3b1b-manim/manimlib/mobject/svg/mtex_mobject.py
2022-01-26 13:03:14 +08:00

549 lines
20 KiB
Python

import itertools as it
import re
from types import MethodType
from manimlib.mobject.svg.svg_mobject import SVGMobject
from manimlib.mobject.types.vectorized_mobject import VMobject
from manimlib.mobject.types.vectorized_mobject import VGroup
from manimlib.utils.iterables import adjacent_pairs
from manimlib.utils.iterables import remove_list_redundancies
from manimlib.utils.tex_file_writing import tex_to_svg_file
from manimlib.utils.tex_file_writing import get_tex_config
from manimlib.utils.tex_file_writing import display_during_execution
SCALE_FACTOR_PER_FONT_POINT = 0.001
TEX_HASH_TO_MOB_MAP = {}
def _contains(span_0, span_1):
return span_0[0] <= span_1[0] and span_1[1] <= span_0[1]
def _get_neighbouring_pairs(iterable):
return list(adjacent_pairs(iterable))[:-1]
class _PlainTex(SVGMobject):
CONFIG = {
"height": None,
"path_string_config": {
"should_subdivide_sharp_curves": True,
"should_remove_null_curves": True,
},
}
class _LabelledTex(_PlainTex):
@staticmethod
def color_str_to_label(color_str):
if len(color_str) == 4:
# "#RGB" => "#RRGGBB"
color_str = "#" + "".join([c * 2 for c in color_str[1:]])
return int(color_str[1:], 16)
def get_mobjects_from(self, element):
result = super().get_mobjects_from(element)
for mob in result:
if not hasattr(mob, "glyph_label"):
mob.glyph_label = 0
try:
color_str = element.getAttribute("fill")
if color_str:
glyph_label = _LabelledTex.color_str_to_label(color_str)
for mob in result:
mob.glyph_label = glyph_label
except:
pass
return result
class _TexSpan(object):
def __init__(self, script_type, label):
# `script_type`: 0 for normal, 1 for subscript, 2 for superscript.
# Only those spans with `script_type == 0` will be colored.
self.script_type = script_type
self.label = label
self.containing_labels = []
def __repr__(self):
return "_TexSpan(" + ", ".join([
attrib_name + "=" + str(getattr(self, attrib_name))
for attrib_name in ["script_type", "label", "containing_labels"]
]) + ")"
class _TexParser(object):
def __init__(self, mtex):
self.tex_string = mtex.tex_string
self.tex_spans_dict = {}
self.current_label = 0
self.add_tex_span((0, len(self.tex_string)))
self.break_up_by_braces()
self.break_up_by_scripts()
self.break_up_by_additional_strings(mtex.strings_to_break_up)
self.merge_unbreakable_commands(mtex.unbreakable_commands)
self.analyse_containing_labels()
@staticmethod
def label_to_color_tuple(rgb):
# Get a unique color different from black,
# or the svg file will not include the color information.
rg, b = divmod(rgb, 256)
r, g = divmod(rg, 256)
return r, g, b
def add_tex_span(self, span_tuple, script_type=0, label=-1):
if script_type == 0:
# Should be additionally labelled.
label = self.current_label
self.current_label += 1
tex_span = _TexSpan(script_type, label)
self.tex_spans_dict[span_tuple] = tex_span
def break_up_by_braces(self):
tex_string = self.tex_string
span_tuples = []
left_brace_indices = []
for match_obj in re.finditer(r"(\\*)(\{|\})", tex_string):
# Braces following even numbers of backslashes are counted.
if len(match_obj.group(1)) % 2 == 1:
continue
if match_obj.group(2) == "{":
left_brace_index = match_obj.span(2)[0]
left_brace_indices.append(left_brace_index)
else:
left_brace_index = left_brace_indices.pop()
right_brace_index = match_obj.span(2)[1]
span_tuples.append((left_brace_index, right_brace_index))
if left_brace_indices:
self.raise_tex_parsing_error()
self.paired_braces_tuples = span_tuples
for span_tuple in span_tuples:
self.add_tex_span(span_tuple)
def break_up_by_scripts(self):
tex_string = self.tex_string
brace_indices_dict = dict(self.tex_spans_dict.keys())
for match_obj in re.finditer(r"((?<!\\)(_|\^)\s*)|(\s+(_|\^)\s*)", tex_string):
script_type = 1 if "_" in match_obj.group() else 2
token_begin, token_end = match_obj.span()
if token_end in brace_indices_dict:
content_span = (token_end, brace_indices_dict[token_end])
else:
content_match_obj = re.match(r"\w|\\[a-zA-Z]+", tex_string[token_end:])
if not content_match_obj:
self.raise_tex_parsing_error()
content_span = tuple([
index + token_end for index in content_match_obj.span()
])
self.add_tex_span(content_span)
label = self.tex_spans_dict[content_span].label
self.add_tex_span(
(token_begin, content_span[1]),
script_type=script_type,
label=label
)
def break_up_by_additional_strings(self, strings_to_break_up):
tex_string = self.tex_string
all_span_tuples = []
for string in strings_to_break_up:
# Only matches non-crossing strings.
for match_obj in re.finditer(re.escape(string), tex_string):
all_span_tuples.append(match_obj.span())
script_spans_dict = dict([
span_tuple[::-1]
for span_tuple, tex_span in self.tex_spans_dict.items()
if tex_span.script_type != 0
])
for span_begin, span_end in all_span_tuples:
if span_end in script_spans_dict.values():
# Deconstruct spans with subscripts & superscripts.
while span_end in script_spans_dict:
span_end = script_spans_dict[span_end]
if span_begin >= span_end:
continue
span_tuple = (span_begin, span_end)
if span_tuple not in self.tex_spans_dict:
self.add_tex_span(span_tuple)
def merge_unbreakable_commands(self, unbreakable_commands):
tex_string = self.tex_string
command_merge_spans = []
brace_indices_dict = dict(self.paired_braces_tuples)
# Braces leading by `unbreakable_commands` shouldn't be marked.
for command in unbreakable_commands:
for match_obj in re.finditer(re.escape(command), tex_string):
merge_begin_index = match_obj.span()[1]
merge_end_index = merge_begin_index
if merge_end_index not in brace_indices_dict:
continue
while merge_end_index in brace_indices_dict:
merge_end_index = brace_indices_dict[merge_end_index]
command_merge_spans.append((merge_begin_index, merge_end_index))
self.tex_spans_dict = {
span_tuple: tex_span
for span_tuple, tex_span in self.tex_spans_dict.items()
if all([
not _contains(merge_span, span_tuple)
for merge_span in command_merge_spans
])
}
def analyse_containing_labels(self):
for span_0, tex_span_0 in self.tex_spans_dict.items():
if tex_span_0.script_type != 0:
continue
for span_1, tex_span_1 in self.tex_spans_dict.items():
if _contains(span_1, span_0):
tex_span_1.containing_labels.append(tex_span_0.label)
def get_labelled_expression(self):
tex_string = self.tex_string
if not self.tex_spans_dict:
return tex_string
# Remove the span of extire tex string.
indices_with_labels = sorted([
(span_tuple[i], i, span_tuple[1 - i], tex_span.label)
for span_tuple, tex_span in self.tex_spans_dict.items()
if tex_span.script_type == 0
for i in range(2)
], key=lambda t: (t[0], -t[1], -t[2]))[1:]
result = tex_string[: indices_with_labels[0][0]]
index_with_label_pairs = _get_neighbouring_pairs(indices_with_labels)
for index_with_label, next_index_with_label in index_with_label_pairs:
index, flag, _, label = index_with_label
next_index, *_ = next_index_with_label
# Adding one more pair of braces will help maintain the glyghs of tex file...
if flag == 0:
color_tuple = _TexParser.label_to_color_tuple(label)
result += "".join([
"{{",
"\\color[RGB]",
"{",
",".join(map(str, color_tuple)),
"}"
])
else:
result += "}}"
result += tex_string[index : next_index]
return result
def raise_tex_parsing_error(self):
raise ValueError(f"Failed to parse tex: \"{self.tex_string}\"")
class MTex(VMobject):
CONFIG = {
"fill_opacity": 1.0,
"stroke_width": 0,
"font_size": 48,
"alignment": "\\centering",
"tex_environment": "align*",
"isolate": [],
"tex_to_color_map": {},
"unbreakable_commands": ["\\begin", "\\end"],
"generate_plain_tex_file": False,
}
def __init__(self, tex_string, **kwargs):
super().__init__(**kwargs)
tex_string = tex_string.strip()
# Prevent from passing an empty string.
if not tex_string:
tex_string = " "
self.tex_string = tex_string
self.set_strings_to_break_up()
self.generate_mobject()
self.init_colors()
self.set_color_by_tex_to_color_map(self.tex_to_color_map)
scale_factor = SCALE_FACTOR_PER_FONT_POINT * self.font_size
self.scale(scale_factor)
def set_strings_to_break_up(self):
strings_to_break_up = remove_list_redundancies([
*self.isolate, *self.tex_to_color_map.keys()
])
if "" in strings_to_break_up:
strings_to_break_up.remove("")
self.strings_to_break_up = strings_to_break_up
def generate_mobject(self):
tex_parser = _TexParser(self)
self.tex_spans_dict = tex_parser.tex_spans_dict
plain_full_tex = self.get_tex_file_body(self.tex_string)
plain_hash_val = hash(plain_full_tex)
if plain_hash_val in TEX_HASH_TO_MOB_MAP:
self.add(*TEX_HASH_TO_MOB_MAP[plain_hash_val].copy())
return self
labelled_expression = tex_parser.get_labelled_expression()
full_tex = self.get_tex_file_body(labelled_expression)
hash_val = hash(full_tex)
if hash_val in TEX_HASH_TO_MOB_MAP and not self.generate_plain_tex_file:
self.add(*TEX_HASH_TO_MOB_MAP[hash_val].copy())
return self
with display_during_execution(f"Writing \"{self.tex_string}\""):
filename = tex_to_svg_file(full_tex)
svg_mob = _LabelledTex(filename)
self.add(*svg_mob.copy())
self.build_submobjects()
TEX_HASH_TO_MOB_MAP[hash_val] = self
if not self.generate_plain_tex_file:
return self
with display_during_execution(f"Writing \"{self.tex_string}\""):
filename = tex_to_svg_file(plain_full_tex)
plain_svg_mob = _PlainTex(filename)
svg_mob = TEX_HASH_TO_MOB_MAP[hash_val]
for plain_submob, submob in zip(plain_svg_mob, svg_mob):
plain_submob.glyph_label = submob.glyph_label
self.add(*plain_svg_mob.copy())
self.build_submobjects()
TEX_HASH_TO_MOB_MAP[plain_hash_val] = self
return self
def get_tex_file_body(self, new_tex):
if self.tex_environment:
new_tex = "\n".join([
f"\\begin{{{self.tex_environment}}}",
new_tex,
f"\\end{{{self.tex_environment}}}"
])
if self.alignment:
new_tex = "\n".join([self.alignment, new_tex])
tex_config = get_tex_config()
return tex_config["tex_body"].replace(
tex_config["text_to_replace"],
new_tex
)
def build_submobjects(self):
if not self.submobjects:
return
self.group_submobjects()
self.sort_scripts_in_tex_order()
self.assign_submob_tex_strings()
def group_submobjects(self):
# Simply pack together adjacent mobjects with the same label.
new_submobjects = []
def append_new_submobject(glyphs):
if glyphs:
submobject = VGroup(*glyphs)
submobject.submob_label = glyphs[0].glyph_label
new_submobjects.append(submobject)
new_glyphs = []
current_glyph_label = 0
for submob in self.submobjects:
if submob.glyph_label == current_glyph_label:
new_glyphs.append(submob)
else:
append_new_submobject(new_glyphs)
new_glyphs = [submob]
current_glyph_label = submob.glyph_label
append_new_submobject(new_glyphs)
self.set_submobjects(new_submobjects)
def sort_scripts_in_tex_order(self):
# LaTeX always puts superscripts before subscripts.
# This function sorts the submobjects of scripts in the order of tex given.
index_and_span_list = sorted([
(index, span_tuple)
for span_tuple, tex_span in self.tex_spans_dict.items()
if tex_span.script_type != 0
for index in span_tuple
])
index_and_span_pairs = _get_neighbouring_pairs(index_and_span_list)
switch_range_pairs = []
for index_and_span_0, index_and_span_1 in index_and_span_pairs:
index_0, span_tuple_0 = index_and_span_0
index_1, span_tuple_1 = index_and_span_1
if index_0 != index_1:
continue
if not all([
self.tex_spans_dict[span_tuple_0].script_type == 1,
self.tex_spans_dict[span_tuple_1].script_type == 2
]):
continue
submob_range_0 = self.range_of_part(
self.get_part_by_span_tuples([span_tuple_0])
)
submob_range_1 = self.range_of_part(
self.get_part_by_span_tuples([span_tuple_1])
)
switch_range_pairs.append((submob_range_0, submob_range_1))
switch_range_pairs.sort(key=lambda pair: (pair[0].stop, -pair[0].start))
indices = list(range(len(self.submobjects)))
for submob_range_0, submob_range_1 in switch_range_pairs:
indices = [
*indices[: submob_range_1.start],
*indices[submob_range_0.start : submob_range_0.stop],
*indices[submob_range_1.stop : submob_range_0.start],
*indices[submob_range_1.start : submob_range_1.stop],
*indices[submob_range_0.stop :]
]
submobs = self.submobjects
self.set_submobjects([submobs[i] for i in indices])
def assign_submob_tex_strings(self):
# Not sure whether this is the best practice...
# This temporarily supports `TransformMatchingTex`.
tex_string = self.tex_string
# Use tex strings including "_", "^".
label_dict = {}
for span_tuple, tex_span in self.tex_spans_dict.items():
if tex_span.script_type != 0:
label_dict[tex_span.label] = span_tuple
else:
if tex_span.label not in label_dict:
label_dict[tex_span.label] = span_tuple
curr_labels = [submob.submob_label for submob in self.submobjects]
prev_labels = [curr_labels[-1], *curr_labels[:-1]]
next_labels = [*curr_labels[1:], curr_labels[0]]
tex_string_spans = []
for curr_label, prev_label, next_label in zip(
curr_labels, prev_labels, next_labels
):
curr_span_tuple = label_dict[curr_label]
prev_span_tuple = label_dict[prev_label]
next_span_tuple = label_dict[next_label]
containing_labels = self.tex_spans_dict[curr_span_tuple].containing_labels
tex_string_spans.append([
prev_span_tuple[1] if prev_label in containing_labels else curr_span_tuple[0],
next_span_tuple[0] if next_label in containing_labels else curr_span_tuple[1]
])
tex_string_spans[0][0] = label_dict[curr_labels[0]][0]
tex_string_spans[-1][1] = label_dict[curr_labels[-1]][1]
for submob, tex_string_span in zip(self.submobjects, tex_string_spans):
submob.tex_string = tex_string[slice(*tex_string_span)]
# Support `get_tex()` method here.
submob.get_tex = MethodType(lambda inst: inst.tex_string, submob)
def get_part_by_span_tuples(self, span_tuples):
labels = remove_list_redundancies(list(it.chain(*[
self.tex_spans_dict[span_tuple].containing_labels
for span_tuple in span_tuples
])))
return VGroup(*filter(
lambda submob: submob.submob_label in labels,
self.submobjects
))
def find_span_components_of_custom_span(self, custom_span_tuple, partial_result=[]):
span_begin, span_end = custom_span_tuple
if span_begin == span_end:
return partial_result
next_begin_choices = sorted([
span_tuple[1]
for span_tuple in self.tex_spans_dict.keys()
if span_tuple[0] == span_begin and span_tuple[1] <= span_end
], reverse=True)
for next_begin in next_begin_choices:
result = self.find_span_components_of_custom_span(
(next_begin, span_end), [*partial_result, (span_begin, next_begin)]
)
if result is not None:
return result
return None
def get_part_by_custom_span_tuple(self, custom_span_tuple):
span_tuples = self.find_span_components_of_custom_span(custom_span_tuple)
if span_tuples is None:
tex = self.tex_string[slice(*custom_span_tuple)]
raise ValueError(f"Failed to get span of tex: \"{tex}\"")
return self.get_part_by_span_tuples(span_tuples)
def get_parts_by_tex(self, tex):
return VGroup(*[
self.get_part_by_custom_span_tuple(match_obj.span())
for match_obj in re.finditer(re.escape(tex), self.tex_string)
])
def get_part_by_tex(self, tex, index=0):
all_parts = self.get_parts_by_tex(tex)
return all_parts[index]
def set_color_by_tex(self, tex, color):
self.get_parts_by_tex(tex).set_color(color)
return self
def set_color_by_tex_to_color_map(self, tex_to_color_map):
for tex, color in list(tex_to_color_map.items()):
try:
self.set_color_by_tex(tex, color)
except:
pass
return self
def indices_of_part(self, part):
indices = [
i for i, submob in enumerate(self.submobjects)
if submob in part
]
if not indices:
raise ValueError("Failed to find part in tex")
return indices
def indices_of_part_by_tex(self, tex, index=0):
part = self.get_part_by_tex(tex, index=index)
return self.indices_of_part(part)
def range_of_part(self, part):
indices = self.indices_of_part(part)
return range(indices[0], indices[-1] + 1)
def range_of_part_by_tex(self, tex, index=0):
part = self.get_part_by_tex(tex, index=index)
return self.range_of_part(part)
def index_of_part(self, part):
return self.indices_of_part(part)[0]
def index_of_part_by_tex(self, tex, index=0):
part = self.get_part_by_tex(tex, index=index)
return self.index_of_part(part)
def get_tex(self):
return self.tex_string
def get_all_isolated_substrings(self):
tex_string = self.tex_string
return remove_list_redundancies([
tex_string[slice(*span_tuple)]
for span_tuple in self.tex_spans_dict.keys()
])
def print_tex_strings_of_submobjects(self):
# For debugging
# Work with `index_labels()`
print("\n")
print(f"Submobjects of \"{self.get_tex()}\":")
for i, submob in enumerate(self.submobjects):
print(f"{i}: \"{submob.get_tex()}\"")
print("\n")
class MTexText(MTex):
CONFIG = {
"tex_environment": None,
}