When one of the layers embeds complex shapes , such as sequences of symbols forming a text , and another layer contains parallel lines or curves , the superimposition image may gives rise to magnified shapes , called shape moirÃ patterns . When one of the layers embeds complex shapes , such as sequences of symbols forming a text , and another layer contains parallel lines or curves , the superimposition image may give rise to magnified shapes , called shape moirÃ patterns .