In this work we demonstrate a simple kinematic model allowing for a variable amount of deformability for arbitrary shapes. A co-rotational finite element formulation is integrated over a shape submerged in a rough background mesh. The presented formulation allows to approximate the structural length-scale shock waves within a multi-body structure, which might be seen as a refinement of the solely rigid approach, for which such resolution is not readily available. For best illustration of core ideas, only simple one-body examples are given in the current paper. Nevertheless, the kinematic model has been employed within the Contact Dynamics time-stepping method and applied to large scale, parallel simulations of blocky structures with contact and friction. The source code is available at http://solfec.googlecode.com.