球体の編み構造 | GhPython Tutorials

✅ Inputs

radius: float – 球の半径
amp: float – 縦方向（経線方向）の波の振幅
wave_cycles: int – 縦方向の波の繰り返し数（山と谷の数はこれの2倍）
res_theta: int – 経線方向の分割数
res_curve: int – 各曲線の解像度
pipe_radius: float – Pipeの太さ

✅ Outputs

results: list of Brep – 波打つ縦曲線と、それを横方向でつなぐ円に沿ったPipe構造

✅ Code

import Rhino.Geometry as rg
import math

# === 🔧 入力パラメータ例 ===
# radius = 100.0           # 球の半径
# amp = 2.0                # 波の振幅（縦方向）
# wave_cycles = 20         # 波の繰り返し数（経線方向）
# res_theta = 60           # 経線方向の分割数（縦）
# res_curve = 100          # 曲線分解能
# pipe_radius = 2.0        # Pipeの半径

# === 📐 基本設定
circumference = 2 * math.pi * radius
freq = wave_cycles * 2 * math.pi / circumference

# === 🧵 縦方向の波打つ曲線（経線方向）
vertical_curves = []
for i in range(res_theta):
    theta = (2 * math.pi) * i / res_theta
    phase = math.pi if i % 2 == 1 else 0.0
    points = []
    for j in range(res_curve + 1):
        t = float(j) / res_curve
        phi = math.pi * t
        arc_len = t * circumference
        r = radius + math.sin(arc_len * freq + phase) * amp
        x = r * math.sin(phi) * math.cos(theta)
        y = r * math.sin(phi) * math.sin(theta)
        z = r * math.cos(phi)
        points.append(rg.Point3d(x, y, z))
    curve = rg.Curve.CreateInterpolatedCurve(points, 3)
    vertical_curves.append(curve)

# === 🎯 緯線（波の山谷位置に円を配置）
num_peaks = int(wave_cycles * 2)
horizontal_curves = []
for k in range(num_peaks):
    t = (k + 0.5) / (num_peaks)
    phi = math.pi * t
    r = radius * math.sin(phi)
    z = radius * math.cos(phi)
    if abs(r) > 1e-6:
        circle = rg.Circle(rg.Plane(rg.Point3d(0, 0, z), rg.Vector3d.ZAxis), r)
        horizontal_curves.append(circle.ToNurbsCurve())

# === ✅ Pipe化
curves = vertical_curves + horizontal_curves
results = []
for c in curves:
    pipes = rg.Brep.CreatePipe(c, pipe_radius, False, rg.PipeCapMode.Round, True, 0.001, 0.001)
    if pipes:
        results.extend(pipes)