From 386f49fb664b3b9ad99ad838bdaceae593b4505e Mon Sep 17 00:00:00 2001
From: Luca Toniolo <10792599+grandixximo@users.noreply.github.com>
Date: Tue, 29 Sep 2026 22:24:57 +1000
Subject: [PATCH] qtvcp: write the var file before reloading the preview on
 offset changes

The preview reads offsets from the var file, which the interpreter only writes when it synchs. Offset actions reloaded before that happened: the CALL_MDI ones did not wait for the MDI, and the others had no mode change to trigger the write when already in MDI mode.

Run them through one helper that waits, requests a plan synch, restores the previous mode and reloads.
---
 lib/python/qtvcp/qt_action.py | 38 +++++++++++++++++------------------
 1 file changed, 19 insertions(+), 19 deletions(-)

diff --git a/lib/python/qtvcp/qt_action.py b/lib/python/qtvcp/qt_action.py
index 524282238d2..c853b734e45 100644
--- a/lib/python/qtvcp/qt_action.py
+++ b/lib/python/qtvcp/qt_action.py
@@ -415,12 +415,7 @@ def SET_AXIS_ORIGIN(self, axis, value):
         self.lastOriginSet[jnum] = r[jnum]
 
         # set new position
-        m = "G10 L20 P0 %s%f" % (axis, value)
-        fail, premode = self.ensure_mode(linuxcnc.MODE_MDI)
-        self.cmd.mdi(m)
-        self.cmd.wait_complete()
-        self.ensure_mode(premode)
-        self.RELOAD_DISPLAY()
+        self.set_offset_mdi("G10 L20 P0 %s%f" % (axis, value))
 
     def GET_LAST_RECORDED_ORIGIN(self, axis):
         j = "XYZABCUVW"
@@ -603,22 +598,16 @@ def SET_USER_SYSTEM(self, system):
             self.ensure_mode(premode)
 
     def ZERO_G92_OFFSET(self):
-        self.CALL_MDI("G92.1")
-        self.RELOAD_DISPLAY()
+        self.set_offset_mdi("G92.1")
 
     def ZERO_ROTATIONAL_OFFSET(self):
-        self.CALL_MDI("G10 L2 P0 R 0")
-        self.RELOAD_DISPLAY()
+        self.set_offset_mdi("G10 L2 P0 R 0")
 
     def ZERO_G5X_OFFSET(self, num):
-        fail, premode = self.ensure_mode(linuxcnc.MODE_MDI)
         clear_command = "G10 L2 P%d R0" % num
         for a in INFO.AVAILABLE_AXES:
             clear_command += " %c0" % a
-        self.cmd.mdi('%s' % clear_command)
-        self.cmd.wait_complete()
-        self.ensure_mode(premode)
-        self.RELOAD_DISPLAY()
+        self.set_offset_mdi(clear_command)
 
     def RECORD_CURRENT_MODE(self):
         mode = STATUS.get_current_mode()
@@ -838,15 +827,13 @@ def SET_LATHE_MIRROR_X(self):
         if not INFO.MACHINE_IS_LATHE:
             LOG.warning('Can not set mirror mode; Machine is not a lathe')
             return
-        self.CALL_MDI("G10 L2 P0 R180")
-        self.RELOAD_DISPLAY()
+        self.set_offset_mdi("G10 L2 P0 R180")
 
     def UNSET_LATHE_MIRROR_X(self):
         if not INFO.MACHINE_IS_LATHE:
             LOG.warning('Can not unset mirror mode; Machine is not a lathe')
             return
-        self.CALL_MDI("G10 L2 P0 R0")
-        self.RELOAD_DISPLAY()
+        self.set_offset_mdi("G10 L2 P0 R0")
 
     # Some systems need repeat disabled for keyboard jogging because repeat rate is uneven
     def DISABLE_AUTOREPEAT_KEYS(self, keys={'34','35','80','81','83','85','88','89','111','112','113','114','116','117'}):
@@ -1032,6 +1019,19 @@ def jnum_check(self, num):
             return None
         return num
 
+    # run an MDI command that changes offsets, then reload the preview
+    # the preview reads offsets from the var file, and the interpreter only
+    # writes it when it synchs, so synch explicitly: no mode change does it
+    # when the screen is already in MDI mode
+    def set_offset_mdi(self, code):
+        fail, premode = self.ensure_mode(linuxcnc.MODE_MDI)
+        self.cmd.mdi(code)
+        self.cmd.wait_complete()
+        self.cmd.task_plan_synch()
+        self.cmd.wait_complete()
+        self.ensure_mode(premode)
+        self.RELOAD_DISPLAY()
+
     # check and if required set the machine mode
     # return: state changed?, the original mode
     def ensure_mode(self, *modes):