code: protected void calculateDrawRectF() {
          mFillCircleRectF = getArcRect(mClockwiseReachedArcWidth);
          mReachedArcRectF = getArcRect(mClockwiseReachedArcWidth / 2);
          mOutlineArcRectF = getArcRect(mClockwiseOutlineArcWidth / 2);
      }
docs: Calculates the coordinates of {@link #mOutlineArcRectF} and
  {@link #mReachedArcRectF}