) {
          let x = i / numberOfRenderFrames;
          x = 2 * x - 1;
          data[i] = x;
        }

        return buffer;
      }

      // Generates a symmetric curve: Math.atan(5 * x) / (0.5 * Math.PI)
      // (with x == 0 corresponding to the center of the array)
      // This curve is arbitrary, but would be useful in the real-world.
      // To some extent, the actual curve we choose is not important in this
      // test, since the input vector walks through all possible curve values.
      f