ClippedFieldEvaluator

An IFieldEvaluator that reports the box-clipped field.

In the namespace construct::xport. Declared in src/libs/libconstruct/construct/export/BoxClip.hpp.

Detailed description

The post-process chain's `sdfProject` snaps mesh vertices onto the field's isosurface. Fed the RAW scene evaluator it drags the flat cut-face vertices back onto the model surface — re-expanding the clip that the extractor got right (measured: an exact cut at −1.0 grew to −0.62 after `sdfProject`). Wrapping the base evaluator so it reports `max(scene, box)` makes projection land on the clipped surface, so the flat face stays flat. Non-owning of the base; the base must outlive this wrapper (it does — both are locals in buildAndSaveMesh).