[mx] any way of storing the current position of an object

programming flash
1

hey,

I’ve always wondered if there was a way to retrieve and store the current position of an object.

i am trying to develop a background slideshow using penners equations. but i get into trouble because you have to define the start position.

so let’s say you click button 1, and the object moves from x =0 to x = 200.

Now when i press button 2, i want the object to move from x = 200 to x = 400.

and if i then press button 4, i want it to move from x=200 to x=800 and so on.

So i need to go from the current position to any of the new positions.

i could do this simply using the normal inertia code.


this.onEnterframe = function(){
if(change ==2){
if(_x!=400){
_x +=(400 - _x)/speed;
}
}

if(change==3){
if(_x!=600){
_x +=(600 - _x)/speed;
}
}

}

With something like this, the object will move both left and right and by different amounts depending on the button pressed.

I want to do this using penner’s eqs.

Any ideas,

kd

2

um, to get the objects current x position, just type object._x

your code in AS:
[AS]
on(press){
movie._x +=200;
}
[/AS]

3

urh,

but that’s setting the _x. i want to retrieve it based on what has happened before.

Am i missing something?

4

you can set it or retrieve it. if you just want to store the value in a variable, go

[AS]
xvalue = movie._x;
[/AS]

I’m not sure i totally understand what you are asking

5

ok so an example:


dNum = 20;
tNum = 0;
endNum = -730;
//////////////////////////////

var start = strip._x;
var end = strip._x+_root.endNum;
var duration = _root.dNum;
var t = _root.tNum;
_root.Change = 0;
this.onEnterFrame = function() {
	if (_root.Change == 2) {
        if (t<=duration) {
                strip._x = Math.EaseInOutQuint(t, start, end, duration);
				t++;

        }
	}
	if (_root.Change == 3) {
        if (t<=duration) {
                strip._x = Math.EaseInOutQuint(t, start, end, duration);
				t++;

        }
	}
};
butt2.onPress = function() {
	_root.Change = 2;
	t=0;
};

butt3.onPress = function() {
	_root.Change = 3;
	t=0;
};

//strip is the instance name of the object i want to move

Crude example but:
Say i press butt2 - movie moves from x=0 to x=-730;

now say i press butt3 - i want the movie to move anothe -730 from its current position which is X=-730;

But this doesn’t happen. Instead when i press butt3, strip starts again from x=0, and moves -730 pixels.

Can you see what i mean now? I want to constantly check where the current x position is, and store that figure as a variable.

Thanks, hope you understand my ramblings!

kd

6

try this

[AS]
onClipEvent(enterFrame){
stripXPos = strip._x;
}
[/AS]

this will constantly update stipXPos to whatever the xvalue of strip is. See if this help at all.

7

hey,

That’s exactly what i was just thinking. But i still can’t get it to work.

Here is the new code:


dNum = 20;
tNum = 0;
endNum = -730;
//////////////////////////////

var start = stripXPos;
var end = stripXPos+_root.endNum;
var duration = _root.dNum;
var t = _root.tNum;
_root.Change = 0;
this.onEnterFrame = function() {
	stripXPos = strip._x;
	if (_root.Change == 2) {
        if (t<=duration) {
                strip._x = Math.EaseInOutQuint(t, start, end, duration);
				t++;

        }
	}
	if (_root.Change == 3) {
        if (t<=duration) {
                strip._x = Math.EaseInOutQuint(t, start, end, duration);
				t++;

        }
	}
};
butt2.onPress = function() {
	_root.Change = 2;
	t=0;
};

butt3.onPress = function() {
	_root.Change = 3;
	t=0;
};

I totally understand now that you need something in side the enterframe so it can constantly check the x position. But can’t figure out how to integrate it.

Any ideas? maybe you can see something wrong in the code,

Thanks for all the help so far

kd

8

you never update the value of start. You are passing it as a parameter to some function but I assume you need to update it first.