) at EvenSmallerAnt.turnAway(EvenSmallerAnt.java:51) at EvenSmallerAnt.act(EvenSmallerAnt.java:18) at greenfoot.core.Simulation.actActor(Simulation.java:498) at greenfoot.core.Simulation.runOneLoop(Simulation.java:461) at greenfoot.core.Simulation.runContent(Simulation.java:197) at greenfoot.core.Simulation.run(Simulation.java:187)
DonaldDuck DonaldDuck

2011/7/13

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You cannot call getX() or getY() from the constructor of an object (public ()) Move the code that uses these calls into the act method and you should be good.
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