Refactor Text

manimlib/mobject/svg/text_mobject.py

@@ -1,4 +1,3 @@
-import itertools as it
 import os
 import re
 import typing
@@ -10,12 +9,13 @@ import pygments
 import pygments.formatters
 import pygments.lexers
 
-import manimglpango
+import manimpango
+from manimpango import MarkupUtils
 from manimlib.logger import log
 from manimlib.constants import *
 from manimlib.mobject.geometry import Dot
 from manimlib.mobject.svg.svg_mobject import SVGMobject
-from manimlib.utils.iterables import adjacent_pairs
+from manimlib.utils.customization import get_customization
 from manimlib.utils.tex_file_writing import tex_hash
 from manimlib.utils.config_ops import digest_config
 from manimlib.utils.directories import get_downloads_dir
@@ -26,49 +26,228 @@ TEXT_MOB_SCALE_FACTOR = 0.0076
 DEFAULT_LINE_SPACING_SCALE = 0.6
 
 
+class _TextParser(object):
+    # See https://docs.gtk.org/Pango/pango_markup.html
+    # A tag containing two aliases will cause warning,
+    # so only use the first key of each group of aliases.
+    SPAN_ATTR_KEY_ALIAS_LIST = (
+        ("font", "font_desc"),
+        ("font_family", "face"),
+        ("font_size", "size"),
+        ("font_style", "style"),
+        ("font_weight", "weight"),
+        ("font_variant", "variant"),
+        ("font_stretch", "stretch"),
+        ("font_features",),
+        ("foreground", "fgcolor", "color"),
+        ("background", "bgcolor"),
+        ("alpha", "fgalpha"),
+        ("background_alpha", "bgalpha"),
+        ("underline", "underline_color"),
+        ("overline", "overline_color"),
+        ("rise",),
+        ("baseline_shift",),
+        ("font_scale",),
+        ("strikethrough",),
+        ("strikethrough_color",),
+        ("fallback",),
+        ("lang",),
+        ("letter_spacing",),
+        ("gravity",),
+        ("gravity_hint",),
+        ("show",),
+        ("insert_hyphens",),
+        ("allow_breaks",),
+        ("line_height",),
+        ("text_transform",),
+        ("segment",),
+    )
+    SPAN_ATTR_KEY_CONVERSION = {
+        key: key_alias_list[0]
+        for key_alias_list in SPAN_ATTR_KEY_ALIAS_LIST
+        for key in key_alias_list
+    }
+    SPAN_ATTR_KEY_ALIASES = tuple(SPAN_ATTR_KEY_CONVERSION.keys())
+
+    TAG_TO_ATTR_DICT = {
+        "b": {"font_weight": "bold"},
+        "big": {"font_size": "larger"},
+        "i": {"font_style": "italic"},
+        "s": {"strikethrough": "true"},
+        "sub": {"baseline_shift": "subscript", "font_scale": "subscript"},
+        "sup": {"baseline_shift": "superscript", "font_scale": "superscript"},
+        "small": {"font_size": "smaller"},
+        "tt": {"font_family": "monospace"},
+        "u": {"underline": "single"},
+    }
+
+    def __init__(self, text: str = "", is_markup: bool = True):
+        self.text = text
+        self.is_markup = is_markup
+        self.global_attrs = {}
+        self.local_attrs = {(0, len(self.text)): {}}
+        self.tag_strings = set()
+        if is_markup:
+            self.parse_markup()
+
+    def parse_markup(self) -> None:
+        tag_pattern = r"""<(/?)(\w+)\s*((\w+\s*\=\s*('[^']*'|"[^"]*")\s*)*)>"""
+        attr_pattern = r"""(\w+)\s*\=\s*(?:(?:'([^']*)')|(?:"([^"]*)"))"""
+        start_match_obj_stack = []
+        match_obj_pairs = []
+        for match_obj in re.finditer(tag_pattern, self.text):
+            if not match_obj.group(1):
+                start_match_obj_stack.append(match_obj)
+            else:
+                match_obj_pairs.append((start_match_obj_stack.pop(), match_obj))
+            self.tag_strings.add(match_obj.group())
+        assert not start_match_obj_stack, "Unclosed tag(s) detected"
+
+        for start_match_obj, end_match_obj in match_obj_pairs:
+            tag_name = start_match_obj.group(2)
+            assert tag_name == end_match_obj.group(2), "Unmatched tag names"
+            assert not end_match_obj.group(3), "Attributes shan't exist in ending tags"
+            if tag_name == "span":
+                attr_dict = {
+                    match.group(1): match.group(2) or match.group(3)
+                    for match in re.finditer(attr_pattern, start_match_obj.group(3))
+                }
+            elif tag_name in _TextParser.TAG_TO_ATTR_DICT.keys():
+                assert not start_match_obj.group(3), f"Attributes shan't exist in tag '{tag_name}'"
+                attr_dict = _TextParser.TAG_TO_ATTR_DICT[tag_name]
+            else:
+                raise AssertionError(f"Unknown tag: '{tag_name}'")
+
+            text_span = (start_match_obj.end(), end_match_obj.start())
+            self.update_local_attrs(text_span, attr_dict)
+
+    @staticmethod
+    def convert_key_alias(key: str) -> str:
+        return _TextParser.SPAN_ATTR_KEY_CONVERSION[key]
+
+    @staticmethod
+    def update_attr_dict(attr_dict: dict[str, str], key: str, value: str) -> None:
+        converted_key = _TextParser.convert_key_alias(key)
+        attr_dict[converted_key] = value
+
+    def update_global_attr(self, key: str, value: str) -> None:
+        _TextParser.update_attr_dict(self.global_attrs, key, value)
+
+    def update_global_attrs(self, attr_dict: dict[str, str]) -> None:
+        for key, value in attr_dict.items():
+            self.update_global_attr(key, value)
+
+    def update_local_attr(self, span: tuple[int, int], key: str, value: str) -> None:
+        if span[0] >= span[1]:
+            log.warning(f"Span {span} doesn't match any part of the string")
+            return
+
+        if span in self.local_attrs.keys():
+            _TextParser.update_attr_dict(self.local_attrs[span], key, value)
+            return
+
+        span_triplets = []
+        for sp, attr_dict in self.local_attrs.items():
+            if sp[1] <= span[0] or span[1] <= sp[0]:
+                continue
+            span_to_become = (max(sp[0], span[0]), min(sp[1], span[1]))
+            spans_to_add = []
+            if sp[0] < span[0]:
+                spans_to_add.append((sp[0], span[0]))
+            if span[1] < sp[1]:
+                spans_to_add.append((span[1], sp[1]))
+            span_triplets.append((sp, span_to_become, spans_to_add))
+        for span_to_remove, span_to_become, spans_to_add in span_triplets:
+            attr_dict = self.local_attrs.pop(span_to_remove)
+            for span_to_add in spans_to_add:
+                self.local_attrs[span_to_add] = attr_dict.copy()
+            self.local_attrs[span_to_become] = attr_dict
+            _TextParser.update_attr_dict(self.local_attrs[span_to_become], key, value)
+
+    def update_local_attrs(self, text_span: tuple[int, int], attr_dict: dict[str, str]) -> None:
+        for key, value in attr_dict.items():
+            self.update_local_attr(text_span, key, value)
+
+    def get_string_content(self, string: str) -> str:
+        for tag_string in self.tag_strings:
+            string = string.replace(tag_string, "")
+        if not self.is_markup:
+            string = saxutils.escape(string)
+        return string
+
+    def get_text_pieces(self) -> list[tuple[str, dict[str, str]]]:
+        result = []
+        for span in sorted(self.local_attrs.keys()):
+            text_piece = self.get_string_content(self.text[slice(*span)])
+            if not text_piece:
+                continue
+            attr_dict = self.global_attrs.copy()
+            attr_dict.update(self.local_attrs[span])
+            result.append((text_piece, attr_dict))
+        return result
+
+    def get_markup_str_with_attrs(self):
+        return "".join([
+            f"<span {_TextParser.get_attr_dict_str(attr_dict)}>{text_piece}</span>"
+            for text_piece, attr_dict in self.get_text_pieces()
+        ])
+
+    @staticmethod
+    def get_attr_dict_str(attr_dict: dict[str, str]):
+        return " ".join([
+            f"{key}='{value}'"
+            for key, value in attr_dict.items()
+        ])
+
+
+# Temporary handler
+class _Alignment:
+    VAL_LIST = ["LEFT", "CENTER", "RIGHT"]
+    def __init__(self, s):
+        self.value = _Alignment.VAL_LIST.index(s.upper())
+
+
 class Text(SVGMobject):
     CONFIG = {
         # Mobject
+        "stroke_width": 0,
         "svg_default": {
             "color": WHITE,
-            "opacity": 1.0,
-            "stroke_width": 0,
         },
         "height": None,
         # Text
+        "is_markup": False,
         "font_size": 48,
         "lsh": None,
         "justify": False,
         "indent": 0,
         "alignment": "LEFT",
-        "line_width": -1,  # No auto wrapping if set to -1
+        "line_width_factor": None,  # No auto wrapping if set to None
         "font": "",
-        "gradient": None,
         "slant": NORMAL,
         "weight": NORMAL,
+        "gradient": None,
         "t2c": {},
         "t2f": {},
         "t2g": {},
         "t2s": {},
         "t2w": {},
         "disable_ligatures": True,
-        "escape_chars": True,
         "apply_space_chars": True,
     }
 
     def __init__(self, text, **kwargs):
         self.full2short(kwargs)
         digest_config(self, kwargs)
-        validate_error = manimglpango.validate(text)
+        validate_error = MarkupUtils.validate(text)
         if validate_error:
             raise ValueError(validate_error)
         self.text = text
-        super.__init__(**kwargs)
+        self.parser = _TextParser(text, is_markup=self.is_markup)
+        super().__init__(**kwargs)
 
-        self.scale(self.font_size / 48)  # TODO
         if self.gradient:
             self.set_color_by_gradient(*self.gradient)
-        # anti-aliasing
         if self.height is None:
             self.scale(TEXT_MOB_SCALE_FACTOR)
 
@@ -79,12 +258,13 @@ class Text(SVGMobject):
             self.svg_default,
             self.path_string_config,
             self.text,
-            #self.font_size,
+            self.is_markup,
+            self.font_size,
             self.lsh,
             self.justify,
             self.indent,
             self.alignment,
-            self.line_width,
+            self.line_width_factor,
             self.font,
             self.slant,
             self.weight,
@@ -93,7 +273,6 @@ class Text(SVGMobject):
             self.t2s,
             self.t2w,
             self.disable_ligatures,
-            self.escape_chars,
             self.apply_space_chars
         )
 
@@ -113,49 +292,36 @@ class Text(SVGMobject):
                 "Please set gradient via `set_color_by_gradient`.",
             )
 
-        global_params = {}
-        lsh = self.lsh or DEFAULT_LINE_SPACING_SCALE
-        global_params["line_height"] = 0.6 * lsh + 0.64
-        if self.font:
-            global_params["font_family"] = self.font
-        #global_params["font_size"] = self.font_size * 1024
-        global_params["font_style"] = self.slant
-        global_params["font_weight"] = self.weight
-        if self.disable_ligatures:
-            global_params["font_features"] = "liga=0,dlig=0,clig=0,hlig=0"
-        text_span_to_params_map = {
-            (0, len(self.text)): global_params
+        config_style_dict = self.generate_config_style_dict()
+        global_attr_dict = {
+            "line_height": str(((self.lsh or DEFAULT_LINE_SPACING_SCALE) + 1) * 0.6),
+            "font_family": self.font or get_customization()["style"]["font"],
+            "font_size": str(self.font_size * 1024),
+            "font_style": self.slant,
+            "font_weight": self.weight,
+            # TODO, it seems this doesn't work
+            "font_features": "liga=0,dlig=0,clig=0,hlig=0" if self.disable_ligatures else None,
+            "foreground": config_style_dict.get("fill", None),
+            "alpha": config_style_dict.get("fill-opacity", None)
         }
+        global_attr_dict = {
+            k: v
+            for k, v in global_attr_dict.items()
+            if v is not None
+        }
+        self.parser.update_global_attrs(global_attr_dict)
 
         for t2x_dict, key in (
-            (self.t2c, "color"),
+            (self.t2c, "foreground"),
             (self.t2f, "font_family"),
             (self.t2s, "font_style"),
             (self.t2w, "font_weight")
         ):
             for word_or_text_span, value in t2x_dict.items():
                 for text_span in self.find_indexes(word_or_text_span):
-                    if text_span not in text_span_to_params_map:
-                        text_span_to_params_map[text_span] = {}
-                    text_span_to_params_map[text_span][key] = value
+                    self.parser.update_local_attr(text_span, key, str(value))
 
-        indices, _, flags, param_dicts = zip(*sorted([
-            (*text_span[::(1, -1)[flag]], flag, param_dict)
-            for text_span, param_dict in text_span_to_params_map.items()
-            for flag in range(2)
-        ]))
-        tag_pieces = [
-            (f"<span {self.get_attr_list_str(param_dict)}>", "</span>")[flag]
-            for flag, param_dict in zip(flags, param_dicts)
-        ]
-        tag_pieces.insert(0, "")
-        string_pieces = [
-            self.text[slice(*piece_span)]
-            for piece_span in list(adjacent_pairs(indices))[:-1]
-        ]
-        if self.escape_chars:
-            string_pieces = list(map(saxutils.escape, string_pieces))
-        return "".join(it.chain(*zip(tag_pieces, string_pieces)))
+        return self.parser.get_markup_str_with_attrs()
 
     def find_indexes(self, word_or_text_span):
         if isinstance(word_or_text_span, tuple):
@@ -166,30 +332,33 @@ class Text(SVGMobject):
             for match_obj in re.finditer(re.escape(word_or_text_span), self.text)
         ]
 
-    @staticmethod
-    def get_attr_list_str(param_dict):
-        return " ".join([
-            f"{key}='{value}'"
-            for key, value in param_dict.items()
-        ])
-
     def markup_to_svg(self, markup_str, file_name):
-        width = DEFAULT_PIXEL_WIDTH
-        height = DEFAULT_PIXEL_HEIGHT
-        justify = self.justify
-        indent = self.indent
-        alignment = ["LEFT", "CENTER", "RIGHT"].index(self.alignment.upper())
-        line_width = self.line_width * 1024
+        # `manimpango` is under construction,
+        # so the following code is intended to suit its interface
+        alignment = _Alignment(self.alignment)
+        if self.line_width_factor is None:
+            pango_width = -1
+        else:
+            pango_width = self.line_width_factor * DEFAULT_PIXEL_WIDTH
 
-        return manimglpango.markup_to_svg(
-            markup_str,
-            file_name,
-            width,
-            height,
-            justify=justify,
-            indent=indent,
+        return MarkupUtils.text2svg(
+            text=markup_str,
+            font="",                     # Already handled
+            slant="NORMAL",              # Already handled
+            weight="NORMAL",             # Already handled
+            size=1,                      # Already handled
+            _=0,                         # Empty parameter
+            disable_liga=False,          # Already handled
+            file_name=file_name,
+            START_X=0,
+            START_Y=0,
+            width=DEFAULT_PIXEL_WIDTH,
+            height=DEFAULT_PIXEL_HEIGHT,
+            justify=self.justify,
+            indent=self.indent,
+            line_spacing=None,           # Already handled
             alignment=alignment,
-            line_width=line_width
+            pango_width=pango_width
         )
 
     def generate_mobject(self):
@@ -198,9 +367,10 @@ class Text(SVGMobject):
         # Remove empty paths
         submobjects = list(filter(lambda submob: submob.has_points(), self))
 
-        # Apply space characters
+        # Apply space characters (may be deprecated?)
         if self.apply_space_chars:
-            for char_index, char in enumerate(self.text):
+            content_str = self.parser.get_string_content(self.text)
+            for char_index, char in enumerate(content_str):
                 if not re.match(r"\s", char):
                     continue
                 space = Dot(radius=0, fill_opacity=0, stroke_opacity=0)
@@ -225,19 +395,20 @@ class Text(SVGMobject):
 
 class MarkupText(Text):
     CONFIG = {
-        "escape_chars": False,
+        "is_markup": True,
         "apply_space_chars": False,
     }
 
 
-class Code(Text):
+class Code(MarkupText):
     CONFIG = {
         "font": "Consolas",
         "font_size": 24,
-        "lsh": 1.0,  # TODO
+        "lsh": 1.0,
         "language": "python",
         # Visit https://pygments.org/demo/ to have a preview of more styles.
-        "code_style": "monokai"
+        "code_style": "monokai",
+        "apply_space_chars": True
     }
 
     def __init__(self, code, **kwargs):
@@ -245,8 +416,10 @@ class Code(Text):
         self.code = code
         lexer = pygments.lexers.get_lexer_by_name(self.language)
         formatter = pygments.formatters.PangoMarkupFormatter(style=self.code_style)
-        markup_code = pygments.highlight(code, lexer, formatter)
-        super().__init__(markup_code, **kwargs)
+        markup = pygments.highlight(code, lexer, formatter)
+        markup = markup.replace("<tt>", f"<span font_family='{self.font}'>")
+        markup = markup.replace("</tt>", "</span>")
+        super().__init__(markup, **kwargs)
 
 
 @contextmanager
@@ -296,7 +469,7 @@ def register_font(font_file: typing.Union[str, Path]):
         raise FileNotFoundError(error)
 
     try:
-        assert manimglpango.register_font(str(file_path))
+        assert manimpango.register_font(str(file_path))
         yield
     finally:
-        manimglpango.unregister_font(str(file_path))
+        manimpango.unregister_font(str(file_path))

requirements.txt

@@ -17,6 +17,6 @@ screeninfo
 validators
 ipython
 PyOpenGL
-manimpango>=0.2.0,<0.4.0
+manimpango>=0.4.0.post0,<0.5.0
 isosurfaces
 svgelements

setup.cfg

@@ -49,7 +49,7 @@ install_requires =
     validators
     ipython
     PyOpenGL
-    manimpango>=0.2.0,<0.4.0
+    manimpango>=0.4.0.post0,<0.5.0
     isosurfaces
     svgelements