Working with IK Armatures in AS3

programming flash
1

Hi everyone. I’m atm trying to get a little proof of concept up and running for armature control. I’ve gotten an armature of a top-down human figure setup, to point its arms at something. This worked perfectly initially.

Now I’m trying to get it to point it’s arms at a point, arms length away, in the direction of the cursor. so that the arms come together at the end.

I made a movieclip for this purpose and put my armature inside it. However I’m having problems accessing the position of the movieclip:

My code can be found at the bottom of the post. The important line is:

var pos:MovieClip = tree.parent;

This throws the following compile error:

Scene 1, Layer 'actions', Frame 1, Line 47    1119: Access of possibly undefined property parent through a reference with static type fl.ik:IKArmature.

As far as I can tell, this basically means you can’t get the parent of an armature. Could that really be so? Seems pointlessly inflexible. If the parent were null then that would indicate a problem with assigning it properly, but it won’t even let me check that property at all, which I think means that it doesn’t exist.

For reference, I’ve never used addChild anywhere in the code, as my movieclip containing the armature is present on stage to begin with. I don’t generally do that but it;s supposed to just be a quick test.

Farther to the above, I’m attempting testing the opposite way.
I instantiated the movieclip as a class onstage, and tried using getChildAt to find the armature within it.

This failed horribly, and after running through a loop of it’s children, I found out that the 5 child objects under it were all the seperate movieclips that the armature connects. It seems I can’t access the armature itself through the parent/child system.

I’m thoroughly confused about how this all works. any advice?


import fl.ik.* 
import flash.geom.Point;
import flash.display.MovieClip;
 
//var tree:IKArmature = IKManager.getArmatureByName("figure");
var tree:IKArmature;
var ik1:IKMover;
var ik2:IKMover;
var armlength:int = 100;

function set_params()
{
    if (tree != null)
    {
        trace('tree');
        IKManager.setStage(stage);
        var bone1:IKBone = tree.getBoneByName("arm1bone"); 
        var bone2:IKBone = tree.getBoneByName("arm2bone"); 
        var endEffector1:IKJoint = bone1.tailJoint; 
        var endEffector2:IKJoint = bone2.tailJoint; 
        var pos1:Point = endEffector1.position; 
        var pos2:Point = endEffector2.position; 
        
        ik1 = new IKMover(endEffector1, pos1); 
        ik1.limitByDistance = true; 
        ik1.distanceLimit = 0.1; 
        ik1.limitByIteration = true; 
        ik1.iterationLimit = 10; 
        
        ik2 = new IKMover(endEffector2, pos2); 
        ik2.limitByDistance = true; 
        ik2.distanceLimit = 0.1; 
        ik2.limitByIteration = true; 
        ik2.iterationLimit = 10; 
    }
}
 
stage.addEventListener(Event.ENTER_FRAME, frameFunc); 
 
function frameFunc(event:Event) 
{ 
        tree = IKManager.getArmatureAt(0);
        trace(tree);
        set_params();
        if (tree != null)
        {
            var pos:MovieClip = tree.parent;
            var pt = new Point(mouseX, mouseY); 
            var me = new Point(pos.x, pos.y);
            //var me = new Point(tree.parent.x, tree.parent.y);
            var direction = new Point(pt.x - me.x, pt.y - me.y);
            direction = direction.normalize(1);
            direction.x = direction.x * armlength;
            direction.y = direction.y * armlength;
            pt  = me.add(direction);
            ik1.moveTo(pt); 
            ik2.moveTo(pt); 
        }
}