  An emerging theme across many domains of science and engineering is materials
that change shape, often dramatically. Determining their structure involves
solving a shape optimization problem where a given energy functional is
minimized with respect to the shape of the domain and auxiliary fields
describing the structure. Such problems are very challenging to solve and there
is a lack of suitable simulation tools that are both readily accessible and
general purpose. To address this gap, we present Morpho, an open-source
programmable environment, and demonstrate its versatility by showcasing three
applications to different areas of soft matter - swelling hydrogels, complex
fluids that form aspherical droplets, to soap films and membranes - and advise
on broader uses.
