Function sdf_volume 

pub fn sdf_volume(v: SdfVolume, platform: Platform) -> SdfVolume

Normalize an authored volume for the runtime: clamp the raymarch knobs to sane bounds, force shadows off for translucent volumetrics (they write no depth), and collapse the per-backend fragment_shaders map to platform’s fragment_shader (the DirectX raymarch pass filters volumes by that path’s extension). The step-count bounds stay with the schema: they double as the runtime kernel’s loop bound.