Hey Kirupa, Sticky Particles!

1

An interesting accident!

I was messing around with a pseudo-3d collision prototype, attempting to create a friction/inertia system, and I ended up with a kinda cool sitcky effect.

Sticky Particles

Click on the movie to regnerate the effect. It creates 10 particles in a z-index based 3d environment with random positioning and random motion vectors. The interesting thing is how my attempt at friction emulation created a stickiness. The particles almost seem to mimic atoms forming molecules!

I’m sure the code could be optimized, it is really just an accident! :slight_smile:

friction=0.005;
MovieClip.prototype.moveRandom=function(){
this.vx=0;
this.vy=0;
this.va=0;
while(this.vx==0){this.vx=Math.round((Math.random()*2-1)*((Math.random()*16)+16));}
while(this.vy==0){this.vy=Math.round((Math.random()*2-1)*((Math.random()*16)+16));}
while(this.va==0){this.va=Math.round((Math.random()*2-1)*((Math.random()*4)+4));}
this.onEnterFrame=function(){
this.swapDepths(this._xscale);
this.vx=this.vx<0?this.vx+_root.friction:this.vx-_root.friction;
this.vy=this.vy<0?this.vy+_root.friction:this.vy-_root.friction;
this.va=this.va<0?this.va+_root.friction:this.va-_root.friction;
this.vx=Math.abs(this.vx)>0.1?this.vx:0;
this.vy=Math.abs(this.vy)>0.1?this.vy:0;
this.va=Math.abs(this.va)>0.1?this.va:0;
thisone=this;
for(p=1;p<_root.particlecount;p++){
if(_root[p]!=thisone){
//if(thisone.hittest(_root[p]) && Math.abs(thisone._xscale-_root[p]._xscale)<20){
if(Math.pow(thisone._x-_root[p]._x,2)+Math.pow(thisone._y-_root[p]._y,2)+Math.pow(thisone._xscale-_root[p]._xscale,2)<=(thisone._xscale/100*1600)+(_root[p]._xscale/100*1600)){
_root[p].vx=thisone.vx=(_root[p].vx+thisone.vx)/2;
_root[p].vy=thisone.vy=(_root[p].vy+thisone.vy)/2;
_root[p].va=thisone.va=(_root[p].va+thisone.va)/2;
_root[p].vx*=-1;
_root[p]._x+=_root[p].vx;
_root[p].vy*=-1;
_root[p]._y+=_root[p].vy;
_root[p].va*=-1;
_root[p]._xscale+=_root[p].va;
_root[p]._yscale=_root[p]._xscale;
thisone.vx*=-1;
thisone._x+=_root[p].vx;
thisone.vy*=-1;
thisone._y+=_root[p].vy;
thisone.va*=-1;
thisone._xscale+=thisone.va;
thisone._yscale=thisone._xscale;
}
}
}
if(this._x+this.vx>Stage.width-this._width/2 || this._x+this.vx<this._width/2){
this.vx*=-1;
this._x+=this.vx;
}
if(this._y+this.vy>Stage.height-this._height/2 || this._y+this.vy<this._height/2){
this.vy*=-1;
this._y+=this.vy;
}
if(this._xscale>=100 || this._xscale<=10){
this.va*=-1;
this._xscale+=this.va;
this._yscale=this._xscale;
}
this._x+=this.vx;
this._y+=this.vy;
this._xscale+=this.va;
this._yscale+=this.va;
updateAfterEvent();
};
};
particlecount=10;
balls=['0xff0000','0xffff00','0x800080','0x800000','0x0000ff','0x000000','0x006400','0xe6e6e6','0xff0000','0xffff00'];
for(p=1;p<=particlecount;p++){
_root.createEmptyMovieClip(p,p);
with(_root[p]){
a=b=40;
colors =[ 0xffffff,0x0000ff ];
alphas =[ 100,100 ];
ratios =[ 0,255 ];
matrix ={matrixType:'box',x:-a/1.5,y:-b*1.5,w:a*2,h:b*2,r:(90/180)*Math.PI };
lineStyle(1,0x0000ff,0);
beginGradientFill('radial',colors,alphas,ratios,matrix );
j=a*0.70711;
n=b*0.70711;
i=j-(b-n)*a/b;
m=n-(a-j)*b/a;
moveTo(a,0);
curveTo(a,-m,j,-n);
curveTo(i,-b,0,-b);
curveTo(-i,-b,-j,-n);
curveTo(-a,-m,-a,0);
curveTo(-a,m,-j,n);
curveTo(-i,b,0,b);
curveTo(i,b,j,n);
curveTo(a,m,a,0);
endFill();
_x=Math.ceil(Math.random()*(Stage.width-_xscale)+_xscale/2);
_y=Math.ceil(Math.random()*(Stage.height-_yscale)+_yscale/2);
_xscale=_yscale=Math.ceil(Math.random()*90)+10;
}
_root[p].moveRandom();
}