3D bubbles | Reversible knitting stitch is not hard to do.

3D bubbles | Reversible knitting stitch
Knit 4 below: Drop stitch off needle and unravel 4 rows down, insert needle in stitch in the 5th row down and under the 4 loose strands, and knit, catching the 4 loose strands behind stitch
Knitted a multiple of 4 sts, +1 and a 12-row repeat.
Row 1 - wrong side: Purl.
Row 2 - right side:  Knit
Row 3: Purl.
Row 4: Knit.
Row 5: Purl.
Row 6: * Knit 3, knit 4 below; repeat from * to last st, knit 1.
Row 7: Purl.
Row 8: Knit.
Row 9: Purl.
Row 10: Knit.
Row 11: Purl.
Row 12: Knit1, * knit 4 below, knit3; repeat from * to end.

This pattern can be adapted to circular knitting by knit all the odd numbered rows.