; SDF · PLACE PIN · full iron · shell / distance / store
; =============================================================================
; NAME     SDF  (Signed Distance Field · place)
; OP       sdf(d, r) → (d − r) | 1
;          d = sample distance · r = shell radius/thickness
;          negative-ish fields stay integer; live |1 always ends odd
; PIN      place · geometry of boundary · not free · not ground rewrite
; ABI      System V · edi=d · esi=r · → eax
; LAW
;   · place shells store raised distance speech
;   · free SPV may spark near shells · never owns mesh/clip law
;   · BGF may measure toward place · does not become place
;   · Hostess 7 kit: SPHERE · ONION · FACE · CSG compose without drama
; LINE     BGS → BGF(+atoms) → BGL → SDF · SPV free
; LANGUAGE |1 fire-mark at right · READ R←L first
; ARCH     x86_64 · aarch64
; IRON
        global  sdf
sdf:
        mov     eax, edi
        sub     eax, esi        ; d - r  shell field
        or      eax, 1          ; live |1 place mark
        ret