"""Mobjects used for displaying (non-LaTeX) text.
.. note::
Just as you can use :class:`~.Tex` and :class:`~.MathTex` (from the module :mod:`~.tex_mobject`)
to insert LaTeX to your videos, you can use :class:`~.Text` to to add normal text.
.. important::
See the corresponding tutorial :ref:`using-text-objects`, especially for information about fonts.
The simplest way to add text to your animations is to use the :class:`~.Text` class. It uses the Pango library to render text.
With Pango, you are also able to render non-English alphabets like `你好` or `こんにちは` or `안녕하세요` or `مرحبا بالعالم`.
Examples
--------
.. manim:: HelloWorld
:save_last_frame:
class HelloWorld(Scene):
def construct(self):
text = Text('Hello world').scale(3)
self.add(text)
.. manim:: TextAlignment
:save_last_frame:
class TextAlignment(Scene):
def construct(self):
title = Text("K-means clustering and Logistic Regression", color=WHITE)
title.scale(0.75)
self.add(title.to_edge(UP))
t1 = Text("1. Measuring").set_color(WHITE)
t2 = Text("2. Clustering").set_color(WHITE)
t3 = Text("3. Regression").set_color(WHITE)
t4 = Text("4. Prediction").set_color(WHITE)
x = VGroup(t1, t2, t3, t4).arrange(direction=DOWN, aligned_edge=LEFT).scale(0.7).next_to(ORIGIN,DR)
x.set_opacity(0.5)
x.submobjects[1].set_opacity(1)
self.add(x)
"""
from __future__ import annotations
__all__ = ["Text", "Paragraph", "MarkupText", "register_font"]
import copy
import hashlib
import os
import re
from contextlib import contextmanager
from itertools import chain
from pathlib import Path
from typing import Iterable, Sequence
import manimpango
import numpy as np
from manimpango import MarkupUtils, PangoUtils, TextSetting
from manim import config, logger
from manim.constants import *
from manim.mobject.geometry.arc import Dot
from manim.mobject.svg.svg_mobject import SVGMobject
from manim.mobject.types.vectorized_mobject import VGroup, VMobject
from manim.utils.color import ManimColor, ParsableManimColor, color_gradient
from manim.utils.deprecation import deprecated
TEXT_MOB_SCALE_FACTOR = 0.05
DEFAULT_LINE_SPACING_SCALE = 0.3
TEXT2SVG_ADJUSTMENT_FACTOR = 4.8
[docs]def remove_invisible_chars(mobject: SVGMobject) -> SVGMobject:
"""Function to remove unwanted invisible characters from some mobjects.
Parameters
----------
mobject
Any SVGMobject from which we want to remove unwanted invisible characters.
Returns
-------
:class:`~.SVGMobject`
The SVGMobject without unwanted invisible characters.
"""
# TODO: Refactor needed
iscode = False
if mobject.__class__.__name__ == "Text":
mobject = mobject[:]
elif mobject.__class__.__name__ == "Code":
iscode = True
code = mobject
mobject = mobject.code
mobject_without_dots = VGroup()
if mobject[0].__class__ == VGroup:
for i in range(len(mobject)):
mobject_without_dots.add(VGroup())
mobject_without_dots[i].add(*(k for k in mobject[i] if k.__class__ != Dot))
else:
mobject_without_dots.add(*(k for k in mobject if k.__class__ != Dot))
if iscode:
code.code = mobject_without_dots
return code
return mobject_without_dots
[docs]class Paragraph(VGroup):
r"""Display a paragraph of text.
For a given :class:`.Paragraph` ``par``, the attribute ``par.chars`` is a
:class:`.VGroup` containing all the lines. In this context, every line is
constructed as a :class:`.VGroup` of characters contained in the line.
Parameters
----------
line_spacing
Represents the spacing between lines. Defaults to -1, which means auto.
alignment
Defines the alignment of paragraph. Defaults to None. Possible values are "left", "right" or "center".
Examples
--------
Normal usage::
paragraph = Paragraph('this is a awesome', 'paragraph',
'With \nNewlines', '\tWith Tabs',
' With Spaces', 'With Alignments',
'center', 'left', 'right')
Remove unwanted invisible characters::
self.play(Transform(remove_invisible_chars(paragraph.chars[0:2]),
remove_invisible_chars(paragraph.chars[3][0:3]))
"""
def __init__(
self,
*text: Sequence[str],
line_spacing: float = -1,
alignment: str | None = None,
**kwargs,
) -> None:
self.line_spacing = line_spacing
self.alignment = alignment
self.consider_spaces_as_chars = kwargs.get("disable_ligatures", False)
super().__init__()
lines_str = "\n".join(list(text))
self.lines_text = Text(lines_str, line_spacing=line_spacing, **kwargs)
lines_str_list = lines_str.split("\n")
self.chars = self._gen_chars(lines_str_list)
self.lines = [list(self.chars), [self.alignment] * len(self.chars)]
self.lines_initial_positions = [line.get_center() for line in self.lines[0]]
self.add(*self.lines[0])
self.move_to(np.array([0, 0, 0]))
if self.alignment:
self._set_all_lines_alignments(self.alignment)
[docs] def _gen_chars(self, lines_str_list: list) -> VGroup:
"""Function to convert a list of plain strings to a VGroup of VGroups of chars.
Parameters
----------
lines_str_list
List of plain text strings.
Returns
-------
:class:`~.VGroup`
The generated 2d-VGroup of chars.
"""
char_index_counter = 0
chars = self.get_group_class()()
for line_no in range(len(lines_str_list)):
line_str = lines_str_list[line_no]
# Count all the characters in line_str
# Spaces may or may not count as characters
if self.consider_spaces_as_chars:
char_count = len(line_str)
else:
char_count = 0
for char in line_str:
if not char.isspace():
char_count += 1
chars.add(self.get_group_class()())
chars[line_no].add(
*self.lines_text.chars[
char_index_counter : char_index_counter + char_count
]
)
char_index_counter += char_count
if self.consider_spaces_as_chars:
# If spaces count as characters, count the extra \n character
# which separates Paragraph's lines to avoid issues
char_index_counter += 1
return chars
[docs] def _set_all_lines_alignments(self, alignment: str) -> Paragraph:
"""Function to set all line's alignment to a specific value.
Parameters
----------
alignment
Defines the alignment of paragraph. Possible values are "left", "right", "center".
"""
for line_no in range(len(self.lines[0])):
self._change_alignment_for_a_line(alignment, line_no)
return self
[docs] def _set_line_alignment(self, alignment: str, line_no: int) -> Paragraph:
"""Function to set one line's alignment to a specific value.
Parameters
----------
alignment
Defines the alignment of paragraph. Possible values are "left", "right", "center".
line_no
Defines the line number for which we want to set given alignment.
"""
self._change_alignment_for_a_line(alignment, line_no)
return self
[docs] def _set_all_lines_to_initial_positions(self) -> Paragraph:
"""Set all lines to their initial positions."""
self.lines[1] = [None] * len(self.lines[0])
for line_no in range(len(self.lines[0])):
self[line_no].move_to(
self.get_center() + self.lines_initial_positions[line_no],
)
return self
[docs] def _set_line_to_initial_position(self, line_no: int) -> Paragraph:
"""Function to set one line to initial positions.
Parameters
----------
line_no
Defines the line number for which we want to set given alignment.
"""
self.lines[1][line_no] = None
self[line_no].move_to(self.get_center() + self.lines_initial_positions[line_no])
return self
[docs] def _change_alignment_for_a_line(self, alignment: str, line_no: int) -> None:
"""Function to change one line's alignment to a specific value.
Parameters
----------
alignment
Defines the alignment of paragraph. Possible values are "left", "right", "center".
line_no
Defines the line number for which we want to set given alignment.
"""
self.lines[1][line_no] = alignment
if self.lines[1][line_no] == "center":
self[line_no].move_to(
np.array([self.get_center()[0], self[line_no].get_center()[1], 0]),
)
elif self.lines[1][line_no] == "right":
self[line_no].move_to(
np.array(
[
self.get_right()[0] - self[line_no].width / 2,
self[line_no].get_center()[1],
0,
],
),
)
elif self.lines[1][line_no] == "left":
self[line_no].move_to(
np.array(
[
self.get_left()[0] + self[line_no].width / 2,
self[line_no].get_center()[1],
0,
],
),
)
[docs]class Text(SVGMobject):
r"""Display (non-LaTeX) text rendered using `Pango <https://pango.gnome.org/>`_.
Text objects behave like a :class:`.VGroup`-like iterable of all characters
in the given text. In particular, slicing is possible.
Parameters
----------
text
The text that needs to be created as a mobject.
font
The font family to be used to render the text. This is either a system font or
one loaded with `register_font()`. Note that font family names may be different
across operating systems.
warn_missing_font
If True (default), Manim will issue a warning if the font does not exist in the
(case-sensitive) list of fonts returned from `manimpango.list_fonts()`.
Returns
-------
:class:`Text`
The mobject-like :class:`.VGroup`.
Examples
---------
.. manim:: Example1Text
:save_last_frame:
class Example1Text(Scene):
def construct(self):
text = Text('Hello world').scale(3)
self.add(text)
.. manim:: TextColorExample
:save_last_frame:
class TextColorExample(Scene):
def construct(self):
text1 = Text('Hello world', color=BLUE).scale(3)
text2 = Text('Hello world', gradient=(BLUE, GREEN)).scale(3).next_to(text1, DOWN)
self.add(text1, text2)
.. manim:: TextItalicAndBoldExample
:save_last_frame:
class TextItalicAndBoldExample(Scene):
def construct(self):
text1 = Text("Hello world", slant=ITALIC)
text2 = Text("Hello world", t2s={'world':ITALIC})
text3 = Text("Hello world", weight=BOLD)
text4 = Text("Hello world", t2w={'world':BOLD})
text5 = Text("Hello world", t2c={'o':YELLOW}, disable_ligatures=True)
text6 = Text(
"Visit us at docs.manim.community",
t2c={"docs.manim.community": YELLOW},
disable_ligatures=True,
)
text6.scale(1.3).shift(DOWN)
self.add(text1, text2, text3, text4, text5 , text6)
Group(*self.mobjects).arrange(DOWN, buff=.8).set_height(config.frame_height-LARGE_BUFF)
.. manim:: TextMoreCustomization
:save_last_frame:
class TextMoreCustomization(Scene):
def construct(self):
text1 = Text(
'Google',
t2c={'[:1]': '#3174f0', '[1:2]': '#e53125',
'[2:3]': '#fbb003', '[3:4]': '#3174f0',
'[4:5]': '#269a43', '[5:]': '#e53125'}, font_size=58).scale(3)
self.add(text1)
As :class:`Text` uses Pango to render text, rendering non-English
characters is easily possible:
.. manim:: MultipleFonts
:save_last_frame:
class MultipleFonts(Scene):
def construct(self):
morning = Text("வணக்கம்", font="sans-serif")
japanese = Text(
"日本へようこそ", t2c={"日本": BLUE}
) # works same as ``Text``.
mess = Text("Multi-Language", weight=BOLD)
russ = Text("Здравствуйте मस नम म ", font="sans-serif")
hin = Text("नमस्ते", font="sans-serif")
arb = Text(
"صباح الخير \n تشرفت بمقابلتك", font="sans-serif"
) # don't mix RTL and LTR languages nothing shows up then ;-)
chinese = Text("臂猿「黛比」帶著孩子", font="sans-serif")
self.add(morning, japanese, mess, russ, hin, arb, chinese)
for i,mobj in enumerate(self.mobjects):
mobj.shift(DOWN*(i-3))
.. manim:: PangoRender
:quality: low
class PangoRender(Scene):
def construct(self):
morning = Text("வணக்கம்", font="sans-serif")
self.play(Write(morning))
self.wait(2)
Tests
-----
Check that the creation of :class:`~.Text` works::
>>> Text('The horse does not eat cucumber salad.')
Text('The horse does not eat cucumber salad.')
"""
def __init__(
self,
text: str,
fill_opacity: float = 1.0,
stroke_width: float = 0,
color: ParsableManimColor | None = None,
font_size: float = DEFAULT_FONT_SIZE,
line_spacing: float = -1,
font: str = "",
slant: str = NORMAL,
weight: str = NORMAL,
t2c: dict[str, str] = None,
t2f: dict[str, str] = None,
t2g: dict[str, tuple] = None,
t2s: dict[str, str] = None,
t2w: dict[str, str] = None,
gradient: tuple = None,
tab_width: int = 4,
warn_missing_font: bool = True,
# Mobject
height: float = None,
width: float = None,
should_center: bool = True,
disable_ligatures: bool = False,
**kwargs,
) -> None:
self.line_spacing = line_spacing
if font and warn_missing_font:
fonts_list = manimpango.list_fonts()
if font not in fonts_list:
logger.warning(f"Font {font} not in {fonts_list}.")
self.font = font
self._font_size = float(font_size)
# needs to be a float or else size is inflated when font_size = 24
# (unknown cause)
self.slant = slant
self.weight = weight
self.gradient = gradient
self.tab_width = tab_width
if t2c is None:
t2c = {}
if t2f is None:
t2f = {}
if t2g is None:
t2g = {}
if t2s is None:
t2s = {}
if t2w is None:
t2w = {}
# If long form arguments are present, they take precedence
t2c = kwargs.pop("text2color", t2c)
t2f = kwargs.pop("text2font", t2f)
t2g = kwargs.pop("text2gradient", t2g)
t2s = kwargs.pop("text2slant", t2s)
t2w = kwargs.pop("text2weight", t2w)
self.t2c = {k: ManimColor(v).to_hex() for k, v in t2c.items()}
self.t2f = t2f
self.t2g = t2g
self.t2s = t2s
self.t2w = t2w
self.original_text = text
self.disable_ligatures = disable_ligatures
text_without_tabs = text
if text.find("\t") != -1:
text_without_tabs = text.replace("\t", " " * self.tab_width)
self.text = text_without_tabs
if self.line_spacing == -1:
self.line_spacing = (
self._font_size + self._font_size * DEFAULT_LINE_SPACING_SCALE
)
else:
self.line_spacing = self._font_size + self._font_size * self.line_spacing
color: ManimColor = ManimColor(color) if color else VMobject().color
file_name = self._text2svg(color.to_hex())
PangoUtils.remove_last_M(file_name)
super().__init__(
file_name,
fill_opacity=fill_opacity,
stroke_width=stroke_width,
height=height,
width=width,
should_center=should_center,
use_svg_cache=False,
**kwargs,
)
self.text = text
if self.disable_ligatures:
self.submobjects = [*self._gen_chars()]
self.chars = self.get_group_class()(*self.submobjects)
self.text = text_without_tabs.replace(" ", "").replace("\n", "")
nppc = self.n_points_per_curve
for each in self:
if len(each.points) == 0:
continue
points = each.points
curve_start = points[0]
assert len(curve_start) == self.dim, curve_start
# Some of the glyphs in this text might not be closed,
# so we close them by identifying when one curve ends
# but it is not where the next curve starts.
# It is more efficient to temporarily create a list
# of points and add them one at a time, then turn them
# into a numpy array at the end, rather than creating
# new numpy arrays every time a point or fixing line
# is added (which is O(n^2) for numpy arrays).
closed_curve_points = []
# OpenGL has points be part of quadratic Bezier curves;
# Cairo uses cubic Bezier curves.
if nppc == 3: # RendererType.OPENGL
def add_line_to(end):
nonlocal closed_curve_points
start = closed_curve_points[-1]
closed_curve_points += [
start,
(start + end) / 2,
end,
]
else: # RendererType.CAIRO
def add_line_to(end):
nonlocal closed_curve_points
start = closed_curve_points[-1]
closed_curve_points += [
start,
(start + start + end) / 3,
(start + end + end) / 3,
end,
]
for index, point in enumerate(points):
closed_curve_points.append(point)
if (
index != len(points) - 1
and (index + 1) % nppc == 0
and any(point != points[index + 1])
):
# Add straight line from last point on this curve to the
# start point on the next curve. We represent the line
# as a cubic bezier curve where the two control points
# are half-way between the start and stop point.
add_line_to(curve_start)
curve_start = points[index + 1]
# Make sure last curve is closed
add_line_to(curve_start)
each.points = np.array(closed_curve_points, ndmin=2)
# anti-aliasing
if height is None and width is None:
self.scale(TEXT_MOB_SCALE_FACTOR)
self.initial_height = self.height
def __repr__(self):
return f"Text({repr(self.original_text)})"
@property
def font_size(self):
return (
self.height
/ self.initial_height
/ TEXT_MOB_SCALE_FACTOR
* 2.4
* self._font_size
/ DEFAULT_FONT_SIZE
)
@font_size.setter
def font_size(self, font_val):
# TODO: use pango's font size scaling.
if font_val <= 0:
raise ValueError("font_size must be greater than 0.")
else:
self.scale(font_val / self.font_size)
def _gen_chars(self):
chars = self.get_group_class()()
submobjects_char_index = 0
for char_index in range(len(self.text)):
if self.text[char_index].isspace():
space = Dot(radius=0, fill_opacity=0, stroke_opacity=0)
if char_index == 0:
space.move_to(self.submobjects[submobjects_char_index].get_center())
else:
space.move_to(
self.submobjects[submobjects_char_index - 1].get_center(),
)
chars.add(space)
else:
chars.add(self.submobjects[submobjects_char_index])
submobjects_char_index += 1
return chars
[docs] def _find_indexes(self, word: str, text: str):
"""Finds the indexes of ``text`` in ``word``."""
temp = re.match(r"\[([0-9\-]{0,}):([0-9\-]{0,})\]", word)
if temp:
start = int(temp.group(1)) if temp.group(1) != "" else 0
end = int(temp.group(2)) if temp.group(2) != "" else len(text)
start = len(text) + start if start < 0 else start
end = len(text) + end if end < 0 else end
return [(start, end)]
indexes = []
index = text.find(word)
while index != -1:
indexes.append((index, index + len(word)))
index = text.find(word, index + len(word))
return indexes
[docs] @deprecated(
since="v0.14.0",
until="v0.15.0",
message="This was internal function, you shouldn't be using it anyway.",
)
def _set_color_by_t2c(self, t2c=None):
"""Sets color for specified strings."""
t2c = t2c if t2c else self.t2c
for word, color in list(t2c.items()):
for start, end in self._find_indexes(word, self.text):
self.chars[start:end].set_color(color)
[docs] @deprecated(
since="v0.14.0",
until="v0.15.0",
message="This was internal function, you shouldn't be using it anyway.",
)
def _set_color_by_t2g(self, t2g=None):
"""Sets gradient colors for specified
strings. Behaves similarly to ``set_color_by_t2c``."""
t2g = t2g if t2g else self.t2g
for word, gradient in list(t2g.items()):
for start, end in self._find_indexes(word, self.text):
self.chars[start:end].set_color_by_gradient(*gradient)
[docs] def _text2hash(self, color: ManimColor):
"""Generates ``sha256`` hash for file name."""
settings = (
"PANGO" + self.font + self.slant + self.weight + str(color)
) # to differentiate Text and CairoText
settings += str(self.t2f) + str(self.t2s) + str(self.t2w) + str(self.t2c)
settings += str(self.line_spacing) + str(self._font_size)
settings += str(self.disable_ligatures)
id_str = self.text + settings
hasher = hashlib.sha256()
hasher.update(id_str.encode())
return hasher.hexdigest()[:16]
def _merge_settings(
self,
left_setting: TextSetting,
right_setting: TextSetting,
default_args: dict[str, Iterable[str]],
) -> TextSetting:
contained = right_setting.end < left_setting.end
new_setting = copy.copy(left_setting) if contained else copy.copy(right_setting)
new_setting.start = right_setting.end if contained else left_setting.end
left_setting.end = right_setting.start
if not contained:
right_setting.end = new_setting.start
for arg in default_args:
left = getattr(left_setting, arg)
right = getattr(right_setting, arg)
default = default_args[arg]
if left != default and getattr(right_setting, arg) != default:
raise ValueError(
f"Ambiguous style for text '{self.text[right_setting.start:right_setting.end]}':"
+ f"'{arg}' cannot be both '{left}' and '{right}'."
)
setattr(right_setting, arg, left if left != default else right)
return new_setting
def _get_settings_from_t2xs(
self,
t2xs: Sequence[tuple[dict[str, str], str]],
default_args: dict[str, Iterable[str]],
) -> Sequence[TextSetting]:
settings = []
t2xwords = set(chain(*([*t2x.keys()] for t2x, _ in t2xs)))
for word in t2xwords:
setting_args = {
arg: str(t2x[word]) if word in t2x else default_args[arg]
# NOTE: when t2x[word] is a ManimColor, str will yield the
# hex representation
for t2x, arg in t2xs
}
for start, end in self._find_indexes(word, self.text):
settings.append(TextSetting(start, end, **setting_args))
return settings
def _get_settings_from_gradient(
self, default_args: dict[str, Iterable[str]]
) -> Sequence[TextSetting]:
settings = []
args = copy.copy(default_args)
if self.gradient:
colors = color_gradient(self.gradient, len(self.text))
for i in range(len(self.text)):
args["color"] = colors[i].to_hex()
settings.append(TextSetting(i, i + 1, **args))
for word, gradient in self.t2g.items():
if isinstance(gradient, str) or len(gradient) == 1:
color = gradient if isinstance(gradient, str) else gradient[0]
gradient = [ManimColor(color)]
colors = (
color_gradient(gradient, len(word))
if len(gradient) != 1
else len(word) * gradient
)
for start, end in self._find_indexes(word, self.text):
for i in range(start, end):
args["color"] = colors[i - start].to_hex()
settings.append(TextSetting(i, i + 1, **args))
return settings
[docs] def _text2settings(self, color: str):
"""Converts the texts and styles to a setting for parsing."""
t2xs = [
(self.t2f, "font"),
(self.t2s, "slant"),
(self.t2w, "weight"),
(self.t2c, "color"),
]
# setting_args requires values to be strings
default_args = {
arg: getattr(self, arg) if arg != "color" else color for _, arg in t2xs
}
settings = self._get_settings_from_t2xs(t2xs, default_args)
settings.extend(self._get_settings_from_gradient(default_args))
# Handle overlaps
settings.sort(key=lambda setting: setting.start)
for index, setting in enumerate(settings):
if index + 1 == len(settings):
break
next_setting = settings[index + 1]
if setting.end > next_setting.start:
new_setting = self._merge_settings(setting, next_setting, default_args)
new_index = index + 1
while (
new_index < len(settings)
and settings[new_index].start < new_setting.start
):
new_index += 1
settings.insert(new_index, new_setting)
# Set all text settings (default font, slant, weight)
temp_settings = settings.copy()
start = 0
for setting in settings:
if setting.start != start:
temp_settings.append(TextSetting(start, setting.start, **default_args))
start = setting.end
if start != len(self.text):
temp_settings.append(TextSetting(start, len(self.text), **default_args))
settings = sorted(temp_settings, key=lambda setting: setting.start)
line_num = 0
if re.search(r"\n", self.text):
for start, end in self._find_indexes("\n", self.text):
for setting in settings:
if setting.line_num == -1:
setting.line_num = line_num
if start < setting.end:
line_num += 1
new_setting = copy.copy(setting)
setting.end = end
new_setting.start = end
new_setting.line_num = line_num
settings.append(new_setting)
settings.sort(key=lambda setting: setting.start)
break
for setting in settings:
if setting.line_num == -1:
setting.line_num = line_num
return settings
[docs] def _text2svg(self, color: ManimColor):
"""Convert the text to SVG using Pango."""
size = self._font_size
line_spacing = self.line_spacing
size /= TEXT2SVG_ADJUSTMENT_FACTOR
line_spacing /= TEXT2SVG_ADJUSTMENT_FACTOR
dir_name = config.get_dir("text_dir")
if not dir_name.is_dir():
dir_name.mkdir(parents=True)
hash_name = self._text2hash(color)
file_name = dir_name / (hash_name + ".svg")
if file_name.exists():
svg_file = str(file_name.resolve())
else:
settings = self._text2settings(color)
width = config["pixel_width"]
height = config["pixel_height"]
svg_file = manimpango.text2svg(
settings,
size,
line_spacing,
self.disable_ligatures,
str(file_name.resolve()),
START_X,
START_Y,
width,
height,
self.text,
)
return svg_file
[docs] def init_colors(self, propagate_colors=True):
if config.renderer == RendererType.OPENGL:
super().init_colors()
elif config.renderer == RendererType.CAIRO:
super().init_colors(propagate_colors=propagate_colors)
[docs]class MarkupText(SVGMobject):
r"""Display (non-LaTeX) text rendered using `Pango <https://pango.gnome.org/>`_.
Text objects behave like a :class:`.VGroup`-like iterable of all characters
in the given text. In particular, slicing is possible.
**What is PangoMarkup?**
PangoMarkup is a small markup language like html and it helps you avoid using
"range of characters" while coloring or styling a piece a Text. You can use
this language with :class:`~.MarkupText`.
A simple example of a marked-up string might be::
<span foreground="blue" size="x-large">Blue text</span> is <i>cool</i>!"
and it can be used with :class:`~.MarkupText` as
.. manim:: MarkupExample
:save_last_frame:
class MarkupExample(Scene):
def construct(self):
text = MarkupText('<span foreground="blue" size="x-large">Blue text</span> is <i>cool</i>!"')
self.add(text)
A more elaborate example would be:
.. manim:: MarkupElaborateExample
:save_last_frame:
class MarkupElaborateExample(Scene):
def construct(self):
text = MarkupText(
'<span foreground="purple">ا</span><span foreground="red">َ</span>'
'ل<span foreground="blue">ْ</span>ع<span foreground="red">َ</span>ر'
'<span foreground="red">َ</span>ب<span foreground="red">ِ</span>ي'
'<span foreground="green">ّ</span><span foreground="red">َ</span>ة'
'<span foreground="blue">ُ</span>'
)
self.add(text)
PangoMarkup can also contain XML features such as numeric character
entities such as ``©`` for © can be used too.
The most general markup tag is ``<span>``, then there are some
convenience tags.
Here is a list of supported tags:
- ``<b>bold</b>``, ``<i>italic</i>`` and ``<b><i>bold+italic</i></b>``
- ``<ul>underline</ul>`` and ``<s>strike through</s>``
- ``<tt>typewriter font</tt>``
- ``<big>bigger font</big>`` and ``<small>smaller font</small>``
- ``<sup>superscript</sup>`` and ``<sub>subscript</sub>``
- ``<span underline="double" underline_color="green">double underline</span>``
- ``<span underline="error">error underline</span>``
- ``<span overline="single" overline_color="green">overline</span>``
- ``<span strikethrough="true" strikethrough_color="red">strikethrough</span>``
- ``<span font_family="sans">temporary change of font</span>``
- ``<span foreground="red">temporary change of color</span>``
- ``<span fgcolor="red">temporary change of color</span>``
- ``<gradient from="YELLOW" to="RED">temporary gradient</gradient>``
For ``<span>`` markup, colors can be specified either as
hex triples like ``#aabbcc`` or as named CSS colors like
``AliceBlue``.
The ``<gradient>`` tag is handled by Manim rather than
Pango, and supports hex triplets or Manim constants like
``RED`` or ``RED_A``.
If you want to use Manim constants like ``RED_A`` together
with ``<span>``, you will need to use Python's f-String
syntax as follows::
MarkupText(f'<span foreground="{RED_A}">here you go</span>')
If your text contains ligatures, the :class:`MarkupText` class may
incorrectly determine the first and last letter when creating the
gradient. This is due to the fact that ``fl`` are two separate characters,
but might be set as one single glyph - a ligature. If your language
does not depend on ligatures, consider setting ``disable_ligatures``
to ``True``. If you must use ligatures, the ``gradient`` tag supports an optional
attribute ``offset`` which can be used to compensate for that error.
For example:
- ``<gradient from="RED" to="YELLOW" offset="1">example</gradient>`` to *start* the gradient one letter earlier
- ``<gradient from="RED" to="YELLOW" offset=",1">example</gradient>`` to *end* the gradient one letter earlier
- ``<gradient from="RED" to="YELLOW" offset="2,1">example</gradient>`` to *start* the gradient two letters earlier and *end* it one letter earlier
Specifying a second offset may be necessary if the text to be colored does
itself contain ligatures. The same can happen when using HTML entities for
special chars.
When using ``underline``, ``overline`` or ``strikethrough`` together with
``<gradient>`` tags, you will also need to use the offset, because
underlines are additional paths in the final :class:`SVGMobject`.
Check out the following example.
Escaping of special characters: ``>`` **should** be written as ``>``
whereas ``<`` and ``&`` *must* be written as ``<`` and
``&``.
You can find more information about Pango markup formatting at the
corresponding documentation page:
`Pango Markup <https://docs.gtk.org/Pango/pango_markup.html>`_.
Please be aware that not all features are supported by this class and that
the ``<gradient>`` tag mentioned above is not supported by Pango.
Parameters
----------
text
The text that needs to be created as mobject.
fill_opacity
The fill opacity, with 1 meaning opaque and 0 meaning transparent.
stroke_width
Stroke width.
font_size
Font size.
line_spacing
Line spacing.
font
Global font setting for the entire text. Local overrides are possible.
slant
Global slant setting, e.g. `NORMAL` or `ITALIC`. Local overrides are possible.
weight
Global weight setting, e.g. `NORMAL` or `BOLD`. Local overrides are possible.
gradient
Global gradient setting. Local overrides are possible.
warn_missing_font
If True (default), Manim will issue a warning if the font does not exist in the
(case-sensitive) list of fonts returned from `manimpango.list_fonts()`.
Returns
-------
:class:`MarkupText`
The text displayed in form of a :class:`.VGroup`-like mobject.
Examples
---------
.. manim:: BasicMarkupExample
:save_last_frame:
class BasicMarkupExample(Scene):
def construct(self):
text1 = MarkupText("<b>foo</b> <i>bar</i> <b><i>foobar</i></b>")
text2 = MarkupText("<s>foo</s> <u>bar</u> <big>big</big> <small>small</small>")
text3 = MarkupText("H<sub>2</sub>O and H<sub>3</sub>O<sup>+</sup>")
text4 = MarkupText("type <tt>help</tt> for help")
text5 = MarkupText(
'<span underline="double">foo</span> <span underline="error">bar</span>'
)
group = VGroup(text1, text2, text3, text4, text5).arrange(DOWN)
self.add(group)
.. manim:: ColorExample
:save_last_frame:
class ColorExample(Scene):
def construct(self):
text1 = MarkupText(
f'all in red <span fgcolor="{YELLOW}">except this</span>', color=RED
)
text2 = MarkupText("nice gradient", gradient=(BLUE, GREEN))
text3 = MarkupText(
'nice <gradient from="RED" to="YELLOW">intermediate</gradient> gradient',
gradient=(BLUE, GREEN),
)
text4 = MarkupText(
'fl ligature <gradient from="RED" to="YELLOW">causing trouble</gradient> here'
)
text5 = MarkupText(
'fl ligature <gradient from="RED" to="YELLOW" offset="1">defeated</gradient> with offset'
)
text6 = MarkupText(
'fl ligature <gradient from="RED" to="YELLOW" offset="1">floating</gradient> inside'
)
text7 = MarkupText(
'fl ligature <gradient from="RED" to="YELLOW" offset="1,1">floating</gradient> inside'
)
group = VGroup(text1, text2, text3, text4, text5, text6, text7).arrange(DOWN)
self.add(group)
.. manim:: UnderlineExample
:save_last_frame:
class UnderlineExample(Scene):
def construct(self):
text1 = MarkupText(
'<span underline="double" underline_color="green">bla</span>'
)
text2 = MarkupText(
'<span underline="single" underline_color="green">xxx</span><gradient from="#ffff00" to="RED">aabb</gradient>y'
)
text3 = MarkupText(
'<span underline="single" underline_color="green">xxx</span><gradient from="#ffff00" to="RED" offset="-1">aabb</gradient>y'
)
text4 = MarkupText(
'<span underline="double" underline_color="green">xxx</span><gradient from="#ffff00" to="RED">aabb</gradient>y'
)
text5 = MarkupText(
'<span underline="double" underline_color="green">xxx</span><gradient from="#ffff00" to="RED" offset="-2">aabb</gradient>y'
)
group = VGroup(text1, text2, text3, text4, text5).arrange(DOWN)
self.add(group)
.. manim:: FontExample
:save_last_frame:
class FontExample(Scene):
def construct(self):
text1 = MarkupText(
'all in sans <span font_family="serif">except this</span>', font="sans"
)
text2 = MarkupText(
'<span font_family="serif">mixing</span> <span font_family="sans">fonts</span> <span font_family="monospace">is ugly</span>'
)
text3 = MarkupText("special char > or >")
text4 = MarkupText("special char < and &")
group = VGroup(text1, text2, text3, text4).arrange(DOWN)
self.add(group)
.. manim:: NewlineExample
:save_last_frame:
class NewlineExample(Scene):
def construct(self):
text = MarkupText('foooo<span foreground="red">oo\nbaa</span>aar')
self.add(text)
.. manim:: NoLigaturesExample
:save_last_frame:
class NoLigaturesExample(Scene):
def construct(self):
text1 = MarkupText('fl<gradient from="RED" to="GREEN">oat</gradient>ing')
text2 = MarkupText('fl<gradient from="RED" to="GREEN">oat</gradient>ing', disable_ligatures=True)
group = VGroup(text1, text2).arrange(DOWN)
self.add(group)
As :class:`MarkupText` uses Pango to render text, rendering non-English
characters is easily possible:
.. manim:: MultiLanguage
:save_last_frame:
class MultiLanguage(Scene):
def construct(self):
morning = MarkupText("வணக்கம்", font="sans-serif")
japanese = MarkupText(
'<span fgcolor="blue">日本</span>へようこそ'
) # works as in ``Text``.
mess = MarkupText("Multi-Language", weight=BOLD)
russ = MarkupText("Здравствуйте मस नम म ", font="sans-serif")
hin = MarkupText("नमस्ते", font="sans-serif")
chinese = MarkupText("臂猿「黛比」帶著孩子", font="sans-serif")
group = VGroup(morning, japanese, mess, russ, hin, chinese).arrange(DOWN)
self.add(group)
You can justify the text by passing :attr:`justify` parameter.
.. manim:: JustifyText
class JustifyText(Scene):
def construct(self):
ipsum_text = (
"Lorem ipsum dolor sit amet, consectetur adipiscing elit."
"Praesent feugiat metus sit amet iaculis pulvinar. Nulla posuere "
"quam a ex aliquam, eleifend consectetur tellus viverra. Aliquam "
"fermentum interdum justo, nec rutrum elit pretium ac. Nam quis "
"leo pulvinar, dignissim est at, venenatis nisi."
)
justified_text = MarkupText(ipsum_text, justify=True).scale(0.4)
not_justified_text = MarkupText(ipsum_text, justify=False).scale(0.4)
just_title = Title("Justified")
njust_title = Title("Not Justified")
self.add(njust_title, not_justified_text)
self.play(
FadeOut(not_justified_text),
FadeIn(justified_text),
FadeOut(njust_title),
FadeIn(just_title),
)
self.wait(1)
Tests
-----
Check that the creation of :class:`~.MarkupText` works::
>>> MarkupText('The horse does not eat cucumber salad.')
MarkupText('The horse does not eat cucumber salad.')
"""
def __init__(
self,
text: str,
fill_opacity: float = 1,
stroke_width: float = 0,
color: ParsableManimColor | None = None,
font_size: float = DEFAULT_FONT_SIZE,
line_spacing: int = -1,
font: str = "",
slant: str = NORMAL,
weight: str = NORMAL,
justify: bool = False,
gradient: tuple = None,
tab_width: int = 4,
height: int = None,
width: int = None,
should_center: bool = True,
disable_ligatures: bool = False,
warn_missing_font: bool = True,
**kwargs,
) -> None:
self.text = text
self.line_spacing = line_spacing
if font and warn_missing_font:
fonts_list = manimpango.list_fonts()
if font not in fonts_list:
logger.warning(f"Font {font} not in {fonts_list}.")
self.font = font
self._font_size = float(font_size)
self.slant = slant
self.weight = weight
self.gradient = gradient
self.tab_width = tab_width
self.justify = justify
self.original_text = text
self.disable_ligatures = disable_ligatures
text_without_tabs = text
if "\t" in text:
text_without_tabs = text.replace("\t", " " * self.tab_width)
colormap = self._extract_color_tags()
if len(colormap) > 0:
logger.warning(
'Using <color> tags in MarkupText is deprecated. Please use <span foreground="..."> instead.',
)
gradientmap = self._extract_gradient_tags()
validate_error = MarkupUtils.validate(self.text)
if validate_error:
raise ValueError(validate_error)
if self.line_spacing == -1:
self.line_spacing = (
self._font_size + self._font_size * DEFAULT_LINE_SPACING_SCALE
)
else:
self.line_spacing = self._font_size + self._font_size * self.line_spacing
color: ManimColor = ManimColor(color) if color else VMobject().color
file_name = self._text2svg(color)
PangoUtils.remove_last_M(file_name)
super().__init__(
file_name,
fill_opacity=fill_opacity,
stroke_width=stroke_width,
height=height,
width=width,
should_center=should_center,
**kwargs,
)
self.chars = self.get_group_class()(*self.submobjects)
self.text = text_without_tabs.replace(" ", "").replace("\n", "")
nppc = self.n_points_per_curve
for each in self:
if len(each.points) == 0:
continue
points = each.points
curve_start = points[0]
assert len(curve_start) == self.dim, curve_start
# Some of the glyphs in this text might not be closed,
# so we close them by identifying when one curve ends
# but it is not where the next curve starts.
# It is more efficient to temporarily create a list
# of points and add them one at a time, then turn them
# into a numpy array at the end, rather than creating
# new numpy arrays every time a point or fixing line
# is added (which is O(n^2) for numpy arrays).
closed_curve_points = []
# OpenGL has points be part of quadratic Bezier curves;
# Cairo uses cubic Bezier curves.
if nppc == 3: # RendererType.OPENGL
def add_line_to(end):
nonlocal closed_curve_points
start = closed_curve_points[-1]
closed_curve_points += [
start,
(start + end) / 2,
end,
]
else: # RendererType.CAIRO
def add_line_to(end):
nonlocal closed_curve_points
start = closed_curve_points[-1]
closed_curve_points += [
start,
(start + start + end) / 3,
(start + end + end) / 3,
end,
]
for index, point in enumerate(points):
closed_curve_points.append(point)
if (
index != len(points) - 1
and (index + 1) % nppc == 0
and any(point != points[index + 1])
):
# Add straight line from last point on this curve to the
# start point on the next curve.
add_line_to(curve_start)
curve_start = points[index + 1]
# Make sure last curve is closed
add_line_to(curve_start)
each.points = np.array(closed_curve_points, ndmin=2)
if self.gradient:
self.set_color_by_gradient(*self.gradient)
for col in colormap:
self.chars[
col["start"]
- col["start_offset"] : col["end"]
- col["start_offset"]
- col["end_offset"]
].set_color(self._parse_color(col["color"]))
for grad in gradientmap:
self.chars[
grad["start"]
- grad["start_offset"] : grad["end"]
- grad["start_offset"]
- grad["end_offset"]
].set_color_by_gradient(
*(self._parse_color(grad["from"]), self._parse_color(grad["to"]))
)
# anti-aliasing
if height is None and width is None:
self.scale(TEXT_MOB_SCALE_FACTOR)
self.initial_height = self.height
@property
def font_size(self):
return (
self.height
/ self.initial_height
/ TEXT_MOB_SCALE_FACTOR
* 2.4
* self._font_size
/ DEFAULT_FONT_SIZE
)
@font_size.setter
def font_size(self, font_val):
# TODO: use pango's font size scaling.
if font_val <= 0:
raise ValueError("font_size must be greater than 0.")
else:
self.scale(font_val / self.font_size)
[docs] def _text2hash(self, color: ParsableManimColor):
"""Generates ``sha256`` hash for file name."""
settings = (
"MARKUPPANGO"
+ self.font
+ self.slant
+ self.weight
+ ManimColor(color).to_hex().lower()
) # to differentiate from classical Pango Text
settings += str(self.line_spacing) + str(self._font_size)
settings += str(self.disable_ligatures)
settings += str(self.justify)
id_str = self.text + settings
hasher = hashlib.sha256()
hasher.update(id_str.encode())
return hasher.hexdigest()[:16]
[docs] def _text2svg(self, color: ParsableManimColor | None):
"""Convert the text to SVG using Pango."""
color = ManimColor(color)
size = self._font_size
line_spacing = self.line_spacing
size /= TEXT2SVG_ADJUSTMENT_FACTOR
line_spacing /= TEXT2SVG_ADJUSTMENT_FACTOR
dir_name = config.get_dir("text_dir")
if not dir_name.is_dir():
dir_name.mkdir(parents=True)
hash_name = self._text2hash(color)
file_name = dir_name / (hash_name + ".svg")
if file_name.exists():
svg_file = str(file_name.resolve())
else:
final_text = (
f'<span foreground="{color.to_hex()}">{self.text}</span>'
if color is not None
else self.text
)
logger.debug(f"Setting Text {self.text}")
svg_file = MarkupUtils.text2svg(
final_text,
self.font,
self.slant,
self.weight,
size,
line_spacing,
self.disable_ligatures,
str(file_name.resolve()),
START_X,
START_Y,
600, # width
400, # height
justify=self.justify,
pango_width=500,
)
return svg_file
[docs] def _count_real_chars(self, s):
"""Counts characters that will be displayed.
This is needed for partial coloring or gradients, because space
counts to the text's `len`, but has no corresponding character."""
count = 0
level = 0
# temporarily replace HTML entities by single char
s = re.sub("&[^;]+;", "x", s)
for c in s:
if c == "<":
level += 1
if c == ">" and level > 0:
level -= 1
elif c != " " and c != "\t" and level == 0:
count += 1
return count
[docs] def _parse_color(self, col):
"""Parse color given in ``<color>`` or ``<gradient>`` tags."""
if re.match("#[0-9a-f]{6}", col):
return col
else:
return ManimColor(col).to_hex()
def __repr__(self):
return f"MarkupText({repr(self.original_text)})"
[docs]@contextmanager
def register_font(font_file: str | Path):
"""Temporarily add a font file to Pango's search path.
This searches for the font_file at various places. The order it searches it described below.
1. Absolute path.
2. In ``assets/fonts`` folder.
3. In ``font/`` folder.
4. In the same directory.
Parameters
----------
font_file
The font file to add.
Examples
--------
Use ``with register_font(...)`` to add a font file to search
path.
.. code-block:: python
with register_font("path/to/font_file.ttf"):
a = Text("Hello", font="Custom Font Name")
Raises
------
FileNotFoundError:
If the font doesn't exists.
AttributeError:
If this method is used on macOS.
.. important ::
This method is available for macOS for ``ManimPango>=v0.2.3``. Using this
method with previous releases will raise an :class:`AttributeError` on macOS.
"""
input_folder = Path(config.input_file).parent.resolve()
possible_paths = [
Path(font_file),
input_folder / "assets/fonts" / font_file,
input_folder / "fonts" / font_file,
input_folder / font_file,
]
for path in possible_paths:
path = path.resolve()
if path.exists():
file_path = path
logger.debug("Found file at %s", file_path.absolute())
break
else:
error = f"Can't find {font_file}." f"Tried these : {possible_paths}"
raise FileNotFoundError(error)
try:
assert manimpango.register_font(str(file_path))
yield
finally:
manimpango.unregister_font(str(file_path))