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OrthogonalConnection

The class OrthogonalConnection creates a polyline that goes from p1 to p2, composed only by horizontal and vertical segments. The shape of the line is controlled by the path parameter.

There are two ways to use this class:

1. p1 and p2 are the start and end points of the line, and path is a string with the characters "-" and "|" indicating the horizontal and vertical segments of the line.

   For example "-|-" will start with a horizontal segment, that will go until the x coordinate intermediate between p1 and p2, then a vertical segment up to the y coordinate of p2, and finally a horizontal segment to p2.

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LatexTip

Manim provides few styles of arrow tips, basically a filled triangle and the "stealth".

This python module implements Latex-style arrow tips. The shape is a perfect copy of the one used by Computer Modern fonts. It was produced by exporting to svg a latex document containing $\to$, and editing the resulting SVG using Inkscape to remove the arrow stem and leave only the tip. This SVG was read into manim to extract the array of points used to define this class.

This is an example of several arrows with several kinds of tips pointing in all directions (the code is the file example.py in this gist.

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How animations work (more or less)

To be frank, I don't know all the details about making your own custom Animation class. I know only a general idea, but the details are fuzzy. I usually end up using a trial-and-error approach trying different methods and reading the source code of similar animations, until it works. But the main idea is:

1. An animation receives a mobject (it can be a group) on which it will operate. In the __init__ method usually it only stores that object into self.mobject, so every animation has that object, and other animation attributes such as the run time, rate function, etc.
2. When used in a .play(), manim will call its begin() method. Usually you don't need to override that. The default implementation creates another inner object called self.starting_mobject which stores the initial state of the mobject being animated, and it is simply a deep copy of self.mobject (although you can override how that starting mobject is created by overriding `create_starting_mobj

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Code utilities

The module code_utils.py contains functions useful to deal with code.

Currently it only contains find_in_code() function, described below

find_in_code(code, string, lines)

Finds all occurrences of the string string in the code object code, optionally restricting the search to the lines specified in the lines

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	Transform(a,b)	ReplacementTransform(a,b)	TransformFromCopy(a,b)
a initial shape	a	a	a
a final shape	b	b	a (never changed)
b initial shape	b	b	a (temporarly)
b final shape	b (never changed)	b (never changed)	b
In scene during transform	a (morphing into b)	a (morphing into b)	b (morphing from a's shape)
In scene after transform	a (in the shape of b)	b	b

See illustrative video here -> https://gist.github.com/assets/44573666/71b711f1-88ab-4065-8aa9-a8c333ffaa29

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Landscape barchart for manim

Example code

from manim import *
from landscapebarchart import LandscapeBarChart

# Note that the y axis in this landscape bar chart will be horizontal, and the x_axis will be vertical
# Also when the documentation/code refers to bar heights, it will be actually the rectangle width,