Ported improved implementation of :class:.SVGMobject from 3b1b/manim (#2898)

* port SVGMobject from 3b1b/manim

* added svgelements as dependency

* revert change of default values

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* set default stroke_width of svg elements to 0 if not set

* fix handling of circles with different rx/ry

* turn more methods into staticmethods

* removed duplicated method

* set/adapt stroke-width of some test SVGs

* updated control data

* forgot some control data

* fixed init_colors in tex_mobject and text_mobject

* minor changes, added docstrings

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* module docstring, removed import

* vector_to_coords changed again

* nail sphinx version to below 5.1 to fix rtd (?)

* update test_text control data for science

* changed Brace to use VMobjectFromSVGPath

* remove unused classes and methods depending on old SVG path implementation

* remove style_utils and svg_path modules

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* change test_text to use monospace font

* restore geometry.polygram

* added get_mobject_type_class auxiliary method; changed polyline implementation to ad-hoc approach

* restore test_text to previous version

* skip Use tags as svgelements already populates them

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: behackl

docs/requirements.txt

@@ -1,5 +1,5 @@
 furo
 myst-parser
-sphinx
+sphinx<5.1
 sphinx-copybutton
 sphinxext-opengraph

manim/mobject/mobject.py

@@ -2135,6 +2135,11 @@ def __len__(self):
     def get_group_class(self):
         return Group
 
+    @staticmethod
+    def get_mobject_type_class():
+        """Return the base class of this mobject type."""
+        return Mobject
+
     def split(self):
         result = [self] if len(self.points) > 0 else []
         return result + self.submobjects

manim/mobject/opengl/opengl_mobject.py

@@ -2281,6 +2281,11 @@ def align_to(
     def get_group_class(self):
         return OpenGLGroup
 
+    @staticmethod
+    def get_mobject_type_class():
+        """Return the base class of this mobject type."""
+        return OpenGLMobject
+
     # Alignment
 
     def align_data_and_family(self, mobject):

manim/mobject/opengl/opengl_point_cloud_mobject.py

@@ -155,6 +155,10 @@ def get_shader_data(self):
         self.read_data_to_shader(shader_data, "color", "rgbas")
         return shader_data
 
+    @staticmethod
+    def get_mobject_type_class():
+        return OpenGLPMobject
+
 
 class OpenGLPGroup(OpenGLPMobject):
     def __init__(self, *pmobs, **kwargs):

manim/mobject/opengl/opengl_vectorized_mobject.py

@@ -142,6 +142,10 @@ def __init__(
     def get_group_class(self):
         return OpenGLVGroup
 
+    @staticmethod
+    def get_mobject_type_class():
+        return OpenGLVMobject
+
     def init_data(self):
         super().init_data()
         self.data.pop("rgbas")
@@ -389,10 +393,18 @@ def get_colors(self):
     fill_color = property(get_fill_color, set_fill)
 
     def has_stroke(self):
-        return any(self.get_stroke_widths()) and any(self.get_stroke_opacities())
+        stroke_widths = self.get_stroke_widths()
+        stroke_opacities = self.get_stroke_opacities()
+        return (
+            stroke_widths is not None
+            and stroke_opacities is not None
+            and any(stroke_widths)
+            and any(stroke_opacities)
+        )
 
     def has_fill(self):
-        return any(self.get_fill_opacities())
+        fill_opacities = self.get_fill_opacities()
+        return fill_opacities is not None and any(fill_opacities)
 
     def get_opacity(self):
         if self.has_fill():

manim/mobject/svg/__init__.py

@@ -7,7 +7,5 @@
     :toctree: ../reference
 
     ~brace
-    ~style_utils
     ~svg_mobject
-    ~svg_path
 """

manim/mobject/svg/brace.py

@@ -7,6 +7,7 @@
 from typing import Sequence
 
 import numpy as np
+import svgelements as se
 
 from manim._config import config
 from manim.mobject.geometry.arc import Arc
@@ -18,12 +19,12 @@
 from ...animation.fading import FadeIn
 from ...animation.growing import GrowFromCenter
 from ...constants import *
-from ...mobject.svg.svg_path import SVGPathMobject
 from ...mobject.types.vectorized_mobject import VMobject
 from ...utils.color import BLACK
+from ..svg.svg_mobject import VMobjectFromSVGPath
 
 
-class Brace(SVGPathMobject):
+class Brace(VMobjectFromSVGPath):
     """Takes a mobject and draws a brace adjacent to it.
 
     Passing a direction vector determines the direction from which the
@@ -99,19 +100,22 @@ def __init__(
             (target_width * sharpness - default_min_width) / 2,
         )
 
-        path = path_string_template.format(
-            linear_section_length,
-            -linear_section_length,
+        path = se.Path(
+            path_string_template.format(
+                linear_section_length,
+                -linear_section_length,
+            )
         )
 
         super().__init__(
-            path_string=path,
+            path_obj=path,
             stroke_width=stroke_width,
             fill_opacity=fill_opacity,
             background_stroke_width=background_stroke_width,
             background_stroke_color=background_stroke_color,
             **kwargs,
         )
+        self.flip(RIGHT)
         self.stretch_to_fit_width(target_width)
         self.shift(left - self.get_corner(UP + LEFT) + self.buff * DOWN)