From fb4230f80d3308af568ce35566fa5278e6c38c02 Mon Sep 17 00:00:00 2001
From: bubnikv <bubnikv@gmail.com>
Date: Wed, 7 Mar 2018 15:46:46 +0100
Subject: [PATCH] Fix of a regression bug, caused by pre-calculating the
 extrudemultiply for precission and performance:
 calculate_extruder_multipliers() has to be called after extrudemultiply is
 changed from the printer panel.

---
 Firmware/ultralcd.cpp | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/Firmware/ultralcd.cpp b/Firmware/ultralcd.cpp
index 9cd4a932..2c9f7f1f 100644
--- a/Firmware/ultralcd.cpp
+++ b/Firmware/ultralcd.cpp
@@ -90,6 +90,18 @@ union MenuData
         int    rear2;
     } adjustBed;
 
+    struct TuneMenu
+    {
+        // editMenuParentState is used when an edit menu is entered, so it knows
+        // the return menu and encoder state.
+        struct EditMenuParentState editMenuParentState;
+        // To recognize, whether the menu has been just initialized.
+        int8_t  status;
+        // Backup of extrudemultiply, to recognize, that the value has been changed and
+        // it needs to be applied.
+        int16_t extrudemultiply;
+    } tuneMenu;
+
     // editMenuParentState is used when an edit menu is entered, so it knows
     // the return menu and encoder state.
     struct EditMenuParentState editMenuParentState;
@@ -5443,6 +5455,16 @@ static void lcd_colorprint_change() {
 
 static void lcd_tune_menu()
 {
+  if (menuData.tuneMenu.status == 0) {
+    // Menu was entered. Mark the menu as entered and save the current extrudemultiply value.
+    menuData.tuneMenu.status = 1;
+    menuData.tuneMenu.extrudemultiply = extrudemultiply;
+  } else if (menuData.tuneMenu.extrudemultiply != extrudemultiply) {
+    // extrudemultiply has been changed from the child menu. Apply the new value.
+    menuData.tuneMenu.extrudemultiply = extrudemultiply;
+    calculate_extruder_multipliers();
+  }
+
   EEPROM_read(EEPROM_SILENT, (uint8_t*)&SilentModeMenu, sizeof(SilentModeMenu));