npr op• 데이터 종류: image2d → image2d
• 호출: import fullseye as fs; fs.ledger.hatch_field(image, spacing_px=8.0, sigma=2.0, levels=3, cross_deg=90.0)(구현을 직접 호출하려면 import printpath; printpath.hatch_field(image, spacing_px=8.0, sigma=2.0, levels=3, cross_deg=90.0), 원장에서 가져오려면 opsprintpath.get("hatch_field"))
그림을 따라가는 크로스해칭 —— 방향은 구조 텐서에서。
> 아래 상세 설명은 원문입니다 —— 요약과 제목은 번역되어 있습니다.
The stroke direction is the local structure orientation (the existing
`structure_tensor_orientation`: strokes run *along* edges, not across them),
and the number of superposed hatch layers comes from the tone — one layer for
a light grey, up to *levels* for a dark one, each rotated by *cross_deg*.
★Why this earns its place: the direction is checkable against a picture
whose orientation is known by construction (a sine grating at 30° must give
strokes at 30°), and the tone is checkable by blurring the result. The usual
NPR routine offers neither.
Returns an `image2d`: 1 = paper, 0 = ink.
Raises `ValueError`: spacing below 2 px; levels below 1; non-positive
sigma; a non-finite or oversized image.
Limits: a single orientation per pixel, so crossings and junctions (where the
structure tensor is isotropic) get an arbitrary but locally smooth direction —
the coherence, not the orientation, is what says whether to trust it.
• 샘플 데이터 카탈로그(DL URL / 라이선스) —— 2-D 는 skimage.data(BSD/public)+ 합성, 3-D 는 실데이터 소스(Stanford/PDS 등)의 DL URL.
• 연산자의 내력·참고문헌 —— 이 연산자 족의 바탕이 된 연구/기법의 출처.
• 알고리즘의 정전(저자·연도)과 용도는 위의 패밀리 사용 가이드에 적혀 있습니다.
• poc_beats_fringes_and_screens — py -3.11 examples/poc_beats_fringes_and_screens.py
image2d 를 입력으로 받는 것)stipple_points_from_image · stipple_energy · stroke_tone_error · halftone_screen · engrave_lines · mosaic_tiles_sites · mosaic_tiles_render · print_layer_defect_map
npr)halftone_screen · halftone_moire_period · engrave_lines · mosaic_tiles_sites · mosaic_tiles_render
*Provenance: printpath.py — PRINTPATH 연산자 레지스트리. 이 op 노트는 tools/opdocs.py md 가 자동 생성합니다(직접 편집하지 마세요).*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.