code: protected float[] findLimitsOneLine() {
          float x1 = findLimitsPoint(leftWall);
          if (lineStatus == LINE_STATUS_OFFLIMITS || lineStatus == LINE_STATUS_NOLINE)
              return null;
          float x2 = findLimitsPoint(rightWall);
          if (lineStatus == LINE_STATUS_NOLINE)
              return null;
          return new float[]{x1, x2};
      }
docs: Finds the intersection between the <CODE>yLine</CODE> and the two
  column bounds. It will set the <CODE>lineStatus</CODE> appropriately.
  
  @return a <CODE>float[2]</CODE>with the x coordinates of the intersection