Add ImageText (#9098)

Author: mergify[bot]

Tests/test_imagetext.py

@@ -0,0 +1,72 @@
+from __future__ import annotations
+
+import pytest
+
+from PIL import Image, ImageDraw, ImageFont, ImageText
+
+from .helper import assert_image_similar_tofile, skip_unless_feature
+
+FONT_PATH = "Tests/fonts/FreeMono.ttf"
+
+
+@pytest.fixture(
+    scope="module",
+    params=[
+        pytest.param(ImageFont.Layout.BASIC),
+        pytest.param(ImageFont.Layout.RAQM, marks=skip_unless_feature("raqm")),
+    ],
+)
+def layout_engine(request: pytest.FixtureRequest) -> ImageFont.Layout:
+    return request.param
+
+
+@pytest.fixture(scope="module")
+def font(layout_engine: ImageFont.Layout) -> ImageFont.FreeTypeFont:
+    return ImageFont.truetype(FONT_PATH, 20, layout_engine=layout_engine)
+
+
+def test_get_length(font: ImageFont.FreeTypeFont) -> None:
+    assert ImageText.Text("A", font).get_length() == 12
+    assert ImageText.Text("AB", font).get_length() == 24
+    assert ImageText.Text("M", font).get_length() == 12
+    assert ImageText.Text("y", font).get_length() == 12
+    assert ImageText.Text("a", font).get_length() == 12
+
+
+def test_get_bbox(font: ImageFont.FreeTypeFont) -> None:
+    assert ImageText.Text("A", font).get_bbox() == (0, 4, 12, 16)
+    assert ImageText.Text("AB", font).get_bbox() == (0, 4, 24, 16)
+    assert ImageText.Text("M", font).get_bbox() == (0, 4, 12, 16)
+    assert ImageText.Text("y", font).get_bbox() == (0, 7, 12, 20)
+    assert ImageText.Text("a", font).get_bbox() == (0, 7, 12, 16)
+
+
+def test_standard_embedded_color(layout_engine: ImageFont.Layout) -> None:
+    font = ImageFont.truetype(FONT_PATH, 40, layout_engine=layout_engine)
+    text = ImageText.Text("Hello World!", font)
+    text.embed_color()
+
+    im = Image.new("RGB", (300, 64), "white")
+    draw = ImageDraw.Draw(im)
+    draw.text((10, 10), text, "#fa6")
+
+    assert_image_similar_tofile(im, "Tests/images/standard_embedded.png", 3.1)
+
+
+@skip_unless_feature("freetype2")
+def test_stroke() -> None:
+    for suffix, stroke_fill in {"same": None, "different": "#0f0"}.items():
+        # Arrange
+        im = Image.new("RGB", (120, 130))
+        draw = ImageDraw.Draw(im)
+        font = ImageFont.truetype(FONT_PATH, 120)
+        text = ImageText.Text("A", font)
+        text.stroke(2, stroke_fill)
+
+        # Act
+        draw.text((12, 12), text, "#f00")
+
+        # Assert
+        assert_image_similar_tofile(
+            im, "Tests/images/imagedraw_stroke_" + suffix + ".png", 3.1
+        )

docs/reference/ImageDraw.rst

@@ -582,6 +582,8 @@ Methods
         hello_world = hello + world  # kerning is disabled, no need to adjust
         assert hello_world == draw.textlength("HelloWorld", font, features=["-kern"])  # True
 
+    .. seealso:: :py:meth:`PIL.ImageText.Text.get_length`
+
     .. versionadded:: 8.0.0
 
     :param text: Text to be measured. May not contain any newline characters.
@@ -683,6 +685,8 @@ Methods
     1/64 pixel precision. The bounding box includes extra margins for
     some fonts, e.g. italics or accents.
 
+    .. seealso:: :py:meth:`PIL.ImageText.Text.get_bbox`
+
     .. versionadded:: 8.0.0
 
     :param xy: The anchor coordinates of the text.

docs/reference/ImageText.rst

@@ -0,0 +1,61 @@
+.. py:module:: PIL.ImageText
+.. py:currentmodule:: PIL.ImageText
+
+:py:mod:`~PIL.ImageText` module
+===============================
+
+The :py:mod:`~PIL.ImageText` module defines a :py:class:`~PIL.ImageText.Text` class.
+Instances of this class provide a way to use fonts with text strings or bytes. The
+result is a simple API to apply styling to pieces of text and measure or draw them.
+
+Example
+-------
+
+::
+
+    from PIL import Image, ImageDraw, ImageFont, ImageText
+    font = ImageFont.truetype("Tests/fonts/FreeMono.ttf", 24)
+
+    text = ImageText.Text("Hello world", font)
+    text.embed_color()
+    text.stroke(2, "#0f0")
+
+    print(text.get_length())  # 154.0
+    print(text.get_bbox())  # (-2, 3, 156, 22)
+
+    im = Image.new("RGB", text.get_bbox()[2:])
+    d = ImageDraw.Draw(im)
+    d.text((0, 0), text, "#f00")
+
+Comparison
+----------
+
+Without ``ImageText.Text``::
+
+  from PIL import Image, ImageDraw
+  im = Image.new(mode, size)
+  d = ImageDraw.Draw(im)
+
+  d.textlength(text, font, direction, features, language, embedded_color)
+  d.multiline_textbbox(xy, text, font, anchor, spacing, align, direction, features, language, stroke_width, embedded_color)
+  d.text(xy, text, fill, font, anchor, spacing, align, direction, features, language, stroke_width, stroke_fill, embedded_color)
+
+With ``ImageText.Text``::
+
+  from PIL import ImageText
+  text = ImageText.Text(text, font, mode, spacing, direction, features, language)
+  text.embed_color()
+  text.stroke(stroke_width, stroke_fill)
+
+  text.get_length()
+  text.get_bbox(xy, anchor, align)
+
+  im = Image.new(mode, size)
+  d = ImageDraw.Draw(im)
+  d.text(xy, text, fill, anchor=anchor, align=align)
+
+Methods
+-------
+
+.. autoclass:: PIL.ImageText.Text
+    :members:

docs/reference/index.rst

@@ -24,6 +24,7 @@ Reference
    ImageSequence
    ImageShow
    ImageStat
+   ImageText
    ImageTk
    ImageTransform
    ImageWin

docs/releasenotes/12.0.0.rst

@@ -124,6 +124,39 @@ Image.alpha_composite: LA images
 
 :py:meth:`~PIL.Image.alpha_composite` can now use LA images as well as RGBA.
 
+API additions
+=============
+
+Added ImageText.Text
+^^^^^^^^^^^^^^^^^^^^
+
+:py:class:`PIL.ImageText.Text` has been added, as a simpler way to use fonts with text
+strings or bytes.
+
+Without ``ImageText.Text``::
+
+  from PIL import Image, ImageDraw
+  im = Image.new(mode, size)
+  d = ImageDraw.Draw(im)
+
+  d.textlength(text, font, direction, features, language, embedded_color)
+  d.multiline_textbbox(xy, text, font, anchor, spacing, align, direction, features, language, stroke_width, embedded_color)
+  d.text(xy, text, fill, font, anchor, spacing, align, direction, features, language, stroke_width, stroke_fill, embedded_color)
+
+With ``ImageText.Text``::
+
+  from PIL import ImageText
+  text = ImageText.Text(text, font, mode, spacing, direction, features, language)
+  text.embed_color()
+  text.stroke(stroke_width, stroke_fill)
+
+  text.get_length()
+  text.get_bbox(xy, anchor, align)
+
+  im = Image.new(mode, size)
+  d = ImageDraw.Draw(im)
+  d.text(xy, text, fill, anchor=anchor, align=align)
+
 Other changes
 =============