Function mass_measures_handle_native 

pub fn mass_measures_handle_native(
    handle: u32,
) -> Result<MassProperties, String>

Surface area and volume of a resident solid — the native sibling of mass_properties_handle_native for a caller that reads NOTHING but those two numbers (examples/case_replay.rs records volume and area per solid and discards the rest). The full entry runs a second station sweep over every trimmed face for the nine moment integrands, which costs as much again as the area/volume sweep: on anotherBooleanFail’s imported 32-face body 2.6 s against 1.3 s, and 5.3 s of that case’s 12.9 s replay went to moments nobody read. The two numbers come out of the same solid_mass_properties call the full entry starts with, so they are bit-identical to its volume and surface_area; the full entry’s refusal of a non-positive volume is kept so a caller switching over sees the same Err on the same solids. Reads the solid in one registry borrow.