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Problems with skeletal animation, chaotic movements

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Kind time of day. There was a problem with skeletal animation. I read out from mdl a file all data. At usual display of model all is normal, but as soon as I try to make skeletal animation of top of model move chaotically. I understand, what the question is enough not concrete, but I ask advice on the cores a mistake, for what reason such can occur?
public void display(GLAutoDrawable drawable)
  gl.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
  glu.gluLookAt(-70,75,350, 15,75,0, 0,1,0);
      object.CurFrame = object.MinFrame;

public void CalcAnimCoords(int frame)
        int CountOfCoords;
        int bNum;
        Bone b = new Bone();
        Vertex3D[] Coords;
        float x, y, z;
       for(int i=0; i<MeshLenght; i++)
           for (int j=0; j<mesh.vertex.length; j++)
               mesh.vertex[j].x = buf.vertex[j].x;
               mesh.vertex[j].y = buf.vertex[j].y;
               mesh.vertex[j].z = buf.vertex[j].z;
        for(int i=0; i<HelperLenght; i++)
            helper = InterpolationBone(frame, helper);
        for(int i=0; i<BoneLenght; i++)
            bone = InterpolationBone(frame, bone);
        for(int i=0; i<HelperLenght; i++)
            helper = CalculationBone(frame, helper);
        for(int i=0; i<BoneLenght; i++)
            bone = CalculationBone(frame, bone);
        for(int i=0; i<MeshLenght; i++) 
            Coords = new Vertex3D[10];
            for(int ii = 0; ii<mesh.VertexLenght; ii++)
               CountOfCoords = mesh.matrices[mesh.vertex_group[ii]].length;
                      for(int j = 0; j<CountOfCoords; j++)
                    bNum = mesh.matrices[mesh.vertex_group[ii]][j];
                          if ((HelperLenght>0) && (bone[bNum].object_id>=helper[0].object_id))
                        b = helper[bNum-helper[0].object_id];
                        b = bone[bNum];
                    Coords[j] = new Vertex3D();
                    Coords[j].x = mesh.vertex[ii].x - pivotpoint[b.object_id].x;
                    Coords[j].y = mesh.vertex[ii].y - pivotpoint[b.object_id].y;
                    Coords[j].z = mesh.vertex[ii].z - pivotpoint[b.object_id].z;

                    x = Coords[j].x * b.AbsMatrix.matrix[0][0]+
                    	Coords[j].y * b.AbsMatrix.matrix[1][0]+
                    	Coords[j].z * b.AbsMatrix.matrix[2][0];
                    y = Coords[j].x * b.AbsMatrix.matrix[0][1]+
                    	Coords[j].y * b.AbsMatrix.matrix[1][1]+
                    	Coords[j].z * b.AbsMatrix.matrix[2][1];
                    z = Coords[j].x * b.AbsMatrix.matrix[0][2]+
                    	Coords[j].y * b.AbsMatrix.matrix[1][2]+
                    	Coords[j].z * b.AbsMatrix.matrix[2][2];
                    Coords[j].x = x + b.AbsVector.x;
                    Coords[j].y = y + b.AbsVector.y;
                    Coords[j].z = z + b.AbsVector.z;
                mesh.vertex[ii].x = 0;
                mesh.vertex[ii].y = 0;
                mesh.vertex[ii].z = 0;
                for(int j=0; j< CountOfCoords; j++)
                    mesh.vertex[ii].x = mesh.vertex[ii].x + Coords[j].x;
                    mesh.vertex[ii].y = mesh.vertex[ii].y + Coords[j].y;
                    mesh.vertex[ii].z = mesh.vertex[ii].z + Coords[j].z;

                mesh.vertex[ii].x = mesh.vertex[ii].x/CountOfCoords;
                mesh.vertex[ii].y = mesh.vertex[ii].y/CountOfCoords;
                mesh.vertex[ii].z = mesh.vertex[ii].z/CountOfCoords;

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I understand, that the question is probably silly, but without your help to me to not understand. Tell, that I not so have asked or have made. The full code can is necessary lay out?

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* The method in which occurs definitions of the father and is caused a method for reception of an absolute matrix
* @param frame
* @param bone
* @return Entering bone with an absolute matrix
public Bone CalculationBone(int frame, Bone bone)
boolean IsHelper;

// If number "father" of the given bone is less than zero (-1) then the given bone does not have "father"
// and to consider an absolute matrix there is no sense
return bone;

// By default the father at a bone other bone
IsHelper = false;

// 1. Let's find the parent

// If we have "assistants" and at a bone "father" more or is equal to number of "assistant",
// then "father" for the given bone is "helper".
if(HelperLenght>0 && bone.parent_bone_id>=helper[0].object_id)
IsHelper = true;

bone = CalcAbsolute(frame, helper[bone.parent_bone_id-helper[0].object_id], bone);
bone = CalcAbsolute(frame, this.bone[bone.parent_bone_id], bone);

return bone;

public Bone CalcAbsolute(int frame, Bone Parent, Bone Child)
int j;
float x,y,z,sx,sy,sz;
Matrix m = new Matrix();
Quaternion q = new Quaternion();

Child.AbsMatrix = Matrix.mul(Parent.AbsMatrix,Child.AbsMatrix);

Child.AbsVector.x = Child.AbsVector.x - pivotpoint[Parent.object_id].x;
Child.AbsVector.y = Child.AbsVector.y - pivotpoint[Parent.object_id].y;
Child.AbsVector.z = Child.AbsVector.z - pivotpoint[Parent.object_id].z;

x = Parent.AbsVector.x +
Parent.AbsMatrix.matrix[0][0] * Child.AbsVector.x +
Parent.AbsMatrix.matrix[1][0] * Child.AbsVector.y +
Parent.AbsMatrix.matrix[2][0] * Child.AbsVector.z;
y = Parent.AbsVector.y +
Parent.AbsMatrix.matrix[0][1] * Child.AbsVector.x +
Parent.AbsMatrix.matrix[1][1] * Child.AbsVector.y +
Parent.AbsMatrix.matrix[2][1] * Child.AbsVector.z;
z = Parent.AbsVector.z +
Parent.AbsMatrix.matrix[0][2] * Child.AbsVector.x +
Parent.AbsMatrix.matrix[1][2] * Child.AbsVector.y +
Parent.AbsMatrix.matrix[2][2] * Child.AbsVector.z;

Child.AbsVector.x = x;
Child.AbsVector.y = y;
Child.AbsVector.z = z;

return Child;

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How are you handling things if Parent.AbsMatrix has not been calculated before you try calculating Child.AbsMatrix?

You need to make sure that the parent bones are done first.

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