csaxs_bec/bec_ipython_client/plugins/LamNI/x_ray_eye_align.py

@@ -129,6 +129,21 @@ class XrayEyeAlign:
     def get_tomo_angle(self) -> float:
         return self.device_manager.devices.lsamrot.readback.read()["lsamrot"]["value"]
 
+    def _tomo_rotate_if_needed(self, val: float, tol: float = 0.05):
+        """Rotate lsamrot to `val` unless it's already there.
+
+        Used right after loptics_out(), which -- when rtx is enabled -- already
+        drives lsamrot to 0 via feedback_enable_with_reset()
+        (RtLamniController.feedback_enable_with_reset() in rt_lamni_ophyd.py).
+        Re-issuing the same move there would be a redundant round trip; this
+        still corrects the small residual drift that can creep in while
+        feedback briefly runs between that internal move and the explicit
+        _disable_rt_feedback() call, and still moves lsamrot when rtx is
+        disabled (loptics_out() then never touches it at all).
+        """
+        if not np.isclose(self.get_tomo_angle(), val, atol=tol):
+            self.tomo_rotate(val)
+
     def _disable_rt_feedback(self):
         self.device_manager.devices.rtx.controller.feedback_disable()
 
@@ -836,7 +851,7 @@ class XrayEyeAlign:
         self.send_message("Please wait - moving sample in...")
         self.lamni.loptics_out()
         self._disable_rt_feedback()
-        self.tomo_rotate(0)
+        self._tomo_rotate_if_needed(0)
         self.update_frame(keep_shutter_open)
         self.gui.set_crosshair_position(fzp_x / self.pixel_calibration, fzp_y / self.pixel_calibration)
         self.gui.show_crosshair()
@@ -1126,7 +1141,7 @@ class XrayEyeAlign:
         self.send_message("Please wait - moving sample in...")
         self.lamni.loptics_out()
         self._disable_rt_feedback()
-        self.tomo_rotate(0)
+        self._tomo_rotate_if_needed(0)
         self.update_frame(keep_shutter_open)
         self.gui.set_crosshair_position(fzp_x / self.pixel_calibration, fzp_y / self.pixel_calibration)
         self.gui.show_crosshair()