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Bouncing balls at corresponding angles
By Phytrix, with 3 replies.
Last reply by Phytrix, about 12 years ago:
Great. Thanks.
Need Help Please. When i compile this it will say not a statement.
By Zaraki, with 1 reply.
Replied to by danpost, about 12 years ago:
One thing is that by naming your bullet objects with numbers, you are probably confusing the compiler (naming convension has variable names start with lowercase letters only). Another is that you do no have a field name for the bullet created in the else portion of the code.
Loading an image within a circle
By mattrayner, with 3 replies.
Last reply by robg, about 12 years ago:
For anyone that comes across this looking for the same thing, take a look at our solution here ->
Image within a circle
Solution Outline
- Created a new BufferedImage & got the Graphics2D object (The same size as the orignal image - Drew the Elipse that we wished to crop by. (In white) - Changed the Composite of the image to AlphaComposite.SrcAtop to allow us to clip any further drawing to the elipse. - Drew the original BufferedImage onto the new one Make sure to use the correct type when creating the BufferedImage, if you
Repeat Until?
By saskekun95, with 1 reply.
Replied to by danpost, about 12 years ago:
You do not need seperate methods for 'downwards' and 'upwards'. All you need is to 'turn' the actor when the proper conditions are met. The conditions to turn around at the top of the screen are (1) the y-coordinate of the actor is zero and (2) the rotation of the actor is 270. The conditions to turn around at the bottom of the screen are (1) the y-coordinate of the actor is one less than the width of the world and (2) the rotation of the actor is 90. When either set of conditions is true, turn the actor around 180 degrees.
java.lang.nullpointerException-Error
By Mepp, with 6 replies.
Last reply by davmac, about 12 years ago:
That means that 'spf' is null. It is the same problem - you are calling a method on a null reference.
HELP! Is it possible to blend classes?
By sopi, with 5 replies.
Last reply by danpost, about 12 years ago:
What I see is a class with a Counter object called 'counter' that is never anything but 'null'; and, if the public method 'activate' is ever called, will cause a NullPointerException.
atWorldEdge Method
By ar_jay0525, with 2 replies.
Last reply by Phytrix, about 12 years ago:
It'd seem that the method doesn't exist. You can use the following code for an atWorldEdge method. Replace the 10s as you wish. Generally, people want objects to bounce when the edge of it hits the very borders of the world, so I'd recommend replacing the 10s with half of the size in pixels of your image. public boolean atWorldEdge() { if(getX() < 10 || getX() > getWorld().getWidth() - 10) return true; if(getY() < 10 || getY() > getWorld().getHeight() - 10) return true; else return false; }
Can't call method from world class in actor class
By ycart, with 2 replies.
Last reply by danpost, about 12 years ago:
I am quite sure that the 'startMission' method IS working. It is only called
once
after the mouse click. Each method it calls will run
one time
. Therefore, you will have a 1 in 300 chance of one Food object appearing; a 1 in 600 chance of one Treasures object appearing; and, a 1 in 100 chance of one Person object appearing. You would be very lucky to have anything appear, which is why it seems like it is not working. I think what you wanted is that these object randomly, but continuously, appear throughout the game. In order to accomplish this, you will need a boolean fie
stops game
By aananon, with 6 replies.
Last reply by danpost, about 12 years ago:
What you need to do is either control the rotation of the object so that the call to the 'move' method will move the object in the proper direction or keep track of the speed of the object in both the x and y directions. With either method, the proper adjustments to the rotation or value of the variables are needed when the object hits the walls.
Help with exporting problem
By BradH, with 5 replies.
Last reply by BradH, about 12 years ago:
oh no sorry, i was just wondering if anyone on this website could help, nothing to do with greenfoot.
One glitch in my greeps scenario
By JHankins, with no replies.
i do not want to post my code on here is there anyone that could let me know of a way to send it for review to get some advice?
cannot find symbol - constructor...
By Mepp, with 10 replies.
Last reply by Mepp, about 12 years ago:
Thanks, It worked fine now!
SOUND AT BACKGROUND PLEASE HELP!!!!
By Prish950, with 4 replies.
Last reply by Prish950, about 12 years ago:
Thank YOU :D
Errors
By DoctorProfessorYoshi, with 3 replies.
Last reply by danpost, about 12 years ago:
Sorry, I do not know a thing about that one.
Help with code!
By JHankins, with 1 reply.
Replied to by danpost, about 12 years ago:
It appears that what your instructor gave you was pseudo-code (code written in english form -- but not actual code). You have to 'convert' it to real code that the compiler can understand. Unless you summarized your code for the discussion. If this is the case, please post the code for the class. It may be that your bracketing is off.
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