Vollkornaffe

Bevy has been at 0.11 for the testbed since 780ba4a216aa9ef68d7f10db4a2b67b866699f43.

Pass particle data pointer

1

This is a possibility for passing through the `ParticleData` which contains the `log_vol_gain`. Something like this may be needed if we decide to control the correction more locally.

feat: Elastic energy

1

This adds functions to compute the elastic energy density function from a given deformation gradient. The new code is different from the existing one. See `pos_energy`: https://github.com/dimforge/sparkl/blob/43c13a65fef40b7872ec638c866c4b42926f3354/src/dynamics/models/elasticity_corotated_linear.rs#L35-L37 We may want...

``` panicked at 'called `Result::unwrap()` on an `Err` value: unexpected error: INVALID_FRAMEBUFFER_OPERATION' ```