| 42 | # Koch curve, after Helge von Koch who introduced this geometric figure in 1904 |
| 43 | # p. 146 |
| 44 | def fractalgon(self, n, rad, lev, dir): |
| 45 | import math |
| 46 | |
| 47 | # if dir = 1 turn outward |
| 48 | # if dir = -1 turn inward |
| 49 | edge = 2 * rad * math.sin(math.pi / n) |
| 50 | self.pu() |
| 51 | self.fd(rad) |
| 52 | self.pd() |
| 53 | self.rt(180 - (90 * (n - 2) / n)) |
| 54 | for i in range(n): |
| 55 | self.fractal(edge, lev, dir) |
| 56 | self.rt(360 / n) |
| 57 | self.lt(180 - (90 * (n - 2) / n)) |
| 58 | self.pu() |
| 59 | self.bk(rad) |
| 60 | self.pd() |
| 61 | |
| 62 | # p. 146 |
| 63 | def fractal(self, dist, depth, dir): |