def generate_path_tree(self):
""" Specialized path generation for Waterbomb tesselation pattern
"""
unit_factor = self.calc_unit_factor()
length = self.options.length * unit_factor
vertex_radius = self.options.vertex_radius * unit_factor
cols = self.options.columns
lines = self.options.lines
phase_shift = self.options.phase_shift
pattern_first_line = self.options.pattern_first_line
pattern_last_line = self.options.pattern_last_line
# create vertices
vertex_line_types = [[
Path(((i / 2.) * length, 0), style='p', radius=vertex_radius)
for i in range(2 * cols + 1)
],
[
Path((i * length, 0),
style='p',
radius=vertex_radius)
for i in range(cols + 1)
],
[
Path(((i + 0.5) * length, 0),
style='p',
radius=vertex_radius)
for i in range(cols)
]]
vertices = []
for i in range(2 * lines + 1):
if i % 2 == 0 or (pattern_first_line == 'magic_ball'
and i == 1) or (pattern_last_line == 'magic_ball'
and i == 2 * lines - 1):
type = 0
elif (i / 2 + phase_shift) % 2 == 0:
type = 1
else:
type = 2
vertices = vertices + Path.list_add(vertex_line_types[type],
(0, 0.5 * i * length))
# create a list for the horizontal creases and another for the vertical creases
# alternate strokes to minimize laser cutter path
corr_fist_line = length / 2 if pattern_first_line == 'magic_ball' else 0
corr_last_line = length / 2 if pattern_last_line == 'magic_ball' else 0
grid = [
Path.generate_hgrid([0, length * cols], [0, length * lines], lines,
'm'),
Path.generate_vgrid(
[0, length * cols],
[corr_fist_line, length * lines - corr_last_line], 2 * cols,
'm')
]
vgrid_a = Path.generate_vgrid([0, length * cols], [0, length / 2],
2 * cols, 'v')
vgrid_b = Path.list_add(vgrid_a, (0, (lines - 0.5) * length))
if pattern_first_line == 'magic_ball' and pattern_last_line == 'magic_ball':
grid[1] = [[vgrid_a[i], grid[1][i], vgrid_b[i]] if i %
2 == 0 else [vgrid_b[i], grid[1][i], vgrid_a[i]]
for i in range(len(grid[1]))]
elif pattern_first_line == 'magic_ball':
grid[1] = [[vgrid_a[i], grid[1][i]] if i %
2 == 0 else [grid[1][i], vgrid_a[i]]
for i in range(len(grid[1]))]
elif pattern_last_line == 'magic_ball':
grid[1] = [[grid[1][i], vgrid_b[i]] if i %
2 == 0 else [vgrid_b[i], grid[1][i]]
for i in range(len(grid[1]))]
# create generic valley Path lines, one pointing up and other pointing down
valley_types = [
Path([(i * length / 2, (1 - i % 2) * length / 2)
for i in range(2 * cols + 1)], 'v'),
Path([(i * length / 2, (i % 2) * length / 2)
for i in range(2 * cols + 1)], 'v')
]
# define which lines must be of which type, according to parity and options
senses = np.array(
[bool((i % 2 + i) / 2 % 2) for i in range(2 * lines)])
senses = 1 * senses # converts bool array to 0's and 1's
if phase_shift:
senses = np.invert(senses)
if pattern_first_line == "magic_ball":
senses[0] = ~senses[0]
if pattern_last_line == "magic_ball":
senses[-1] = ~senses[-1]
valleys = [
valley_types[senses[i]] + (0, i * length / 2)
for i in range(2 * lines)
]
# convert first and last lines to mountains if magic_ball
if pattern_first_line == "magic_ball":
valleys[0].style = 'm'
if pattern_last_line == "magic_ball":
valleys[-1].style = 'm'
# invert every two lines to minimize laser cutter movements
for i in range(1, 2 * lines, 2):
valleys[i].invert()
self.edge_points = [
(0 * length * cols, 0 * length * lines), # top left
(1 * length * cols, 0 * length * lines), # top right
(1 * length * cols, 1 * length * lines), # bottom right
(0 * length * cols, 1 * length * lines)
] # bottom left
self.path_tree = [grid, valleys, vertices]
