kivy/doc/sources/guide/environment.rst

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.. _environment:
Controlling the environment
===========================
Many environment variables are available to control the initialization and
behavior of Kivy.
For example, in order to restrict text rendering to the PIL implementation::
$ KIVY_TEXT=pil python main.py
Environment variables should be set before importing kivy::
import os
os.environ['KIVY_TEXT'] = 'pil'
import kivy
Path control
------------
.. versionadded:: 1.0.7
You can control the default directories where config files, modules
and kivy data are located.
KIVY_DATA_DIR
Location of the Kivy data, defaults to `<kivy path>/data`
KIVY_MODULES_DIR
Location of the Kivy modules, defaults to `<kivy path>/modules`
KIVY_HOME
Location of the Kivy home. This directory is used for local configuration,
and must be in a writable location.
Defaults to:
- Desktop: `<user home>/.kivy`
- Android: `<android app path>/.kivy`
- iOS: `<user home>/Documents/.kivy`
.. versionadded:: 1.9.0
KIVY_SDL2_PATH
If set, the SDL2 libraries and headers from this path are used when
compiling kivy instead of the ones installed system-wide.
To use the same libraries while running a kivy app, this path must be
added at the start of the PATH environment variable.
.. versionadded:: 1.9.0
.. warning::
This path is required for the compilation of Kivy. It is not
required for program execution.
Configuration
-------------
KIVY_USE_DEFAULTCONFIG
If this name is found in environ, Kivy will not read the user config file.
KIVY_NO_CONFIG
If set, no configuration file will be read or written to. This also applies
to the user configuration directory.
KIVY_NO_FILELOG
If set, logs will be not print to a file
KIVY_NO_CONSOLELOG
If set, logs will be not print to the console
KIVY_NO_ARGS
If set to one of ('true', '1', 'yes'), the argument passed in command line
will not be parsed and used by Kivy. Ie, you can safely make a script or an
app with your own arguments without requiring the `--` delimiter::
import os
os.environ["KIVY_NO_ARGS"] = "1"
import kivy
.. versionadded:: 1.9.0
KCFG_section_key
If a such format environment name is detected, it will be mapped
to the Config object. They are loaded only once when `kivy` is
imported. The behavior can be disabled using `KIVY_NO_ENV_CONFIG`.
::
import os
os.environ["KCFG_KIVY_LOG_LEVEL"] = "warning"
import kivy
# during import it will map it to:
# Config.set("kivy", "log_level", "warning")
.. versionadded:: 1.11.0
KIVY_NO_ENV_CONFIG
If set, no environment key will be mapped to configuration object.
If unset, any `KCFG_section_key=value` will be mapped to Config.
.. versionadded:: 1.11.0
Restrict core to specific implementation
----------------------------------------
:mod:`kivy.core` try to select the best implementation available for your
platform. For testing or custom installation, you might want to restrict the
selector to a specific implementation.
KIVY_WINDOW
Implementation to use for creating the Window
Values: sdl2, pygame, x11, egl_rpi
KIVY_TEXT
Implementation to use for rendering text
Values: sdl2, pil, pygame, sdlttf
KIVY_VIDEO
Implementation to use for rendering video
Values: gstplayer, ffpyplayer, ffmpeg, null
KIVY_AUDIO
Implementation to use for playing audio
Values: sdl2, gstplayer, ffpyplayer, pygame, avplayer
KIVY_IMAGE
Implementation to use for reading image
Values: sdl2, pil, pygame, imageio, tex, dds, gif
KIVY_CAMERA
Implementation to use for reading camera
Values: avfoundation, android, opencv
KIVY_SPELLING
Implementation to use for spelling
Values: enchant, osxappkit
KIVY_CLIPBOARD
Implementation to use for clipboard management
Values: sdl2, pygame, dummy, android
Metrics
-------
KIVY_DPI
If set, the value will be used for :attr:`Metrics.dpi`.
.. versionadded:: 1.4.0
KIVY_METRICS_DENSITY
If set, the value will be used for :attr:`Metrics.density`.
.. versionadded:: 1.5.0
KIVY_METRICS_FONTSCALE
If set, the value will be used for :attr:`Metrics.fontscale`.
.. versionadded:: 1.5.0
Graphics
--------
KIVY_GL_BACKEND
The OpenGL backend to use. See :mod:`~kivy.graphics.cgl`.
KIVY_GL_DEBUG
Whether to log OpenGL calls. See :mod:`~kivy.graphics.cgl`.
KIVY_GRAPHICS
Whether to use OpenGL ES2. See :mod:`~kivy.graphics.cgl`.
KIVY_GLES_LIMITS
Whether the GLES2 restrictions are enforced (the default, or if set to
1). If set to false, Kivy will not be truly GLES2 compatible.
Following is a list of the potential incompatibilities that result
when set to true.
============== ====================================================
Mesh indices If true, the number of indices in a mesh is limited
to 65535
Texture blit When blitting to a texture, the data (color and
buffer) format must be the same format as the one
used at the texture creation. On desktop, the
conversion of different color is correctly handled
by the driver, while on Android, most of devices
fail to do it.
Ref: https://github.com/kivy/kivy/issues/1600
============== ====================================================
.. versionadded:: 1.8.1
KIVY_BCM_DISPMANX_ID
Change the default Raspberry Pi display to use. The list of available value
is accessible in `vc_dispmanx_types.h`. Default value is 0:
- 0: DISPMANX_ID_MAIN_LCD
- 1: DISPMANX_ID_AUX_LCD
- 2: DISPMANX_ID_HDMI
- 3: DISPMANX_ID_SDTV
- 4: DISPMANX_ID_FORCE_LCD
- 5: DISPMANX_ID_FORCE_TV
- 6: DISPMANX_ID_FORCE_OTHER
KIVY_BCM_DISPMANX_LAYER
Change the default Raspberry Pi dispmanx layer. Default value is 0.
.. versionadded:: 1.10.1
Event Loop
----------
KIVY_EVENTLOOP
Which async library should be used when the app is run in an asynchronous
manner. See :mod:`kivy.app` for example usage.
``'asyncio'``: When the app is run in an asynchronous manner and the standard
library asyncio package should be used. The default if not set.
``'trio'``: When the app is run in an asynchronous manner and the `trio`
package should be used.
.. versionadded:: 2.0.0