Processing 1.0 - Processing Discourse - is classes the right kind of thing to use?

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is classes the right kind of thing to use? (Read 309 times)

wiltors

is classes the right kind of thing to use?
Oct 24^th, 2008, 10:00am

I'm trying to make a game which involves creating missiles which are created at the top of the screen and travel slowly to the bottom of the screen...now that's not the problem, the problem is i want to be able to have as many of these missiles on the screen as i want, and i don't know how to go about this. does anybody have any suggestions on what to do?

rgilbank

Re: is classes the right kind of thing to use?
Reply #1 - Oct 25^th, 2008, 4:39pm

Yep, classes are the way to go. You'd need something like this:
/*
** pseudo-code only.
*/

Missile missile1;

void setup(){
missile1 = new Missile();
}

void draw(){
missile1.draw();
}

class Missile{

int yPosition=0;

Missile(){
//initializing stuff...maybe set the x position?
}
void draw(){
yPosition++;
//draw the actual missile
}
}

Hope that helps.

koogy

Re: is classes the right kind of thing to use?
Reply #2 - Oct 25^th, 2008, 11:49pm

i think the bigger problem was the 'i want to be able to have as many of these missiles on the screen as i want' which is the job for the expandable java ArrayList

List missiles = new ArrayList();

then add missiles using
missiles.add(new Missile());

the fiddly thing is to draw the list backwards

for (int i = missiles.size - 1 ; i >= 0 ; i--) {
missiles.get(i).draw();
}

so that the draw method can remove individual missiles with missiles.remove(i); (when they explode, say, or leave the screen) without affecting the indexes of the missiles yet to process.

there will, obviously, still be limits to the number of missiles on the screen because they will all take a finite time to move and draw...

http://www.anyexample.com/programming/java/java_arraylist_example.xml

rgilbank YaBB Newbies Offline Posts: 16	Re: is classes the right kind of thing to use? Reply #3 - Oct 26^th, 2008, 3:03am I was thinking of just using the class to make as many as you wanted...but that works too. Probably better actually from the looks of that remove() method

wiltors YaBB Newbies Offline Posts: 8	Re: is classes the right kind of thing to use? Reply #4 - Oct 27^th, 2008, 10:30pm thank you for the suggestions, i'll check the syntax for these commands

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