After Effects script to create a 3d cube

This script is used to create a 3d cube. You can later replace the different sides and spin the null around for easy animation. To make it more flexible, you can enter the size of the sides and the script will adjust.
In order for the sides to hold their positions (I've found that during animations, sometimes the sides will slip slightly out of place), they are all positioned with expressions and should keep their place no matter what you do to them.
There is a null object as well, all the sides have been parented to it and should make moving the cube around relatively simple.

//*********************************************************
//this is a script to make a 3d cube with a null object with which to control the cube
//to run, simply have an empty comp ready, select it in the project window,
//and run the script. the cube's sides are held in place through expressions
//so they will 'always' hold their positions.
//thanks to dan ebberts, nicholas white and everyone at creative cow for their help.



//****************************************************
// setting up project
side_size = prompt ("how big will each layer be?", "");
side_size = side_size/1
offset = side_size/2
myComp = app.project.item(1);
//***************************************************

//****************************
//create new 3d layers
for (i=1; i<=6; i++)
    {
      solid_name = i;
      mySolid = myComp.layers.addSolid([1.0,0.5,0.3], "side " +i , side_size, side_size, 1);
//make 3d
    mySolid.threeDLayer = true;
//add expression to fix the anchor point to the dead center of the solid
      solid_anchor_expression = "anchor = [" +offset+ "," +offset+ ",0]";
      mySolid.property("anchorPoint").expression = solid_anchor_expression;
//add expression to fix the x,y and z rotations to 0
        var rot_axis;
        for (r=1; r<=3; r++)
            {
            switch(r)
                  {
                  case 1:
                  rot_axis = 'X';
                  break;
                  case 2:
                  rot_axis = 'Y';
                  break;
                  case 3:
                  rot_axis = 'Z';
                  break;
                  default:
                  }
              rot_axis_expression = "rotation" +rot_axis+ " = 0";
              var rot_property = (rot_axis + " Rotation");
              mySolid.property(rot_property).expression = rot_axis_expression;
              }
//add expressions to orient the layers so they all face the right direction in 3d space
       var or_array;
        {
            switch(i)
                  {
                  case 1:
                  or_array = '[0,0,0]';
                  break;
                  case 2:
                  or_array = '[0,90,0]';
                  break;
                  case 3:
                  or_array = '[0,90,0]';
                  break;
                  case 4:
                  or_array = '[0,0,0]';
                  break;
                  case 5:
                  or_array = '[90,0,0]';
                  break;
                  case 6:
                  or_array = '[90,0,0]';
                  break;
                  default:
                  }
              or_array_expression = "orientation = " +or_array;
              mySolid.property("Orientation").expression = or_array_expression;
          }
//add expressions to position the layers correctly in 3d space
      var pos_array;
            {
            switch(i)
                  {
                  case 1:
                  pos_array = "[" +offset+ "," +offset+ ",0]";
                  break;
                  case 2:
                  pos_array = "[" +side_size+ "," +offset+ "," +offset+ "]";
                  break;
                  case 3:
                  pos_array = "[0," +offset+ "," +offset+ "]";
                  break;
                  case 4:
                  pos_array = "[" +offset+ "," +offset+ "," +side_size+ "]";
                  break;
                  case 5:
                  pos_array = "[" +offset+ ",0," +offset+ "]";
                  break;
                  case 6:
                  pos_array = "[" +offset+ "," +side_size+ "," +offset+ "]";
                  break;
                  default:
                  }
              pos_array_expression = "position = " +pos_array;
              mySolid.property("Position").expression = pos_array_expression;
            }
    }
//******************************************

//******************************************
//add null object, make it the parent of the solids
        
//add a null object with which to control the layers' movement
myNull = myComp.layers.addNull();
//make 3d
myNull.threeDLayer = true;
//add expression to fix the anchor point to the dead center of the null object
null_anchor_expression = "anchor = [0,0,0]";
myNull.property("anchorPoint").expression = null_anchor_expression;
//add expression to position the null in the dead center of the cube[/color]
myComp.layer(1).property("Position").setValue([offset,offset,offset]);//set the solids to be children of the null object
var null_parent;
null_parent = myComp.layer(1);
for (c=2; c<=7; c++)
    {
    myComp.layer(c).parent = null_parent;
    }
//***********************************************


alert ("done!");