A-Star v2.0

var current_x=0;
var current_y=0;
var final_x=4;
var final_y=4;
var grid_size=5;

var walkable_array=[
[0,0,0,0,0],
[1,1,1,1,0],
[0,0,0,0,0],
[0,0,0,0,0],
[0,0,0,0,0]
];

for(var k=0;k<grid_size;k++){
if(walkable_array[k]==undefined){
walkable_array[k]=[];
}
}
for(k=0;k<grid_size;k++){
for(var l=0;l<grid_size;l++){
if(walkable_array[k][l]==undefined){
walkable_array[k][l]=[];
}
}
}

for(var i=0;i<grid_size;i++){
for(var j=0;j<grid_size;j++){
var square_var:MovieClip=new MovieClip();
stage.addChild(square_var);
square_var.graphics.lineStyle(1,0x000000);
square_var.graphics.drawRect(0,0,50,50);
square_var.x=j*square_var.width;
square_var.y=i*square_var.height;
square_var.name=j+"_"+i;
}
}

stage.addEventListener(MouseEvent.MOUSE_DOWN,md);
function md(e:*){
astar(current_x,current_y,final_x,final_y);
}

var astar_obj={};
var astar_arr=[];
var used_data={};
var current_object;
var object_number=0;

function astar(current_x,current_y,final_x,final_y){
num=0;
delete used_data[object_number];
delete astar_obj[object_number];
astar_arr=[];
object_number++;
astar_obj[object_number]={};
used_data[object_number]={};
astar_arr[astar_arr.length]=astar_obj[object_number][current_x+"_"+current_y]={x:current_x,y:current_y,prev_x:current_x,prev_y:current_y};
for(var i=0;i<astar_arr.length;i++){
var current_object=astar_arr[i];
searchProcess(current_object,current_object.x+1,current_object.y);
searchProcess(current_object,current_object.x,current_object.y+1);
searchProcess(current_object,current_object.x-1,current_object.y);
searchProcess(current_object,current_object.x,current_object.y-1);
}
}
var num=0;
var distance_limit=100;
function searchProcess(a,b,c){
num++;
if(b>-1&&c>-1&&used_data[object_number][b+"_"+c]==undefined){
used_data[object_number][b+"_"+c]=false;
num--;
num++;
}

if(b>-1&&c>-1&&b<grid_size&&c<grid_size&&walkable_array[b][c]==0&&used_data[object_number][b+"_"+c]==false&&distanceChecker(b,current_x)<=distance_limit &&distanceChecker(c,current_y)<=distance_limit){
used_data[object_number][b+"_"+c]=true;
astar_arr[astar_arr.length]=astar_obj[object_number][(b)+"_"+(c)]={x:b,y:c,prev_x:a.x,prev_y:a.y};
num--;
num++;
if(final_x==b&&final_y==c){
num--;
var temp_x=b;
var temp_y=c;
var astar_direction=[];
while(temp_x!=current_x||temp_y!=current_y){
num++;
var temp_x_2=astar_obj[object_number][(temp_x)+"_"+(temp_y)].prev_x;
var temp_y_2=astar_obj[object_number][(temp_x)+"_"+(temp_y)].prev_y;
temp_x=temp_x_2;
temp_y=temp_y_2;
astar_direction.push(astar_obj[object_number][(temp_x)+"_"+(temp_y)].x);
astar_direction.push(astar_obj[object_number][(temp_x)+"_"+(temp_y)].y);
}
trace(astar_direction);
}
}
}

function distanceChecker(a,b){
if(a>b){
return a-b;
}else{
return b-a;
}
}