matplotlib · timhoffm · Mar 4, 2026 · Feb 12, 2026 · Feb 12, 2026 · Feb 13, 2026
diff --git a/lib/matplotlib/mpl-data/matplotlibrc b/lib/matplotlib/mpl-data/matplotlibrc
@@ -451,7 +451,7 @@
                             # See also https://matplotlib.org/stable/api/toolkits/mplot3d/view_angles.html#rotation-with-mouse
 #axes3d.trackballsize: 0.667  # trackball diameter, in units of the Axes bbox
 #axes3d.trackballborder: 0.2  # trackball border width, in units of the Axes bbox (only for 'sphere' and 'arcball' style)
-
+#axes3d.snap_rotation: 0.0  # Snap angle (degrees) for 3D rotation when holding Control.
 ## ***************************************************************************
 ## * AXIS                                                                    *
 ## ***************************************************************************

diff --git a/lib/matplotlib/rcsetup.py b/lib/matplotlib/rcsetup.py
@@ -1181,6 +1181,7 @@ def _convert_validator_spec(key, conv):
     "axes3d.mouserotationstyle": ["azel", "trackball", "sphere", "arcball"],
     "axes3d.trackballsize": validate_float,
     "axes3d.trackballborder": validate_float,
+    "axes3d.snap_rotation": validate_float,
 
     # scatter props
     "scatter.marker":     _validate_marker,
@@ -2143,6 +2144,12 @@ class _Param:
         description="trackball border width, in units of the Axes bbox (only for "
                     "'sphere' and 'arcball' style)"
     ),
+    _Param(
+        "axes3d.snap_rotation",
+        default=0.0,
+        validator=validate_float,
+        description="Snap angle (in degrees) for 3D rotation when holding Control."
+   ),
     _Param(
         "xaxis.labellocation",
         default="center",

diff --git a/lib/matplotlib/typing.py b/lib/matplotlib/typing.py
@@ -222,6 +222,7 @@
     "axes3d.grid",
     "axes3d.mouserotationstyle",
     "axes3d.trackballborder",
+    "axes3d.snap_rotation",
     "axes3d.trackballsize",
     "axes3d.xaxis.panecolor",
     "axes3d.yaxis.panecolor",

diff --git a/lib/mpl_toolkits/mplot3d/axes3d.py b/lib/mpl_toolkits/mplot3d/axes3d.py
@@ -1597,6 +1597,10 @@ def _on_move(self, event):
 
                 q = dq * q
                 elev, azim, roll = np.rad2deg(q.as_cardan_angles())
+            step = mpl.rcParams["axes3d.snap_rotation"]
+            if step > 0 and getattr(event, "key", None) == "control":
+                elev = step * round(elev / step)
+                azim = step * round(azim / step)
 
             # update view
             vertical_axis = self._axis_names[self._vertical_axis]

diff --git a/lib/mpl_toolkits/mplot3d/tests/test_axes3d.py b/lib/mpl_toolkits/mplot3d/tests/test_axes3d.py
@@ -2785,3 +2785,72 @@ def test_axis_get_tightbbox_includes_offset_text():
             f"bbox.x1 ({bbox.x1}) should be >= offset_bbox.x1 ({offset_bbox.x1})"
         assert bbox.y1 >= offset_bbox.y1 - 1e-6, \
             f"bbox.y1 ({bbox.y1}) should be >= offset_bbox.y1 ({offset_bbox.y1})"
+
+
+def test_ctrl_rotation_snaps_to_5deg(monkeypatch):
+    fig = plt.figure()
+    ax = fig.add_subplot(projection="3d")
+    fig.canvas.draw()
+
+    # Initial angles
+    initial_elev = 12.3
+    initial_azim = 33.7
+
+    ax.elev = initial_elev
+    ax.azim = initial_azim
+
+    # Enable snapping
+    monkeypatch.setitem(
+        plt.rcParams,
+        "axes3d.snap_rotation",
+        5,
+    )
+    monkeypatch.setitem(
+        plt.rcParams,
+        "axes3d.mouserotationstyle",
+        "azel",
+    )
+
+    captured = {}
+
+    # Capture snapped values
+    def fake_view_init(elev=None, azim=None, **kwargs):
+        captured["elev"] = kwargs.get("elev", elev)
+        captured["azim"] = kwargs.get("azim", azim)
+
+    monkeypatch.setattr(ax, "view_init", fake_view_init)
+
+    press_event = MouseEvent(
+        "button_press_event",
+        fig.canvas,
+        x=100,
+        y=100,
+        button=1,
+    )
+    press_event.inaxes = ax
+    ax._button_press(press_event)
+
+    ax._sx, ax._sy = press_event.x, press_event.y
+
+    move_event = MouseEvent(
+        "motion_notify_event",
+        fig.canvas,
+        x=120,
+        y=120,
+        button=1,
+        key="control",
+    )
+    move_event.inaxes = ax
+
+
+    ax._on_move(move_event)
+
+    step = plt.rcParams["axes3d.snap_rotation"]
+
+    expected_elev = step * round(initial_elev / step)
+    expected_azim = step * round(initial_azim / step)
+
+    assert captured["elev"] == pytest.approx(expected_elev)
+    assert captured["azim"] == pytest.approx(expected_azim)
+
+    plt.close(fig)