code: public static Vector3f findClosestPointOnPlane(float aX, float aY, float aZ, float nX, float nY, float nZ, float pX, float pY, float pZ, Vector3f result) {
          float d = -(nX * aX + nY * aY + nZ * aZ);
          float t = nX * pX + nY * pY + nZ * pZ - d;
          result.x = pX - t * nX;
          result.y = pY - t * nY;
          result.z = pZ - t * nZ;
          return result;
      }
docs: Find the point on the given plane which is closest to the specified point <code>(pX, pY, pZ)</code> and store the result in <code>result</code>.
  
  @param aX
  the x coordinate of one point on the plane
  @param aY
  the y coordinate of one point on the plane
  @param aZ
  the z coordinate of one point on the plane
  @param nX
  the x coordinate of the unit normal of the plane
  @param nY
  the y coordinate of the unit normal of the plane
  @param nZ
  the z coordinate of the unit normal of the plane
  @param pX
  the x coordinate of the point
  @param pY
  the y coordinate of the point
  @param pZ
  the z coordinate of the point
  @param result
  will hold the result
  @return result