add what's new doc

Alain · Alain · commit 41b7a2088f18 · 2023-05-25T17:44:45.000+08:00
diff --git a/doc/users/next_whats_new/antialiasing_text_annotation.rst b/doc/users/next_whats_new/antialiasing_text_annotation.rst
@@ -0,0 +1,40 @@
+Support customizing antialiasing for text and annotation
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+``matplotlib.pyplot.annotate()`` and ``matplotlib.pyplot.text()`` now support parameter ``antialiased``.
+When ``antialiased`` is set to ``True``, antialiasing will be applied to the text.
+When ``antialiased`` is set to ``False``, antialiasing will not be applied to the text.
+When ``antialiased`` is not specified, antialiasing will be set by ``rcParams['text.antialiased']`` at the creation time of ``Text`` and ``Annotation`` object.
+
+Examples:
+
+.. code-block::
+
+    mpl.text.Text(.5, .5, "foo\nbar", antialiased=True)
+    plt.text(0.5, 0.5, '6 inches x 2 inches', antialiased=True)
+    ax.annotate('local max', xy=(2, 1), xytext=(3, 1.5), antialiased=False)
+
+If the text contains math expression, then anaialiasing will be set by ``rcParams['text.antialiased']``, and ``antialiased`` will have no effect
+This applies to the whole text.
+Examples:
+
+.. code-block::
+
+    # no part will be antialiased for the text below
+    plt.text(0.5, 0.25, r"$I'm \sqrt{x}$", antialiased=False)
+
+Also note that antialiasing for tick labeles will be set with ``rcParams['text.antialiased']`` when they are created (usually when a ``Figure`` is created) and cannot be changed afterwards.
+
+Furthermore, with this new feature, you may want to make sure that you are creating and saving/showing the figure under the same context::
+
+    # previously this was a no-op, now it is what works
+    with rccontext(text.antialiased=False):
+        fig, ax = plt.subplots()
+        ax.annotate('local max', xy=(2, 1), xytext=(3, 1.5))
+        fig.savefig('/tmp/test.png')
+
+
+    # previously this had an effect, now this is a no-op
+    fig, ax = plt.subplots()
+    ax.annotate('local max', xy=(2, 1), xytext=(3, 1.5))
+    with rccontext(text.antialiased=False):
+        fig.savefig('/tmp/test.png')
