More customization

manimlib/__init__.py

@@ -2,11 +2,14 @@
 import manimlib.config
 import manimlib.constants
 import manimlib.extract_scene
+import manimlib.utils.tex_file_writing
 
 
 def main():
     args = manimlib.config.parse_cli()
     config = manimlib.config.get_configuration(args)
     manimlib.constants.initialize_directories(config)
     manimlib.constants.TEMPLATE_TEX_OBJ.configurate(config)
+    manimlib.constants.remember_presets(config)
+    manimlib.utils.tex_file_writing.clear_tex_cache(config)
     manimlib.extract_scene.main(config)

manimlib/animation/creation.py

@@ -23,7 +23,7 @@ def interpolate_submobject(self, submob, start_submob, alpha):
         )
 
     def get_bounds(self, alpha):
-        raise Exception("Not Implemented")
+        raise NotImplemented
 
 
 class ShowCreation(ShowPartial):

manimlib/config.py

@@ -15,6 +15,11 @@ def parse_cli():
             "file",
             help="path to file holding the python code for the scene",
         )
+        parser.add_argument(
+            "--presets",
+            default="manimlib/presets.conf",
+            help="File of configuration presets. manimlib/presets.conf by default."
+        )
         parser.add_argument(
             "scene_names",
             nargs="*",
@@ -149,6 +154,11 @@ def parse_cli():
             nargs="*",
             help="Names of XeLaTeX which will be located at the beginning of the .tex preamble."
         )
+        parser.add_argument(
+            "--clear-tex-cache",
+            action="store_true",
+            help="Recompile all .tex files before rendering."
+        )
         return parser.parse_args()
     except argparse.ArgumentError as err:
         print(str(err))
@@ -211,6 +221,8 @@ def get_configuration(args):
         "mono_font": args.mono_font,
         "pre_packages": args.pre_packages,
         "post_packages": args.post_packages,
+        "presets_file": args.presets,
+        "clear_tex_cache": args.clear_tex_cache
     }
 
     # Camera configuration

manimlib/constants.py

@@ -2,13 +2,16 @@
 import os
 
 from manimlib.utils.tex_preparing import TexFile
+import configparser
 
 MEDIA_DIR = ""
 VIDEO_DIR = ""
 VIDEO_OUTPUT_DIR = ""
 TEX_DIR = ""
 TEXT_DIR = ""
 
+PRESETS = configparser.ConfigParser()
+
 
 def initialize_directories(config):
     global MEDIA_DIR
@@ -54,6 +57,14 @@ def initialize_directories(config):
         if folder != "" and not os.path.exists(folder):
             os.makedirs(folder)
 
+def remember_presets(config):
+  global PRESETS
+  if not config["presets_file"]:
+    return
+
+  PRESETS.read_file(
+    open(config["presets_file"]))
+
 NOT_SETTING_FONT_MSG='''
 Warning:
 You haven't set font.

manimlib/mobject/coordinate_systems.py

@@ -8,15 +8,16 @@
 from manimlib.mobject.number_line import NumberLine
 from manimlib.mobject.svg.tex_mobject import TexMobject
 from manimlib.mobject.types.vectorized_mobject import VGroup
-from manimlib.utils.config_ops import digest_config
 from manimlib.utils.config_ops import merge_dicts_recursively
 from manimlib.utils.simple_functions import binary_search
 from manimlib.utils.space_ops import angle_of_vector
 
+from manimlib.utils.presetting import Presettable
+
 # TODO: There should be much more code reuse between Axes, NumberPlane and GraphScene
 
 
-class CoordinateSystem():
+class CoordinateSystem(Presettable):
     """
     Abstract class for Axes and NumberPlane
     """
@@ -29,10 +30,10 @@ class CoordinateSystem():
     }
 
     def coords_to_point(self, *coords):
-        raise Exception("Not implemented")
+        raise NotImplemented
 
     def point_to_coords(self, point):
-        raise Exception("Not implemented")
+        raise NotImplemented
 
     def c2p(self, *coords):
         """Abbreviation for coords_to_point"""
@@ -43,7 +44,7 @@ def p2c(self, point):
         return self.point_to_coords(point)
 
     def get_axes(self):
-        raise Exception("Not implemented")
+        raise NotImplemented
 
     def get_axis(self, index):
         return self.get_axes()[index]

manimlib/mobject/mobject.py

@@ -823,7 +823,7 @@ def get_start_and_end(self):
         return self.get_start(), self.get_end()
 
     def point_from_proportion(self, alpha):
-        raise Exception("Not implemented")
+        raise NotImplemented
 
     def get_pieces(self, n_pieces):
         template = self.copy()
@@ -1008,7 +1008,7 @@ def align_points(self, mobject):
         return self
 
     def align_points_with_larger(self, larger_mobject):
-        raise Exception("Not implemented")
+        raise NotImplemented
 
     def align_submobjects(self, mobject):
         mob1 = self

manimlib/mobject/svg/svg_mobject.py

@@ -402,7 +402,7 @@ def handle_command(self, command, coord_string):
             # TODO, this is a suboptimal approximation
             new_points = np.append([new_points[0]], new_points, axis=0)
         elif command == "A":  # elliptical Arc
-            raise Exception("Not implemented")
+            raise NotImplemented
         elif command == "Z":  # closepath
             return
 

manimlib/mobject/svg/tex_mobject.py

@@ -175,6 +175,12 @@ def break_up_by_substrings(self):
         deeper based on the structure of tex_strings (as a list
         of tex_strings)
         """
+        if not self.submobjects:
+            raise Exception(
+                f"TeX-compiled object \"{str(self.tex_string)}\" does not "
+                "contain any symbol. Consider using font compatible with your "
+                "language. Use -h option to get help on font parameters."
+            )
         new_submobjects = []
         curr_index = 0
         config = dict(self.CONFIG)

manimlib/mobject/types/image_mobject.py

@@ -21,7 +21,7 @@ class AbstractImageMobject(Mobject):
     }
 
     def get_pixel_array(self):
-        raise Exception("Not implemented")
+        raise NotImplemented
 
     def set_color(self):
         # Likely to be implemented in subclasses, but no obgligation

manimlib/once_useful_constructs/fractals.py

@@ -109,10 +109,10 @@ def get_order_n_self(self, order):
         return result
 
     def get_seed_shape(self):
-        raise Exception("Not implemented")
+        raise NotImplemented
 
     def arrange_subparts(self, *subparts):
-        raise Exception("Not implemented")
+        raise NotImplemented
 
 
 class Sierpinski(SelfSimilarFractal):
@@ -336,7 +336,7 @@ def init_colors(self):
                 self.set_stroke(width=self.order_to_stroke_width_map[order])
 
     def get_anchor_points(self):
-        raise Exception("Not implemented")
+        raise NotImplemented
 
 
 class LindenmayerCurve(FractalCurve):
@@ -421,7 +421,7 @@ def get_anchor_points(self):
         return points
 
     def generate_grid(self):
-        raise Exception("Not implemented")
+        raise NotImplemented
 
 
 class HilbertCurve(SelfSimilarSpaceFillingCurve):

manimlib/presets.conf

@@ -0,0 +1,18 @@
+# Use this file to make preset for every CONFIG of class that will be
+# instantiated.
+# Put the name of class into [brackets] and start setting properties in
+# key=value format (just search for config file formatting).
+# Nested parameters can be set by dot.
+
+# Specify type of your value as "option_name is const", "... is str",
+# "... is int" or "... is bool". Otherwise all values will be treated as string.
+# The example is given below.
+
+[NumberPlane]
+background_line_style.stroke_color is const = RED
+
+# Directives like that one can be easily used for styling your objects. Have a
+# look at class codes in manimlib/mobject to know the class' properties.
+
+[Mobject]
+color is const = BLUE_D

manimlib/utils/config_ops.py

@@ -71,9 +71,8 @@ def soft_dict_update(d1, d2):
     Adds key values pairs of d2 to d1 only when d1 doesn't
     already have that key
     """
-    for key, value in list(d2.items()):
-        if key not in d1:
-            d1[key] = value
+    for k, v in d2.items():
+        d1.setdefault(k, v)
 
 
 def digest_locals(obj, keys=None):

manimlib/utils/presetting.py

@@ -0,0 +1,68 @@
+import re
+
+from manimlib.constants import *
+
+
+class Presettable:
+    """Abstract class for classes which CONFIG may be preseted.
+    """
+    CONFIG = {}
+    CONFIGURATED = False
+
+    def __new__(cls, *args, **kwargs):
+        if not cls.CONFIGURATED:
+            assign_presets(cls)
+            cls.CONFIGURATED = True
+        return object.__new__(cls, *args, **kwargs)
+
+
+def change_by_dot(dictionary, key, value):
+    """Access the dict value by dot key and change it to `value` Example:
+    dot_access({"a":0},        "a",   ..) refers to d["a"]
+    dot_access({"a":{"b":0}}}, "a.b", ..) refers to d["a"]["b"]
+    """
+
+    def replacer(dict_slice, value, key_slice, *rest_slices):
+        # if current key_slice is the last, rest_slices evaluates to None
+        if not rest_slices:
+            dict_slice[key_slice] = value
+        else:
+            replacer(dict_slice[key_slice], value, *rest_slices)
+
+    # recursively dive into dict, and if key was found in current nested item,
+    # change its value
+    replacer(dictionary, value, *key.split("."))
+
+
+def assign_presets(obj):
+    """Sets CONFIG values of the UNINSTANTIATED class as given in presets file
+    in manimlib/presets.conf.
+    """
+
+    class_name = obj.__name__
+    if class_name not in PRESETS.sections():
+        return
+
+    # value parsers for different types should take two parameters:
+    # class name and option name and return the legit value for that property
+    value_parsers = {
+        "int": int,
+        "bool": lambda value: value.lower() in ["yes", "true", "1", "on"],
+        "str": str,
+        "const": lambda name: globals()[name]
+    }
+
+    for option in PRESETS.options(class_name):
+
+        if not option:
+            continue
+        # findall is guaranteed to match at least one symbol, so unpacking
+        # is safe.
+        prop_name, prop_type = re.findall(
+            r"([\w\d\.]+)(?: is (\w+))?",
+            option
+        )[0]
+        change_by_dot(
+            obj.CONFIG, prop_name,
+            value_parsers[prop_type or str](PRESETS.get(class_name, option))
+        )

manimlib/utils/tex_file_writing.py

@@ -5,6 +5,21 @@
 import manimlib.constants as consts
 
 
+def clear_tex_cache(config):
+    """Clear TEX_DIR path. May be useful in debugging or if you managed to
+    change .tex files there.
+    """
+
+    if not config["clear_tex_cache"]:
+        return
+
+    for fname in os.listdir(consts.TEX_DIR):
+        fpath = os.path.join(consts.TEX_DIR, fname)
+        # user will see OSError here in case of some problems
+        if os.path.isfile(fpath):
+            os.unlink(fpath)
+
+
 def tex_hash(expression, template_tex_file_body):
     id_str = str(expression + template_tex_file_body)
     hasher = hashlib.sha256()
@@ -32,6 +47,7 @@ def generate_tex_file(expression, template_tex_file_body):
             outfile.write(template_tex_file_body)
     return result
 
+
 def tex_to_dvi(tex_file):
     result = tex_file.replace(".tex", ".xdv")
     result = Path(result).as_posix()