surface op• 資料種類:無 → mesh(僅由參數決定的運算子 —— 不接受影像或資料輸入)
• 呼叫: import fullseye as fs; fs.ledger.gyroid_isosurface(shape=(64, 64, 64), level=0.0, periods=1.0)(要直接呼叫實作,import render3d; render3d.gyroid_isosurface(shape=(64, 64, 64), level=0.0, periods=1.0);從台帳取用則 ops3d.get("gyroid_isosurface"))
螺旋二十四面體(gyroid)—— 由節面近似生成的三重週期曲面。
> 以下的詳細說明為原文 —— 摘要與標題已翻譯。
Samples sin x cos y + sin y cos z + sin z cos x over periods unit cells and extracts the level set. At level = 0 the field is odd under the body-centred inversion, so the two sides have exactly equal volume — a symmetry fact, independent of the meshing, that the existing mesh_volume can be pointed at.
★Honest limit, stated in the contract: this is the *nodal approximation* to the gyroid, not the exact triply periodic minimal surface. Schoen's gyroid has H = 0 everywhere; the nodal surface has a residual mean curvature (measured, not hidden) of about 12 % of the principal-curvature scale at a 64³ grid —— compare the exact families in minimal_surface, whose |H| median is 1e-4 against a curvature scale of order 1. Use the gyroid as a scaffold and a picture, not as a claim of minimality.
shape : (nz, ny, nx)
level : float
Iso value. 0 gives the balanced surface; non-zero splits the volume.
periods : float
Unit cells along each axis.
Returns a mesh (vertices, faces).
★The thickened solid form lives in gyroid_solid_mask, not behind a keyword here —— one function that returns a mesh or a volume depending on an argument cannot be given a single declared output type, and a ledger row that lies about its output is the defect class this library keeps catching (indices_to_labels: one word covering a 1-D mask and a 3-D volume).
Raises ValueError: a grid below 8 per axis or over the cap; non-positive periods; a level outside the field's range (no surface exists there — reported rather than returning an empty mesh); negative thickness.
• 範例資料目錄(下載 URL / 授權) —— 2-D 用 skimage.data(BSD/公有領域)加合成圖,3-D 給出真實資料源(Stanford/PDS 等)的下載 URL。
• 運算子來歷與參考文獻 —— 該運算子族所依據的研究/方法出處。
• minimal_surfaces — py -3.11 examples_3d/minimal_surfaces.py
mesh 作為輸入)mesh_to_voxel · mesh_to_points · to_points · fuse_to_voxel · ambient_occlusion · cast_shadow · supersample_mesh · render_beauty
surface)minimal_surface · minimal_surface_bend · gyroid_solid_mask · curve3d_tube_mesh
*Provenance: render3d.py — 3D 運算子登記表。本條目由 tools/opdocs.py md 自動產生(請勿手動編輯)。*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.