"""Defines mutations."""
from random import randint, random
[docs]def simple_mutation(image, base_image, sequence, calculate_error, palette, draw):
"""Computes the effects of a simple mutation.
:param image: The image to draw the gene on.
:param base_image: The original image to compare to.
:param sequence: The gene sequence.
:param calculate_error: The error metric method.
:param palette: The color palette to use.
:param draw: The method to draw the shape according to the gene.
:type image: ndarray
:type base_image: ndarray
:type sequence: List[Gene]
:type calculate_error: Callable
:type palette: List[Tuple[int, int, int]]
:type draw: Callable
:return: The error, the mutated gene, and the new image.
:rtype: Tuple[float, Gene, ndarray]
"""
mutated_gene = sequence[0].clone()
mutated_gene.mutate()
new_image = image.copy()
draw(new_image, mutated_gene, palette)
error = calculate_error(new_image, base_image)
return error, mutated_gene, new_image
[docs]def complex_mutation(ancestor_image, base_image, sequence, num_shapes, calculate_error, palette, draw):
"""Computes the effects of a complex mutation.
:param ancestor_image: An image with the solid background color only.
:param base_image: The original image for comparison.
:param sequence: The existing gene sequence.
:param num_shapes: The number of shapes to draw.
:param calculate_error: The error metric method.
:param palette: The color palette to use.
:param draw: The method to draw the shape according to the gene.
:type ancestor_image: ndarray
:type base_image: ndarray
:type sequence: List[Gene]
:type num_shapes: int
:type calculate_error: Callable
:type palette: List[Tuple[int, int, int]]
:type draw: Callable
:return: The error, the mutated gene, the new image, the index of the mutated gene, whether mutated gene was placed on top.
:rtype: Tuple[float, Gene, ndarray, int, bool]
"""
mutation_index = randint(0, num_shapes - 1)
mutated_gene = sequence[mutation_index].clone()
mutated_gene.mutate()
new_image = ancestor_image.copy()
if random() > 0.5:
for index, gene in enumerate(sequence):
if index != mutation_index:
draw(new_image, gene, palette)
draw(new_image, mutated_gene, palette)
top = True
else:
for index, gene in enumerate(sequence):
if index == mutation_index:
draw(new_image, mutated_gene, palette)
else:
draw(new_image, gene, palette)
top = False
error = calculate_error(new_image, base_image)
return error, mutated_gene, new_image, mutation_index, top
