我们可以直接用Flash的ASAS代码生成风吹云飘，风吹着青草左右摇摆的动画。因为AS的运算会拖慢机器，所以这里就不提供效果演示了，给大家截个图。
制作方法如下。 首先建立两个空的影片剪辑cloud和grass。 先建立云的影片剪辑（里面什么都不画） 选择该元件的第一帧，添加如下代码。 同样办法再新建立一个草的影片剪辑
//Number of clouds
clouds=6;
//These are just general boundaries.
//To use exact boundaries, create a mask in the parent level of the size desired
//Height of the sky
skyheight=Stage.height;
//Width of the sky
skywidth=Stage.width;
//Max size of a cloud
cloudsize=300;
//Amount of blur applied to the shapes to make them cloud-like
blursize=40;
//Clouds move at a random speed. this is the minimum speed
cloudminspeed=.5;
//Variance in speed from cloud to cloud
cloudspeedvariance=1;
//Create the clouds
for(c=1;c<=clouds;c++){
//create an empty movie clip to hold the cloud
this.createEmptyMovieClip("cloud"+c,this.getNextHighestDepth());
//generate a cloud. Pass in the instance name of the newly created cloud
shapecloud("cloud"+c);
//Set the x position to a random position within the boundaries
eval("cloud"+c)._x=Math.random()*skywidth-eval("cloud"+c)._x/2;
//Set the y position to a random position within the boundaries
eval("cloud"+c)._y=Math.random()*(skyheight)-eval("cloud"+c)._height;
}
//Run at the start of each frame
onEnterFrame=function(){
//Run for each cloud
for(c=1;c<=clouds;c++){
//Move the cloud to the left according to its speed
eval("cloud"+c)._x-=eval("cloud"+c).cloudspeed;
//If the cloud is past the stage to the left, reset it to the right. Create a new shape and color
if(eval("cloud"+c)._x+(eval("cloud"+c)._width/2)+cloudsize<0){
//Reset the x position
eval("cloud"+c)._x=skywidth;
//Reshape and recolor the cloud
shapecloud("cloud"+c);
}
}
}
//This function creates the shape and color of a cloud
function shapecloud(cloudid){
//Clear the current contents of the cloud
eval(cloudid).clear();
//Set the new shade between 224 and 255. This number is used for the red, green, and blue, to create a grayscale color
cloudcolor=Math.round(Math.random()*31)+224;
//Use no line
eval(cloudid).lineStyle(undefined, (cloudcolor+cloudcolor*0x100+cloudcolor*0x10000), 100, false, "none", "none", "none", 1);
//Set the fill color. cloudcolor is used 3 times, for red, green, and blue
eval(cloudid).beginFill((cloudcolor+cloudcolor*0x100+cloudcolor*0x10000));
//Set a starting coordinate for the cloud
eval(cloudid).moveTo(Math.random()*cloudsize,Math.random()*cloudsize);
//Draw an invisible line to another point the combined lines form shapes, which are the clouds.
//They don't look much like clouds until the blur is applied
eval(cloudid).lineTo(Math.random()*cloudsize,Math.random()*cloudsize);
eval(cloudid).lineTo(Math.random()*cloudsize,Math.random()*cloudsize);
eval(cloudid).lineTo(Math.random()*cloudsize,Math.random()*cloudsize);
eval(cloudid).lineTo(Math.random()*cloudsize,Math.random()*cloudsize);
eval(cloudid).lineTo(Math.random()*cloudsize,Math.random()*cloudsize);
//Apply a blur to the shape
eval(cloudid).filters = [new flash.filters.BlurFilter(blursize,blursize,2)];
//Set a new cloud speed
eval(cloudid).cloudspeed=Math.random()*cloudspeedvariance+cloudminspeed;
}
