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Hissss
Hissss wrote ...

2020/12/1

Having trouble with referencing actors because static/non-static issues

Hissss Hissss

2020/12/1

#
Hello, I'm fairly new to Greenfoot and have been trying to get an enemy to follow the main character, kara, when in a certain radius for the past two hours with no luck. Is there any chance someone can help me out? Here's the code for the main character that is relevant: public int returnX(){ return getX(); } public int returnY(){ return getY(); } public int returnAngle(){ return getRotation(); } And here's what I have for the enemy as of now that is relevant: public void act() { moveAndTurn(); touch(); } public void moveAndTurn(){ turnTowards​(kara.getX(), kara.getY()); move(1); } This is definitely some fundamental understanding that I don't understand so I'm hoping someone can help me out. Thanks!
danpost danpost

2020/12/1

#
Hissss wrote...
This is definitely some fundamental understanding that I don't understand so I'm hoping someone can help me out. Thanks!
A class (e.g. kara) describes an object . Any number of objects can be created from a class such as kara. These objects, when Actor objects, can have location coordinates in a world. Saying "kara.getX()" does not specify which object created from the class that you want the coordinate of. Another way to look at it is that kara is a class name -- not an Actor object and class names do not have coordinates in any world. One way to get a reference to the kara object in your world is: 
Actor k = getWorld().getObjects(kara.class).get(0);
However. you seem to require the kara object to be within some range, so you could use (replacing "<< range >>" with the proper value or variable): 
Actor k = null;
if (getObjectsInRange(<< range >>, kara.class).size()  > 0)
{
    k = getObjectsInRange(<< range >>, kara.class).get(0);
}
if (k != null)
{
    // put follow code here
}
You can now get the coordinates of the kara object for the follow codes with this: 
int karaX = k.getX();
int karaY = k.getY();
Hissss Hissss

2020/12/1

#
I saw you in a bunch of other posts and want to thank you so much for the speedy reply! I have a major progress check due tomorrow and you saved my life! Thank you so much Mr. Danpost! I can't imagine how many other people you helped save and hope this message goes to heart because I'll likely be needing your help some more sometime in the future.
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