帕波斯(Pappus of Alexandria) 生于亚历山大,活跃于公元300—350前后.该螺线是一种绕在圆锥上的曲线.
#http://www.mathcurve.com/courbes3d/spiraleconic/pappus.shtml vertices = 12000 t = from (-20*PI) to (20*PI) r = 1 a = rand2(PI*0.2, PI*0.8) x = r*sin(a)*t*cos(t) z = r*sin(a)*t*sin(t) y = r*cot(a)*t
另一种写法:
vertices = 12000 t = from (-8*PI) to (8*PI) r = 10 a = rand2(PI*0.1, PI*0.9) x = r*t*sin(a)*cos(t) y = r*t*cos(a) z = r*t*sin(a)*sin(t)
数学图形(2.17)pappus螺线,布布扣,bubuko.com
原文：http://www.cnblogs.com/WhyEngine/p/3841009.html