Rewind bug

Summary:

Has me stumped.

Rewind bug

Linkage2 24 Oct 2007 06:33

Ok, I've come across a weird bug with the Rewind function in my game and I don't quite get how it's going wrong.

Anyway, the problem is that when I have more than one enemy and then try to Rewind them, they all kind of join together position-wise and then start switching between each others' positions in their Rewind data. Basically, for each of them their data for where they have been is getting screwed up somehow. By outputting the Y position stored in the first part of the array at different intervals, I've pinpointed the code that's the problem, although I was pretty sure it was that anyway.

Here's the code of what I do to all the enemies each loop:

//here we adjust the enemies- all the AI stuff + scroll and check for hit with player
    for (g = 0; g < 100; g++) {
        if (enemy[g].used) {
            enemy[g].coll = false;
            if (tim_body.hitTest(enemy[g].sp)) {
                if (hurt == 0) {
                    health -= 5;
                    jumping = true;
                    dir = enemy[g].dir;
                    yVel = 10;
                    xVel = 15 * dir;
                    hurt = 50;
                }
                coll = true;
                enemy[g].coll = true;
            }

            if (tRewind > 500) {
                enemy[g].Rewind(tRewind);
            }
            if (tPause < 250) {
                enemy[g].walk(lvl);
                if (tRewind < 500) {
                    enemy[g].memorise(g);
                    //trace("Post-Memory" + g + ":" + enemy[0].rY[249]);
                }
            }

            enemy[g].sp._x += XOff;
            enemy[g].sp._y += YOff;
            enemy[g].XOff += XOff;
            enemy[g].YOff += YOff;
        }
    }

And here's the Enemy class which has the function that's the problem, memorise():

class Enemies {
    public var sp:MovieClip, used:Boolean, eType:Number, XOff:Number = 0, YOff:Number = 0;
    public var j:Number = 0;
    public var coll:Boolean = false;
    private var rX:Array = new Array(250), rY:Array = new Array(250), rF:Array = new Array(250);
    private var rD:Array = new Array(250);
    private var dir:Number = -1;

    public function Enemies(eUsed, eSp, eeType) {
        this.used = eUsed;
        this.sp = eSp;
        this.eType = eeType;
    }

    public function walk(lvl) {
        if (lvl[int((this.sp._y - this.YOff) / 50)][int((this.sp._x + (30 * this.dir) - this.XOff) / 50)] < 9 &&
            lvl[int((this.sp._y - this.YOff + this.sp._height) / 50)][int((this.sp._x + (30 * this.dir) - this.XOff) / 50)] >= 9) {

            if (!this.coll) {
                this.sp._x += 3 * this. dir;
            }
        }else {
            this.dir = -this.dir;
        }
        this.sp._xscale = 100 * this.dir;
    }

    public function memorise() {
        for (j = 0; j < 249; j++) {
            this.rX[j] = this.rX[j + 1];
            this.rY[j] = this.rY[j + 1];
            this.rF[j] = this.rF[j + 1];
            this.rD[j] = this.rD[j + 1];
        }
        this.rX[249] = this.sp._x - this.XOff;
        this.rY[249] = this.sp._y - this.YOff;
        this.rF[249] = this.sp._currentframe;
        this.rD[249] = this.dir;
    }

    public function Rewind(tRewind) {
        this.sp._x = this.rX[tRewind - 501] + this.XOff;
        this.sp._y = this.rY[tRewind - 501] + this.YOff;
        this.sp.gotoAndStop(rF[tRewind - 501]);
        this.dir = this.rD[tRewind - 501];
    }
}

From what I was outputting with the trace right after running the enemy.memorise() function, I found that the same variable of one of the enemies was coming out different after running the memorise() function of the OTHER enemy. However, since I'm using "this" with all my references (except j), I don't see how this is happening.

I also outputted all of the previous Y positions of both enemies at one point, and got this:

0:
252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352
1:
252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352,252,352

You'll notice that both of the arrays are exactly the same (although considering the Rewind results I probably should have guessed that). It's almost as though the rY, rX and so on arrays are being static, but I didn't declare them that way so I don't see why they would be.

Anyway, any help on this would be appreciated.

Re: Rewind bug

hartnell 25 Oct 2007 00:04

Ok, this is alot of info to digest. I'll get to this soon. —hartnell

Re: Rewind bug

hartnell 25 Oct 2007 00:05

I'm just waking up after a "big sleep." —hartnell

Re: Rewind bug

Linkage2 29 Oct 2007 05:09

Argh. I just did another test then where I changed the value of one of the enemies' rYs to a specific value then outputted the value of the other enemy. The change was applied to the other enemy as well!

Ok, so I think that just about proves that the arrays are acting like static ones or doing something similar. But why? I'm thinking it might be something ActionScript that I don't know yet, but I really don't get why it would be doing this.

EDIT: Just a side-note, I'm pretty sure this is something Flash will do to any Array in a class, at least with the "normal" method, rather than there being something that distinguishes my arrays from the rest.

DOUBLE EDIT: Yes! I did a Forum Search on this AS forum and found a topic that was basically exactly about my problem, and it showed how to fix it. Apparently, what you need to do is declare all the arrays like this at first:

var array:Array;

Then, in your constructor, assign them their array size and so on, like so:

function nameOfClass() {
      array = new Array(3);
}

RARRGH. I am so glad I finally got this fixed. If I weren't able to fix it, I'd probably have to cut the Rewind out of the game.

PS: I am so glad that this is fixed that I literally got up and ran around my house in joy when it worked. :) I was also busy calling Flash a retard.

Last edited on 29 Oct 2007 05:25 by Linkage2 Show more

Re: Rewind bug

u9 29 Oct 2007 19:14

I am so glad that this is fixed that I literally got up and ran around my house in joy when it worked. :) I was also busy calling Flash a retard.

This sounds even more entertaining then a good cartoon hehe… I can picture it in my head :)