matplotlib · Abitamim · Dec 16, 2022 · Dec 16, 2022 · Dec 16, 2022 · Dec 16, 2022
diff --git a/lib/matplotlib/patches.py b/lib/matplotlib/patches.py
@@ -2372,14 +2372,35 @@ def __call__(self, x0, y0, width, height, mutation_size):
     class LArrow:
         """A box in the shape of a left-pointing arrow."""
 
-        def __init__(self, pad=0.3):
+        def __init__(self, pad=0.3, head_width=1.5, head_angle=90.0):
             """
             Parameters
             ----------
             pad : float, default: 0.3
                 The amount of padding around the original box.
+            head_width : float, default: 1.5
+                The width of the arrow head versus the body. The minimum value
+                is 0.0 and the maximum value is 10.0. Any value smaller or
+                greater than this is contrained to the edge values.
+            head_angle : float, default: 90.0
+                The inside angle of the tip of the arrow. The minimum value is
+                10.0 and the maximum value is 179.0. Any value smaller or
+                greater than this is contrained to the edge values.
             """
             self.pad = pad
+            if head_width > 10:
+                self.head_width = 10
+            elif head_width < 0:
+                self.head_width = 0
+            else:
+                self.head_width = head_width
+
+            if head_angle >= 180:
+                self.head_angle = 179
+            elif head_angle < 10:
+                self.head_angle = 10
+            else:
+                self.head_angle = head_angle
 
         def __call__(self, x0, y0, width, height, mutation_size):
             # padding
@@ -2394,10 +2415,26 @@ def __call__(self, x0, y0, width, height, mutation_size):
             dxx = dx / 2
             x0 = x0 + pad / 1.4  # adjust by ~sqrt(2)
 
+            # The width adjustment is the value that must be added or
+            # subtracted from y_0 and y_1 for the ends of the head.
+            # The body width is 2dx.
+            # Subtracting 1 from the head_width gives what percentage of the
+            # body width is in the head, and there is .5x of that on each side.
+            # The .5 cancels out the 2dx for the body width.
+            width_adjustment = (self.head_width - 1) * dx
+
+            # The angle adjustment is the value that must be subtracted/added
+            # from x_0 or x_1 for the position of the tip.
+            # each half of the arrow head is a right angle triangle. Therefore,
+            # each half of the arrow head has the equation tan(head_angle/2)=
+            # (dx+width_adjustment)/(dxx+angle_adjustment).
+            angle_adjustment = ((dx + width_adjustment) / math.tan((self.
+                                head_angle/2) * (math.pi/180))) - dxx
+
             return Path._create_closed(
                 [(x0 + dxx, y0), (x1, y0), (x1, y1), (x0 + dxx, y1),
-                 (x0 + dxx, y1 + dxx), (x0 - dx, y0 + dx),
-                 (x0 + dxx, y0 - dxx),  # arrow
+                 (x0 + dxx, y1 + width_adjustment), (x0 - angle_adjustment, y0
+                 + dx), (x0 + dxx, y0 - width_adjustment),  # arrow
                  (x0 + dxx, y0)])
 
     @_register_style(_style_list)
@@ -2415,14 +2452,35 @@ class DArrow:
         """A box in the shape of a two-way arrow."""
         # Modified from LArrow to add a right arrow to the bbox.
 
-        def __init__(self, pad=0.3):
+        def __init__(self, pad=0.3, head_width=1.5, head_angle=90.0):
             """
             Parameters
             ----------
             pad : float, default: 0.3
                 The amount of padding around the original box.
+            head_width : float, default: 1.5
+                The width of the arrow head versus the body. The minimum value
+                is 0.0 and the maximum value is 10.0. Any value smaller or
+                greater than this is contrained to the edge values.
+            head_angle : float, default: 90.0
+                The inside angle of the tip of the arrow. The minimum value is
+                10.0 and the maximum value is 179.0. Any value smaller or
+                greater than this is contrained to the edge values.
             """
             self.pad = pad
+            if head_width > 10:
+                self.head_width = 10
+            elif head_width < 0:
+                self.head_width = 0
+            else:
+                self.head_width = head_width
+
+            if head_angle >= 180:
+                self.head_angle = 179
+            elif head_angle < 10:
+                self.head_angle = 10
+            else:
+                self.head_angle = head_angle
 
         def __call__(self, x0, y0, width, height, mutation_size):
             # padding
@@ -2438,13 +2496,31 @@ def __call__(self, x0, y0, width, height, mutation_size):
             dxx = dx / 2
             x0 = x0 + pad / 1.4  # adjust by ~sqrt(2)
 
+            # The width adjustment is the value that must be added or
+            # subtracted from y_0 and y_1 for the ends of the head.
+            # The body width is 2dx.
+            # Subtracting 1 from the head_width gives what percentage of the
+            # body width is in the head, and there is .5x of that on each side.
+            # The .5 cancels out the 2dx for the body width.
+            width_adjustment = (self.head_width - 1) * dx
+
+            # The angle adjustment is the value that must be subtracted/added
+            # from x_0 or x_1 for the position of the tip.
+            # each half of the arrow head is a right angle triangle. Therefore,
+            # each half of the arrow head has the equation tan(head_angle/2)=
+            # (dx+width_adjustment)/(dxx+angle_adjustment).
+            angle_adjustment = ((dx + width_adjustment) / math.tan((self.
+                                head_angle/2) * (math.pi/180))) - dxx
+
             return Path._create_closed([
                 (x0 + dxx, y0), (x1, y0),  # bot-segment
-                (x1, y0 - dxx), (x1 + dx + dxx, y0 + dx),
-                (x1, y1 + dxx),  # right-arrow
+                (x1, y0 - width_adjustment),
+                (x1 + angle_adjustment + dxx, y0 + dx),
+                (x1, y1 + width_adjustment),  # right-arrow
                 (x1, y1), (x0 + dxx, y1),  # top-segment
-                (x0 + dxx, y1 + dxx), (x0 - dx, y0 + dx),
-                (x0 + dxx, y0 - dxx),  # left-arrow
+                (x0 + dxx, y1 + width_adjustment),
+                (x0 - angle_adjustment, y0 + dx),
+                (x0 + dxx, y0 - width_adjustment),  # left-arrow
                 (x0 + dxx, y0)])
 
     @_register_style(_style_list)

diff --git a/lib/matplotlib/tests/baseline_images/test_arrow_patches/roadsign_test_image.png b/lib/matplotlib/tests/baseline_images/test_arrow_patches/roadsign_test_image.png
diff --git a/lib/matplotlib/tests/test_arrow_patches.py b/lib/matplotlib/tests/test_arrow_patches.py
@@ -48,6 +48,29 @@ def test_boxarrow():
                  bbox=dict(boxstyle=stylename, fc="w", ec="k"))
 
 
+@image_comparison(['roadsign_test_image.png'])
+def temp_test_boxarrow():
+
+    styles = mpatches.BoxStyle.get_styles()
+
+    n = len(styles)
+    spacing = 1.2
+
+    figheight = (n * spacing + .5)
+    fig = plt.figure(figsize=(4 / 1.5, figheight / 1.5))
+
+    fontsize = 0.3 * 72
+
+    for i, stylename in enumerate(sorted(styles)):
+        if stylename in ("larrow", "rarrow", "darrow"):
+            fig.text(0.5, ((n - i) * spacing - 0.5)/figheight, stylename,
+                        ha="center",
+                        size=fontsize,
+                        transform=fig.transFigure,
+                        bbox=dict(boxstyle=stylename+",head_width=1", fc="w",
+                                    ec="k"))
+
+
 def __prepare_fancyarrow_dpi_cor_test():
     """
     Convenience function that prepares and returns a FancyArrowPatch. It aims

diff --git a/tutorials/text/annotations.py b/tutorials/text/annotations.py
@@ -192,10 +192,10 @@
 #   Class        Name             Attrs
 #   ==========   ==============   ==========================
 #   Circle       ``circle``       pad=0.3
-#   DArrow       ``darrow``       pad=0.3
+#   DArrow       ``darrow``       pad=0.3,head_width=1.5,head_angle=90
 #   Ellipse      ``ellipse``      pad=0.3
-#   LArrow       ``larrow``       pad=0.3
-#   RArrow       ``rarrow``       pad=0.3
+#   LArrow       ``larrow``       pad=0.3,head_width=1.5,head_angle=90
+#   RArrow       ``rarrow``       pad=0.3,head_width=1.5,head_angle=90
 #   Round        ``round``        pad=0.3,rounding_size=None
 #   Round4       ``round4``       pad=0.3,rounding_size=None
 #   Roundtooth   ``roundtooth``   pad=0.3,tooth_size=None
@@ -254,8 +254,8 @@ def custom_box_style(x0, y0, width, height, mutation_size):
     x0, y0 = x0 - pad, y0 - pad
     x1, y1 = x0 + width, y0 + height
     # return the new path
-    return Path([(x0, y0), (x1, y0), (x1, y1), (x0, y1),
-                 (x0-pad, (y0+y1)/2), (x0, y0), (x0, y0)],
+    return Path([(x0, y0), (x1, y0), (x1, y1), (x0, y1), (x0, y1-pad),
+                 (x0-pad, (y0+y1)/2), (x0, y0+pad), (x0, y0), (x0, y0)],
                 closed=True)
 
 fig, ax = plt.subplots(figsize=(3, 3))