random motion

[gerbick]

there HAS to be a quicker way to get random movement.

function getdistance (x, y, x1, y1) {
	var run, rise;
	run = x1-x;
	rise = y1-y;
	return (hyp(run, rise));
}
function hyp (a, b) {
	return (Math.sqrt(a*a+b*b));
}
MovieClip.prototype.reset = function () { 
var dist, norm, movie_height, movie_width;
 
movie_height = 12;
movie_width = 310;

speed = Math.random()*4+2;
targx = Math.random()*(movie_width-_width);
targy = Math.random()*(movie_height-_height);
dist = _root.getdistance(_x, _y, targx, targy);

norm = speed/dist;
diffx = (targx-_x)*norm;
diffy = (targy-_y)*norm;
};


MovieClip.prototype.move = function () { 
var cycle;

cycle = 100;

if (_root.getdistance(_x, _y, targx, targy)>speed) {x += diffx;y += diffy;
} else {x = targx;
y = targy;
if (!this.t) {
t = getTimer();
}if (getTimer()-t>cycle) {reset();
t = 0;
}
}
_x = x;
_y = y;
}

then, for each symbol I use

         onClipEvent (enterFrame) {
            move();
         }

there has GOTTA be a quicker method.

[jdura99]

onClipEvent (load) { 
minX = 0; 
maxX = 550; 
minY = 0; 
maxY = 400; 
speed = 5; 
xDest = random(maxX - minX) + minX; 
yDest = random(maxY - minY) + minY;
} 

onClipEvent (enterFrame) { 
if (Math.round(_x) != xDest) { 
_x += xDif; 
xDif = (xDest - _x) / speed; 
} else { 
xDest = random(maxX - minX) + minX; 
} 
if (Math.round(_y) != yDest) { 
_y += yDif; 
yDif = (yDest - _y) / speed; 
} else { 
yDest = random(maxY - minY) + minY; 
} 
}

This might work?

Josh Dura

[RazoRmedia]

gerbick, what are you trying to do?

Your code above just moves the mc left and right a bit. What is your objective, what do you want it to do?

[gerbick]

yeah razor... that code is directly from my footer. I want to take a MC, or multiple versions thereof, and basically create TRUE random motion.

jdura... thanks for the code. but I gotta ask. how do I attach that to a MC?

yes, you can even treat me like an idiot on the answer

[RazoRmedia]

Originally posted by gerbick
jdura... thanks for the code. but I gotta ask. how do I attach that to a MC?

create a movieclip, right click on it and choose actions. then paste the text. Don't put it on a frame or it will generate errors.

[RazoRmedia]

heres a simpler albeit 'jerkier' version. Speed the frame rate up to 40 and watch it go.

onClipEvent (load) {
    min = "0";
    max = "200";
}
onClipEvent (enterFrame) {
    if (this._x <= min) {
        setProperty (this, _x, "100");
    }
    if (this._y <= min) {
        setProperty (this, _y, "100");
    }
    if (this._x >= max) {
        setProperty (this, _x, "100");
    }
    if (this._y >= min) {
        setProperty (this, _y, "100");
    }
    newx = random(20)-10;
    newy = random(20)-10;
    setProperty (this, _x, this._x + newx);
    setProperty (this, _y, this._y + newy);
}

[Ed Mack]

Okay, heres a stripped down version of some code I used ages ago to make "intellegant" movment. The use of trig isn't neccessary.

Adjust the random to give you the amount of rotation.

onClipEvent (load) {
	function Move (deg, speed) {
		var rad = deg*(Math.PI/180);
		var x = Math.cos(rad)*speed;
		var y = -Math.sin(rad)*speed;
		_y += y;
		_x += x;
	}
	speed = 2;
	angle = Math.random()*360;

	xb = 400;
	yb = 400;
}
onClipEvent (enterFrame) {
	angle +=( Math.random()*40)-20;
	Move(angle, speed);

	if(_x < 0 || _x > xb || _y < 0 || _y > yb){
		angle += 30;
	}
}

[theMatrix]

Originally posted by gerbick
and basically create TRUE random motion.

Sounds like what you want is Brownian motion -- a bounded random walk over a 2D lattice. A web search should turn up dozens of pages that will help you out. I used this same technique to animate a flickering flame in MAX using script controllers not too long ago.

have fun

too bad I don't speak ActionScript

[Ed Mack]

If you want brownian motion, change the random line in my script to this:

Change
angle +=( Math.random()*40)-20;

To
angle = Math.round(Math.random()*5)==5 ? Math.random()*360 : angle;

So it makes this:

onClipEvent (load) {
	function Move (deg, speed) {
		var rad = deg*(Math.PI/180);
		var x = Math.cos(rad)*speed;
		var y = -Math.sin(rad)*speed;
		_y += y;
		_x += x;
	}
	speed = 10;
	angle = Math.random()*360;

	xb = 400;
	yb = 400;
}
onClipEvent (enterFrame) {
	angle = Math.round(Math.random()*2)==2 ? angle + Math.random()*160 + 100 : angle;
	Move(angle, speed);

	if(_x < 0 || _x > xb || _y < 0 || _y > yb){
		angle += 30;
	}
}