常量部分constants

声明

这一页翻译+笔记自EulerTour写的教程,整合elteoremadebeethoven写的 manim_3feb_docs

还有鹤翔万里在manim_sandbox中编写的wiki中的内容

编辑manimlib/constants.py相关定义即可。 manimlib 文件夹中的 constants.py 定义了在运行manim时需要的常量。 一些常量在这里没有说明，因为他们只在manim内部使用

配置目录

MEDIA_DIR

文件夹 VIDEO_DIR 和 TEX_DIR 创建的位置（如果他们没有被选项更改的话）

VIDEO_DIR

存放manim渲染结果视频的文件夹，当一个场景渲染结束，它会存放在 VIDEO_DIR/<module_name>/<scene_name>/<quality>/<scene_name>.mp4. 默认根据 MEDIA_DIR 创建

TEX_DIR

使用LaTeX创建的文件（tex/svg/log/xdv/aux），会作为缓存，来防止多次重写LaTeX

TEXT_DIR

使用 Text 类时，通过cairo创建的文字的svg，会作为缓存

这些文件夹如果不存在会被创建

当你第一次运行一个动画时，你会看到下面的信息:

Media will be stored in media/. You can change this behavior by writing a different directory to media_dir.txt.

这是因为动画文件会被保存到 media 文件夹中，在manim文件夹中，你会自动生成一个文件夹和两个文件：

.
├── manim/imports.py
├── manim.py
├── stage_scenes.py
├── media              # <- New directory
├── media_dir.txt      # <- New file
└── manimlib
    └── media_dir.txt  # <- New file

更改目录的方法很多，可以新建文件media_dir.txt在这里设置视频保存路径，可以是绝对路径：C:\manim\media。 也可以在 constants.py 文件中配置。

在manimlib/constants.py中定义了一些常用的常量，如下

定义的渲染画质

PRODUCTION_QUALITY_CAMERA_CONFIG = { # -w的画质
    "pixel_height": 1440,
    "pixel_width": 2560,
    "frame_rate": 60,
}

HIGH_QUALITY_CAMERA_CONFIG = { # --high_quality的画质
    "pixel_height": 1080,
    "pixel_width": 1920,
    "frame_rate": 60,
}

MEDIUM_QUALITY_CAMERA_CONFIG = { # -m的画质
    "pixel_height": 720,
    "pixel_width": 1280,
    "frame_rate": 30,
}

LOW_QUALITY_CAMERA_CONFIG = { # -l的画质
    "pixel_height": 480,
    "pixel_width": 854,
    "frame_rate": 15,
}

# 默认画质
DEFAULT_PIXEL_HEIGHT = PRODUCTION_QUALITY_CAMERA_CONFIG["pixel_height"]
DEFAULT_PIXEL_WIDTH = PRODUCTION_QUALITY_CAMERA_CONFIG["pixel_width"]
DEFAULT_FRAME_RATE = 60

点密度，线宽度

DEFAULT_POINT_DENSITY_2D = 25
DEFAULT_POINT_DENSITY_1D = 250

DEFAULT_STROKE_WIDTH = 4

画面上坐标的宽高

FRAME_HEIGHT = 8.0  # 画面高默认8个单位
FRAME_WIDTH = FRAME_HEIGHT * DEFAULT_PIXEL_WIDTH / DEFAULT_PIXEL_HEIGHT
FRAME_Y_RADIUS = FRAME_HEIGHT / 2
FRAME_X_RADIUS = FRAME_WIDTH / 2

buff

SMALL_BUFF = 0.1
MED_SMALL_BUFF = 0.25
MED_LARGE_BUFF = 0.5
LARGE_BUFF = 1

DEFAULT_MOBJECT_TO_EDGE_BUFFER = MED_LARGE_BUFF # 物体和边的距离
DEFAULT_MOBJECT_TO_MOBJECT_BUFFER = MED_SMALL_BUFF # 物体之间的距离

播放时间

DEFAULT_POINTWISE_FUNCTION_RUN_TIME = 3.0
DEFAULT_WAIT_TIME = 1.0

位置坐标

manim使用三维坐标，并且用 ndarray 的类型

ORIGIN = np.array((0., 0., 0.))
UP = np.array((0., 1., 0.))
DOWN = np.array((0., -1., 0.))
RIGHT = np.array((1., 0., 0.))
LEFT = np.array((-1., 0., 0.))
IN = np.array((0., 0., -1.))
OUT = np.array((0., 0., 1.))
X_AXIS = np.array((1., 0., 0.))
Y_AXIS = np.array((0., 1., 0.))
Z_AXIS = np.array((0., 0., 1.))

# Useful abbreviations for diagonals
UL = UP + LEFT
UR = UP + RIGHT
DL = DOWN + LEFT
DR = DOWN + RIGHT

TOP = FRAME_Y_RADIUS * UP
BOTTOM = FRAME_Y_RADIUS * DOWN
LEFT_SIDE = FRAME_X_RADIUS * LEFT
RIGHT_SIDE = FRAME_X_RADIUS * RIGHT

数学常数

PI = np.pi
TAU = 2 * PI
DEGREES = TAU / 360

颜色

这里是manim中定义的颜色的预览：(修改自 elteoremadebeethoven)

BLUE

BLUE_E

BLUE_D

BLUE_C

BLUE_B

BLUE_A

TEAL

TEAL_E

TEAL_D

TEAL_C

TEAL_B

TEAL_A

GREEN

GREEN_E

GREEN_D

GREEN_C

GREEN_B

GREEN_A

YELLOW

YELLOW_E

YELLOW_D

YELLOW_C

YELLOW_B

YELLOW_A

GOLD

GOLD_E

GOLD_D

GOLD_C

GOLD_B

GOLD_A

RED

RED_E

RED_D

RED_C

RED_B

RED_A

MAROON

MAROON_E

MAROON_D

MAROON_C

MAROON_B

MAROON_A

PURPLE

PURPLE_E

PURPLE_D

PURPLE_C

PURPLE_B

PURPLE_A

Others

WHITE

BLACK

LIGHT_GREY

LIGHT_GRAY

GREY

GRAY

DARK_GREY

DARK_GRAY

DARKER_GREY

DARKER_GRAY

GREY_BROWN

DARK_BROWN

LIGHT_BROWN

DARK_BLUE

PINK

LIGHT_PINK

GREEN_SCREEN

ORANGE

另外，在pycharm编辑器中颜色会警告，可以调小警告等级。 在vscode中如果你安装了python扩展也会发出警告，其原因是vscode在检测变量时并不会识别在运行时添加的变量， 所以需要将COLOR_MAP中的颜色提取出来作为常量令vscode识别。你需要注释这两行代码：

# for name in [s for s in list(COLOR_MAP.keys()) if s.endswith("_C")]:
#     locals()[name.replace("_C", "")] = locals()[name]

并将下方代码复制在constants.py中：

DARK_BLUE = "#236B8E"
DARK_BROWN = "#8B4513"
LIGHT_BROWN = "#CD853F"
BLUE_E = "#1C758A"
BLUE_D = "#29ABCA"
BLUE_C = "#58C4DD"
BLUE_B = "#9CDCEB"
BLUE_A = "#C7E9F1"
TEAL_E = "#49A88F"
TEAL_D = "#55C1A7"
TEAL_C = "#5CD0B3"
TEAL_B = "#76DDC0"
TEAL_A = "#ACEAD7"
GREEN_E = "#699C52"
GREEN_D = "#77B05D"
GREEN_C = "#83C167"
GREEN_B = "#A6CF8C"
GREEN_A = "#C9E2AE"
YELLOW_E = "#E8C11C"
YELLOW_D = "#F4D345"
YELLOW_C = "#FFFF00"
YELLOW_B = "#FFEA94"
YELLOW_A = "#FFF1B6"
GOLD_E = "#C78D46"
GOLD_D = "#E1A158"
GOLD_C = "#F0AC5F"
GOLD_B = "#F9B775"
GOLD_A = "#F7C797"
RED_E = "#CF5044"
RED_D = "#E65A4C"
RED_C = "#FC6255"
RED_B = "#FF8080"
RED_A = "#F7A1A3"
MAROON_E = "#94424F"
MAROON_D = "#A24D61"
MAROON_C = "#C55F73"
MAROON_B = "#EC92AB"
MAROON_A = "#ECABC1"
PURPLE_E = "#644172"
PURPLE_D = "#715582"
PURPLE_C = "#9A72AC"
PURPLE_B = "#B189C6"
PURPLE_A = "#CAA3E8"
WHITE = "#FFFFFF"
BLACK = "#000000"
LIGHT_GRAY = "#BBBBBB"
LIGHT_GREY = "#BBBBBB"
GRAY = "#888888"
GREY = "#888888"
DARK_GREY = "#444444"
DARK_GRAY = "#444444"
DARKER_GREY = "#222222"
DARKER_GRAY = "#222222"
GREY_BROWN = "#736357"
PINK = "#D147BD"
LIGHT_PINK = "#DC75CD"
GREEN_SCREEN = "#00FF00"
ORANGE = "#FF862F"
BLUE = "#58C4DD"
TEAL = "#5CD0B3"
GREEN = "#83C167"
YELLOW = "#FFFF00"
GOLD = "#F0AC5F"
RED = "#FC6255"
MAROON = "#C55F73"
PURPLE = "#9A72AC"