Adding "label_buff" config parameter for Brace

[TurkeyBilly]

Motivation

-When adding a Brace Label, I can adjust the label scale and the buff between the brace and the mobject adding to. However, I can not adjust the buff between the label and the brace, which would make the distance disproportional.

-Directly using brace.scale() does not work either, as this will change the length of the brace as well.

-Meanwhile, directly passing in the argument buff=value as keyword argument will set the buff between the target mobject and the brace only. And since both methods (Brace.CONFIG and Brace.put_at_tip) use the buff keyword argument, therefore, to allow different values can be passed in for "mobject-brace buff" and "brace-label buff", this parameter is clarified as label_buff.

brace1 = BraceLabel(dl1, 'r', UP, label_scale=0.35, font_size=30, buff=0.1)

For example, the code above will result in

Which in this case the small 'r' is clearly too far away from the brace.

Proposed changes

• In file manimlib.mobject.svg.brace.py, class BraceLable, added parameter label_buff in the CONFIG
• In Line 108, pass in the parameter buff=self.label_buff for put_at_top method
• Added import copy at the beginning

Test

Code:

brace1 = BraceLabel(dl1, 'r', UP, label_scale=0.35, font_size=30, buff=0.1, label_buff=0.1)

Result:

In addition, the previous version was missing an importation
before

after