Require help, Matrix and Billboards

Hi,

Matrixes are not my strong point and I need some help from someone who knows a lot more than me.

I have need of an Z,Y,X axis aligned billboards. I searched the code base and found spherical billboards. So I used that to get billboards. So anyway, I did some more searching and found the function forceFaceCameraZAxis, with a couple of modifications to remove the shape stuff and to rename it, I got ZAxis aligned billboards.

As I started with, matrixes are not my strong point. So I do not know what I need to modifiy to create YAxis and XAxis billbords.

Here is the function

void BillboardZAxis()
{
   MatrixF mat;
   dglGetModelview(&mat);
   Point3F z;
   mat.getColumn(2,&z);
   Point3F x,y;
   if (mFabs(z.y) < 0.99f)
   {
      // mCross(Point3F(0,1,0),tAxis,&x);
      x.set(z.z,0,-z.x);
      x.normalize();
      mCross(z,x,&y);
   }
   else
   {
      // mCross(z,Point3F(1,0,0),&y);
      y.set(0,z.z,-z.y);
      y.normalize();
      mCross(y,z,&x);
   }
   mat.setColumn(0,x);
   mat.setColumn(1,y);
   mat.setColumn(2,z);
   dglLoadMatrix(&mat);
}

Can someone help me create my BillboardYAxis and BillboardXAxis functions please?


Thanks

Edit: Oh another thing, how do I get billboards to rotate using my position, not the way I am facing?

If I am standing still and I rotate, the billboards will rotate as well. I don't want them to rotate until I move to a new position, and then they will rotate to face my position again. Am I making sence?