215 lines
6.8 KiB
Python
215 lines
6.8 KiB
Python
|
"""
|
||
|
|
Contains a classes for generating hatch patterns.
|
||
|
|
"""
|
||
|
|
|
||
|
|
import numpy as np
|
||
|
|
from matplotlib.path import Path
|
||
|
|
|
||
|
|
|
||
|
|
class HatchPatternBase:
|
||
|
|
"""
|
||
|
|
The base class for a hatch pattern.
|
||
|
|
"""
|
||
|
|
pass
|
||
|
|
|
||
|
|
|
||
|
|
class HorizontalHatch(HatchPatternBase):
|
||
|
|
def __init__(self, hatch, density):
|
||
|
|
self.num_lines = int((hatch.count('-') + hatch.count('+')) * density)
|
||
|
|
self.num_vertices = self.num_lines * 2
|
||
|
|
|
||
|
|
def set_vertices_and_codes(self, vertices, codes):
|
||
|
|
steps, stepsize = np.linspace(0.0, 1.0, self.num_lines, False,
|
||
|
|
retstep=True)
|
||
|
|
steps += stepsize / 2.
|
||
|
|
vertices[0::2, 0] = 0.0
|
||
|
|
vertices[0::2, 1] = steps
|
||
|
|
vertices[1::2, 0] = 1.0
|
||
|
|
vertices[1::2, 1] = steps
|
||
|
|
codes[0::2] = Path.MOVETO
|
||
|
|
codes[1::2] = Path.LINETO
|
||
|
|
|
||
|
|
|
||
|
|
class VerticalHatch(HatchPatternBase):
|
||
|
|
def __init__(self, hatch, density):
|
||
|
|
self.num_lines = int((hatch.count('|') + hatch.count('+')) * density)
|
||
|
|
self.num_vertices = self.num_lines * 2
|
||
|
|
|
||
|
|
def set_vertices_and_codes(self, vertices, codes):
|
||
|
|
steps, stepsize = np.linspace(0.0, 1.0, self.num_lines, False,
|
||
|
|
retstep=True)
|
||
|
|
steps += stepsize / 2.
|
||
|
|
vertices[0::2, 0] = steps
|
||
|
|
vertices[0::2, 1] = 0.0
|
||
|
|
vertices[1::2, 0] = steps
|
||
|
|
vertices[1::2, 1] = 1.0
|
||
|
|
codes[0::2] = Path.MOVETO
|
||
|
|
codes[1::2] = Path.LINETO
|
||
|
|
|
||
|
|
|
||
|
|
class NorthEastHatch(HatchPatternBase):
|
||
|
|
def __init__(self, hatch, density):
|
||
|
|
self.num_lines = int((hatch.count('/') + hatch.count('x') +
|
||
|
|
hatch.count('X')) * density)
|
||
|
|
if self.num_lines:
|
||
|
|
self.num_vertices = (self.num_lines + 1) * 2
|
||
|
|
else:
|
||
|
|
self.num_vertices = 0
|
||
|
|
|
||
|
|
def set_vertices_and_codes(self, vertices, codes):
|
||
|
|
steps = np.linspace(-0.5, 0.5, self.num_lines + 1)
|
||
|
|
vertices[0::2, 0] = 0.0 + steps
|
||
|
|
vertices[0::2, 1] = 0.0 - steps
|
||
|
|
vertices[1::2, 0] = 1.0 + steps
|
||
|
|
vertices[1::2, 1] = 1.0 - steps
|
||
|
|
codes[0::2] = Path.MOVETO
|
||
|
|
codes[1::2] = Path.LINETO
|
||
|
|
|
||
|
|
|
||
|
|
class SouthEastHatch(HatchPatternBase):
|
||
|
|
def __init__(self, hatch, density):
|
||
|
|
self.num_lines = int((hatch.count('\\') + hatch.count('x') +
|
||
|
|
hatch.count('X')) * density)
|
||
|
|
self.num_vertices = (self.num_lines + 1) * 2
|
||
|
|
if self.num_lines:
|
||
|
|
self.num_vertices = (self.num_lines + 1) * 2
|
||
|
|
else:
|
||
|
|
self.num_vertices = 0
|
||
|
|
|
||
|
|
def set_vertices_and_codes(self, vertices, codes):
|
||
|
|
steps = np.linspace(-0.5, 0.5, self.num_lines + 1)
|
||
|
|
vertices[0::2, 0] = 0.0 + steps
|
||
|
|
vertices[0::2, 1] = 1.0 + steps
|
||
|
|
vertices[1::2, 0] = 1.0 + steps
|
||
|
|
vertices[1::2, 1] = 0.0 + steps
|
||
|
|
codes[0::2] = Path.MOVETO
|
||
|
|
codes[1::2] = Path.LINETO
|
||
|
|
|
||
|
|
|
||
|
|
class Shapes(HatchPatternBase):
|
||
|
|
filled = False
|
||
|
|
|
||
|
|
def __init__(self, hatch, density):
|
||
|
|
if self.num_rows == 0:
|
||
|
|
self.num_shapes = 0
|
||
|
|
self.num_vertices = 0
|
||
|
|
else:
|
||
|
|
self.num_shapes = ((self.num_rows // 2 + 1) * (self.num_rows + 1) +
|
||
|
|
(self.num_rows // 2) * (self.num_rows))
|
||
|
|
self.num_vertices = (self.num_shapes *
|
||
|
|
len(self.shape_vertices) *
|
||
|
|
(1 if self.filled else 2))
|
||
|
|
|
||
|
|
def set_vertices_and_codes(self, vertices, codes):
|
||
|
|
offset = 1.0 / self.num_rows
|
||
|
|
shape_vertices = self.shape_vertices * offset * self.size
|
||
|
|
if not self.filled:
|
||
|
|
inner_vertices = shape_vertices[::-1] * 0.9
|
||
|
|
shape_codes = self.shape_codes
|
||
|
|
shape_size = len(shape_vertices)
|
||
|
|
|
||
|
|
cursor = 0
|
||
|
|
for row in range(self.num_rows + 1):
|
||
|
|
if row % 2 == 0:
|
||
|
|
cols = np.linspace(0, 1, self.num_rows + 1)
|
||
|
|
else:
|
||
|
|
cols = np.linspace(offset / 2, 1 - offset / 2, self.num_rows)
|
||
|
|
row_pos = row * offset
|
||
|
|
for col_pos in cols:
|
||
|
|
vertices[cursor:cursor + shape_size] = (shape_vertices +
|
||
|
|
(col_pos, row_pos))
|
||
|
|
codes[cursor:cursor + shape_size] = shape_codes
|
||
|
|
cursor += shape_size
|
||
|
|
if not self.filled:
|
||
|
|
vertices[cursor:cursor + shape_size] = (inner_vertices +
|
||
|
|
(col_pos, row_pos))
|
||
|
|
codes[cursor:cursor + shape_size] = shape_codes
|
||
|
|
cursor += shape_size
|
||
|
|
|
||
|
|
|
||
|
|
class Circles(Shapes):
|
||
|
|
def __init__(self, hatch, density):
|
||
|
|
path = Path.unit_circle()
|
||
|
|
self.shape_vertices = path.vertices
|
||
|
|
self.shape_codes = path.codes
|
||
|
|
Shapes.__init__(self, hatch, density)
|
||
|
|
|
||
|
|
|
||
|
|
class SmallCircles(Circles):
|
||
|
|
size = 0.2
|
||
|
|
|
||
|
|
def __init__(self, hatch, density):
|
||
|
|
self.num_rows = (hatch.count('o')) * density
|
||
|
|
Circles.__init__(self, hatch, density)
|
||
|
|
|
||
|
|
|
||
|
|
class LargeCircles(Circles):
|
||
|
|
size = 0.35
|
||
|
|
|
||
|
|
def __init__(self, hatch, density):
|
||
|
|
self.num_rows = (hatch.count('O')) * density
|
||
|
|
Circles.__init__(self, hatch, density)
|
||
|
|
|
||
|
|
|
||
|
|
class SmallFilledCircles(SmallCircles):
|
||
|
|
size = 0.1
|
||
|
|
filled = True
|
||
|
|
|
||
|
|
def __init__(self, hatch, density):
|
||
|
|
self.num_rows = (hatch.count('.')) * density
|
||
|
|
Circles.__init__(self, hatch, density)
|
||
|
|
|
||
|
|
|
||
|
|
class Stars(Shapes):
|
||
|
|
size = 1.0 / 3.0
|
||
|
|
filled = True
|
||
|
|
|
||
|
|
def __init__(self, hatch, density):
|
||
|
|
self.num_rows = (hatch.count('*')) * density
|
||
|
|
path = Path.unit_regular_star(5)
|
||
|
|
self.shape_vertices = path.vertices
|
||
|
|
self.shape_codes = np.full(len(self.shape_vertices), Path.LINETO,
|
||
|
|
dtype=Path.code_type)
|
||
|
|
self.shape_codes[0] = Path.MOVETO
|
||
|
|
Shapes.__init__(self, hatch, density)
|
||
|
|
|
||
|
|
_hatch_types = [
|
||
|
|
HorizontalHatch,
|
||
|
|
VerticalHatch,
|
||
|
|
NorthEastHatch,
|
||
|
|
SouthEastHatch,
|
||
|
|
SmallCircles,
|
||
|
|
LargeCircles,
|
||
|
|
SmallFilledCircles,
|
||
|
|
Stars
|
||
|
|
]
|
||
|
|
|
||
|
|
|
||
|
|
def get_path(hatchpattern, density=6):
|
||
|
|
"""
|
||
|
|
Given a hatch specifier, *hatchpattern*, generates Path to render
|
||
|
|
the hatch in a unit square. *density* is the number of lines per
|
||
|
|
unit square.
|
||
|
|
"""
|
||
|
|
density = int(density)
|
||
|
|
|
||
|
|
patterns = [hatch_type(hatchpattern, density)
|
||
|
|
for hatch_type in _hatch_types]
|
||
|
|
num_vertices = sum([pattern.num_vertices for pattern in patterns])
|
||
|
|
|
||
|
|
if num_vertices == 0:
|
||
|
|
return Path(np.empty((0, 2)))
|
||
|
|
|
||
|
|
vertices = np.empty((num_vertices, 2))
|
||
|
|
codes = np.empty(num_vertices, Path.code_type)
|
||
|
|
|
||
|
|
cursor = 0
|
||
|
|
for pattern in patterns:
|
||
|
|
if pattern.num_vertices != 0:
|
||
|
|
vertices_chunk = vertices[cursor:cursor + pattern.num_vertices]
|
||
|
|
codes_chunk = codes[cursor:cursor + pattern.num_vertices]
|
||
|
|
pattern.set_vertices_and_codes(vertices_chunk, codes_chunk)
|
||
|
|
cursor += pattern.num_vertices
|
||
|
|
|
||
|
|
return Path(vertices, codes)
|