/// <summary>
/// Configura la posicion de la cámara
/// </summary>
private void setCamera(Vector3 eye, Vector3 target, Vector3 up)
{
this.eye = eye;
zAxis = target - eye;
zAxis.Normalize();
viewDir = zAxis;
lookAt = eye + viewDir;
xAxis = Vector3.Cross(up, zAxis);
xAxis.Normalize();
yAxis = Vector3.Cross(zAxis, xAxis);
yAxis.Normalize();
//xAxis.Normalize();
viewMatrix = Matrix.Identity;
viewMatrix.M11 = xAxis.X;
viewMatrix.M21 = xAxis.Y;
viewMatrix.M31 = xAxis.Z;
viewMatrix.M41 = -Vector3.Dot(xAxis, eye);
viewMatrix.M12 = yAxis.X;
viewMatrix.M22 = yAxis.Y;
viewMatrix.M32 = yAxis.Z;
viewMatrix.M42 = -Vector3.Dot(yAxis, eye);
viewMatrix.M13 = zAxis.X;
viewMatrix.M23 = zAxis.Y;
viewMatrix.M33 = zAxis.Z;
viewMatrix.M43 = -Vector3.Dot(zAxis, eye);
// Extract the pitch angle from the view matrix.
accumPitchDegrees = Geometry.RadianToDegree((float)-Math.Asin((double)viewMatrix.M23));
Matrix worldMatrix = viewMatrix;
worldMatrix.Invert();
Matrix trans = Matrix.Translation(new Vector3(0f, -HeadPosition, 0f));
boundingBox.transform(worldMatrix * trans);
}