FME Geometry, PythonCaller, GenerativeArt


#main_script
import fmeobjects
import numpy as np
from fmeobjects import FMELine, FMEPoint, FMEPolygon

"""
zig-zag triangular strip is one zigzag row:
upleft  right  downleft  right  ...
 /_\/_\
 vertices are spaced by L/2 horizontally.
    The vertical coordinate alternates between:
        baseline and baseline + H
            where H = sqrt(3)/2 * L (because we need f)
""" 

def triangle_row2(start, n, L, H):
    moves = np.array([
        (-L/2,  H),
        ( L,    0),
        (-L/2, -H),
        ( L,    0),
    ])
    steps = np.tile(moves, (n, 1))        # repeat cycle
    pts = np.vstack([start, start + np.cumsum(steps, axis=0)])
    return pts

def triangle_row(start, n, L):
    H = np.sqrt(3) / 2 * L
    x0, y0 = start
    pts = [
        (x0 + i * (L / 2), y0 + H * np.sin(i * np.pi / 2))
        for i in range(2 * n + 1)
        ]
    return np.array(pts)

class FeatureProcessor(object):
    def __init__(self):
        pass

    def input(self, feature: fmeobjects.FMEFeature):
        start_point = np.array([10,10])
        #trianguline = triangle_row(start_point, 10, 5)
        trianguline = triangle_row2(start_point, 11, 1, 3)
        pline_input = list(map(tuple, trianguline))
        line1 = FMELine(pline_input)
        feature.setGeometry(line1)
        self.pyoutput(feature)
        
        trianguline = triangle_row(start_point, 10, 1)
        pline_input = list(map(tuple, trianguline))
        line1 = FMELine(pline_input)
        feature.setGeometry(line1)
        self.pyoutput(feature)