Merge pull request matplotlib#22008 from oscargus/math_to_image_color_support

Added color keyword argument to math_to_image

Author: QuLogic

doc/users/next_whats_new/color_support_for_math_to_image.rst

@@ -0,0 +1,11 @@
+``math_to_image`` now has a *color* keyword argument
+--------------------------------------------------------
+
+To easily support external libraries that rely on the MathText rendering of
+Matplotlib to generate equation images, a *color* keyword argument was added
+to `~matplotlib.mathtext.math_to_image`.
+
+.. code-block:: python
+
+    from matplotlib import mathtext
+    mathtext.math_to_image('$x^2$', 'filename.png', color='Maroon')

lib/matplotlib/mathtext.py

@@ -563,7 +563,8 @@ def get_depth(self, texstr, dpi=120, fontsize=14):
         return depth
 
 
-def math_to_image(s, filename_or_obj, prop=None, dpi=None, format=None):
+def math_to_image(s, filename_or_obj, prop=None, dpi=None, format=None,
+                  *, color=None):
     """
     Given a math expression, renders it in a closely-clipped bounding
     box to an image file.
@@ -582,14 +583,16 @@ def math_to_image(s, filename_or_obj, prop=None, dpi=None, format=None):
     format : str, optional
         The output format, e.g., 'svg', 'pdf', 'ps' or 'png'.  If not set, the
         format is determined as for `.Figure.savefig`.
+    color : str, optional
+        Foreground color, defaults to :rc:`text.color`.
     """
     from matplotlib import figure
 
     parser = MathTextParser('path')
     width, height, depth, _, _ = parser.parse(s, dpi=72, prop=prop)
 
     fig = figure.Figure(figsize=(width / 72.0, height / 72.0))
-    fig.text(0, depth/height, s, fontproperties=prop)
+    fig.text(0, depth/height, s, fontproperties=prop, color=color)
     fig.savefig(filename_or_obj, dpi=dpi, format=format)
 
     return depth

lib/matplotlib/tests/test_mathtext.py

@@ -373,6 +373,7 @@ def test_mathtext_fallback(fallback, fontlist):
 def test_math_to_image(tmpdir):
     mathtext.math_to_image('$x^2$', str(tmpdir.join('example.png')))
     mathtext.math_to_image('$x^2$', io.BytesIO())
+    mathtext.math_to_image('$x^2$', io.BytesIO(), color='Maroon')
 
 
 def test_mathtext_to_png(tmpdir):