Customizable sunglasses case

This is a parametric case made of two snap-fit halves, intended to protect your sunglasses, for example when stored in a backpack.

### Customization

The overall shape is made of curved surfaces that should closely match the (convex hull of) your sunglasses, for minimum space requirement. It has two planes of symmetry, so the sunglasses can be inserted without paying attention to orientation.

The shape is determined from two 2d profiles:
- Top view : the intersection of an ellipse and a circle
- Side view : the intersection of three circles (two of them symmetric) and a half-plan, with rounded corners

The top and side views will be the corresponding projections of the resulting 3d shape, but this is not just an intersection of those. It's more "rounded" than the intersection.

You can use the Thingiverse or OpenScad Customizer to tune the parameters and view the 2d profiles and the 3d shape (the latter is faster and more convenient). Each 2d profile should contain the corresponding