CirclingPencil.py

from pygeo import *

v=display(scale=70)

p1 = FreePoint(-33.,-33,-3,color=WHITE)
p2 = FreePoint(-8,0,4,color=WHITE)
p3 = FreePoint(1,1,-11,color=WHITE)

plane=Plane(p1,p2,p3,color=WHITE)

p4 = Slider(plane,-14,16,41,color=WHITE)

lines=LineArray(plane,p4,color=BLUE)

p1a = Slider(plane,50,15,5,color=WHITE)
p2a = Slider(plane,-36,-18,5,color=WHITE)

line=Line(p1a,p2a,color=BLUE)

CirclingPencil(lines,line,color=RED,pointsize=1.5)
v.pickloop()