Ad esempio quete due prototype

//********MovieClip.prototype.VReveal **************
//
// Author : Broly
// Mail : davb86@supereva.it
// Version: FlashMX and MX2004 (player 6 or above)
//
// This prototype set a mask over a movieclip
// and show it using vertical bands.
// The bands are dinamically drawed,
// you can set width and the increment of height
//
// SYNTAX
// mcName.VReveal([w,h])
//
// PARAMETERS
// w - width of the band (if not set, assumed 10)
// l - increment of height for any pass (if not set, assumed 10)
//
// ***************** by Broly *********************


MovieClip.prototype.VReveal = function(w,h){
target = this._name
h_band = h ? h : 10
square_dim = w ? w : 10
a = 0
limit = mc._width / k
limitW = this._height
this.createEmptyMovieClip('mask',-1)
this.setMask(this.mask)
this.mask.createEmptyMovieClip('square'+a,0)
with(this.mask['square'+a]){
lineStyle(0,0x000000,0)
beginFill(0x000000,100)
lineTo(square_dim,0)
lineTo(square_dim,square_dim)
lineTo(0,square_dim)
lineTo(0,0)
_x = 0
_y = 0
}
this.mask.onEnterFrame = function(){
this['square'+a]._height += h_band
if(this['square'+a]._height >= limitW){
a++
this['square'+(a-1)].duplicateMovieClip('square'+a,a)
this['square'+a]._x = this['square'+(a-1)]._x+square_dim
this['square'+a]._height = this['square'+a]._width = square_dim
}
}
}

http://www.sephiroth.it/proto_detail.php?id=66

Oppure altri due esempi di Sephiroth :

http://www.sephiroth.it/file_detail.php?id=94

http://www.sephiroth.it/file_detail.php?id=95