Jun 10, 2025 · Nov 26, 2024
diff --git a/lib/matplotlib/backends/backend_agg.py b/lib/matplotlib/backends/backend_agg.py
        xo, yo = font.get_bitmap_offset()
        xo /= 64.0
        yo /= 64.0
        xd = d * sin(radians(angle))
        yd = d * cos(radians(angle))
        x = round(x + xo + xd)
        y = round(y + yo + yd)

        rad = radians(angle)
        xd = d * sin(rad)
        yd = d * cos(rad)
        # Rotating the offset vector ensures text rotates around the anchor point.
        # Without this, rotated text offsets incorrectly, causing a horizontal shift.
        # Applying the 2D rotation matrix.
        rotated_xo = xo * cos(rad) - yo * sin(rad)
        rotated_yo = xo * sin(rad) + yo * cos(rad)
        # Subtract rotated_yo to account for the inverted y-axis in computer graphics,
        # compared to the mathematical convention.
        x = round(x + rotated_xo + xd)
        y = round(y - rotated_yo + yd)

        self._renderer.draw_text_image(font, x, y + 1, angle, gc)

    def get_text_width_height_descent(self, s, prop, ismath):
diff --git a/lib/matplotlib/tests/baseline_images/test_text/rotation_anchor.png b/lib/matplotlib/tests/baseline_images/test_text/rotation_anchor.png
diff --git a/lib/matplotlib/tests/test_text.py b/lib/matplotlib/tests/test_text.py
    ax.set_yticks([])


 @image_comparison(baseline_images=['rotation_anchor.png'], style='mpl20',
                  remove_text=True)
 def test_rotation_mode_anchor():
    fig, ax = plt.subplots()

    ax.plot([0, 1], lw=0)
    ax.axvline(.5, linewidth=.5, color='.5')
    ax.axhline(.5, linewidth=.5, color='.5')

    N = 4
    for r in range(N):
        ax.text(.5, .5, 'pP', color=f'C{r}', size=100,
                rotation=r/N*360, rotation_mode='anchor',
                verticalalignment='center_baseline')


 @image_comparison(['axes_titles.png'])
 def test_axes_titles():
    # Related to issue #3327
Original file line number	Diff line number	Diff line change
Expand Up		@@ -197,10 +197,20 @@ def draw_text(self, gc, x, y, s, prop, angle, ismath=False, mtext=None):
		xo, yo = font.get_bitmap_offset()
		xo /= 64.0
		yo /= 64.0
		xd = d * sin(radians(angle))
		yd = d * cos(radians(angle))
		x = round(x + xo + xd)
		y = round(y + yo + yd)

		rad = radians(angle)
		xd = d * sin(rad)
		yd = d * cos(rad)
		# Rotating the offset vector ensures text rotates around the anchor point.
		# Without this, rotated text offsets incorrectly, causing a horizontal shift.
		# Applying the 2D rotation matrix.
		rotated_xo = xo * cos(rad) - yo * sin(rad)
		rotated_yo = xo * sin(rad) + yo * cos(rad)
		# Subtract rotated_yo to account for the inverted y-axis in computer graphics,
		# compared to the mathematical convention.
		x = round(x + rotated_xo + xd)
		y = round(y - rotated_yo + yd)

		self._renderer.draw_text_image(font, x, y + 1, angle, gc)

		def get_text_width_height_descent(self, s, prop, ismath):
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -301,6 +301,22 @@ def test_alignment():
		ax.set_yticks([])


		@image_comparison(baseline_images=['rotation_anchor.png'], style='mpl20',
		remove_text=True)
		def test_rotation_mode_anchor():
		fig, ax = plt.subplots()

		ax.plot([0, 1], lw=0)
		ax.axvline(.5, linewidth=.5, color='.5')
		ax.axhline(.5, linewidth=.5, color='.5')

		N = 4
		for r in range(N):
		ax.text(.5, .5, 'pP', color=f'C{r}', size=100,
		rotation=r/N*360, rotation_mode='anchor',
		verticalalignment='center_baseline')


		@image_comparison(['axes_titles.png'])
		def test_axes_titles():
		# Related to issue #3327
Expand Down