Improved ImageFont documentation

This commit is contained in:
Andrew Murray 2019-07-07 20:52:30 +10:00
parent ea50ac5760
commit dfed1424d1
2 changed files with 29 additions and 84 deletions

View File

@ -47,90 +47,11 @@ Functions
Methods Methods
------- -------
.. py:method:: PIL.ImageFont.ImageFont.getsize(text, direction=None, features=[], language=None) .. autoclass:: PIL.ImageFont.ImageFont
:members:
Returns width and height (in pixels) of given text if rendered in font with
provided direction, features, and language.
:param text: Text to measure.
:param direction: Direction of the text. It can be 'rtl' (right to
left), 'ltr' (left to right) or 'ttb' (top to bottom).
Requires libraqm.
.. versionadded:: 4.2.0
:param features: A list of OpenType font features to be used during text
layout. This is usually used to turn on optional
font features that are not enabled by default,
for example 'dlig' or 'ss01', but can be also
used to turn off default font features for
example '-liga' to disable ligatures or '-kern'
to disable kerning. To get all supported
features, see
https://docs.microsoft.com/en-us/typography/opentype/spec/featurelist
Requires libraqm.
.. versionadded:: 4.2.0
:param language: Language of the text. Different languages may use
different glyph shapes or ligatures. This parameter tells
the font which language the text is in, and to apply the
correct substitutions as appropriate, if available.
It should be a `BCP 47 language code
<https://www.w3.org/International/articles/language-tags/>`
Requires libraqm.
.. versionadded:: 6.0.0
:return: (width, height)
.. py:method:: PIL.ImageFont.ImageFont.getmask(text, mode='', direction=None, features=[], language=None)
Create a bitmap for the text.
If the font uses antialiasing, the bitmap should have mode “L” and use a
maximum value of 255. Otherwise, it should have mode “1”.
:param text: Text to render.
:param mode: Used by some graphics drivers to indicate what mode the
driver prefers; if empty, the renderer may return either
mode. Note that the mode is always a string, to simplify
C-level implementations.
.. versionadded:: 1.1.5
:param direction: Direction of the text. It can be 'rtl' (right to
left), 'ltr' (left to right) or 'ttb' (top to bottom).
Requires libraqm.
.. versionadded:: 4.2.0
:param features: A list of OpenType font features to be used during text
layout. This is usually used to turn on optional
font features that are not enabled by default,
for example 'dlig' or 'ss01', but can be also
used to turn off default font features for
example '-liga' to disable ligatures or '-kern'
to disable kerning. To get all supported
features, see
https://docs.microsoft.com/en-us/typography/opentype/spec/featurelist
Requires libraqm.
.. versionadded:: 4.2.0
:param language: Language of the text. Different languages may use
different glyph shapes or ligatures. This parameter tells
the font which language the text is in, and to apply the
correct substitutions as appropriate, if available.
It should be a `BCP 47 language code
<https://www.w3.org/International/articles/language-tags/>`
Requires libraqm.
.. versionadded:: 6.0.0
:return: An internal PIL storage memory instance as defined by the
:py:mod:`PIL.Image.core` interface module.
.. autoclass:: PIL.ImageFont.FreeTypeFont .. autoclass:: PIL.ImageFont.FreeTypeFont
:members: :members:
.. autoclass:: PIL.ImageFont.TransposedFont
:members:

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@ -110,9 +110,33 @@ class ImageFont(object):
self.font = Image.core.font(image.im, data) self.font = Image.core.font(image.im, data)
def getsize(self, text, *args, **kwargs): def getsize(self, text, *args, **kwargs):
"""
Returns width and height (in pixels) of given text.
:param text: Text to measure.
:return: (width, height)
"""
return self.font.getsize(text) return self.font.getsize(text)
def getmask(self, text, mode="", *args, **kwargs): def getmask(self, text, mode="", *args, **kwargs):
"""
Create a bitmap for the text.
If the font uses antialiasing, the bitmap should have mode ``L`` and use a
maximum value of 255. Otherwise, it should have mode ``1``.
:param text: Text to render.
:param mode: Used by some graphics drivers to indicate what mode the
driver prefers; if empty, the renderer may return either
mode. Note that the mode is always a string, to simplify
C-level implementations.
.. versionadded:: 1.1.5
:return: An internal PIL storage memory instance as defined by the
:py:mod:`PIL.Image.core` interface module.
"""
return self.font.getmask(text, mode) return self.font.getmask(text, mode)