Hide active nozzle in Marlin.

Marlin shows three extruders on a dual:

   Extruder    - The active nozzle (varies)
   Extruder 1  - The primary extruder
   Extruder 2  - The secondary extruder

Hide first on the menu screens since seeing three nozzles may be confusing to users.

Marlin/Conditionals_LulzBot.h

@@ -62,7 +62,7 @@
     #error      Angelfish_Aero           // Titan AERO (Angelfish)
 #endif
 
-#define LULZBOT_FW_VERSION ".17"
+#define LULZBOT_FW_VERSION ".18"
 
 // Select options based on printer model
 
@@ -357,9 +357,16 @@
         // In the experimental Gladiola_GLCD, the encoder direction is reversed.
         #define LULZBOT_REVERSE_ENCODER_DIRECTION
     #endif
-    // Confusingly, Marlin shows three separate e-step settings: the active nozzle, nozzle1, nozzle2.
+    / * Marlin shows three extruders on a dual:
-    // We hide the first since it is redundant.
+      *   Extruder    - The active nozzle (varies)
-    #define LULZBOT_HIDE_E_STEPS_FOR_ACTIVE_NOZZLE
+      *   Extruder 1  - The primary extruder
+      *   Extruder 2  - The secondary extruder
+      *
+      * The following causes the active nozzle to be
+      * hidden as seeing three nozzles may be
+      * confusing to users.
+      */
+    #define LULZBOT_HIDE_ACTIVE_NOZZLE_IN_LCD
 #endif
 
 /*********************************************** COMMON TOOLHEADS PARAMETERS *****************************/

Marlin/ultralcd.cpp

@@ -1224,7 +1224,9 @@ void kill_screen(const char* lcd_msg) {
     #if EXTRUDERS == 1
       MENU_ITEM_EDIT(int3, MSG_FLOW, &flow_percentage[0], 10, 999);
     #else // EXTRUDERS > 1
+      #if not defined(LULZBOT_HIDE_ACTIVE_NOZZLE_IN_LCD)
       MENU_ITEM_EDIT(int3, MSG_FLOW, &flow_percentage[active_extruder], 10, 999);
+      #endif
       MENU_ITEM_EDIT(int3, MSG_FLOW MSG_N1, &flow_percentage[0], 10, 999);
       MENU_ITEM_EDIT(int3, MSG_FLOW MSG_N2, &flow_percentage[1], 10, 999);
       #if EXTRUDERS > 2
@@ -3172,7 +3174,9 @@ void kill_screen(const char* lcd_msg) {
     MENU_ITEM_EDIT(float3, MSG_VMAX MSG_Z, &planner.max_feedrate_mm_s[Z_AXIS], 1, 999);
 
     #if ENABLED(DISTINCT_E_FACTORS)
+      #if not defined(LULZBOT_HIDE_ACTIVE_NOZZLE_IN_LCD)
       MENU_ITEM_EDIT(float3, MSG_VMAX MSG_E, &planner.max_feedrate_mm_s[E_AXIS + active_extruder], 1, 999);
+      #endif
       MENU_ITEM_EDIT(float3, MSG_VMAX MSG_E1, &planner.max_feedrate_mm_s[E_AXIS], 1, 999);
       MENU_ITEM_EDIT(float3, MSG_VMAX MSG_E2, &planner.max_feedrate_mm_s[E_AXIS + 1], 1, 999);
       #if E_STEPPERS > 2
@@ -3217,7 +3221,9 @@ void kill_screen(const char* lcd_msg) {
     MENU_ITEM_EDIT_CALLBACK(long5, MSG_AMAX MSG_Z, &planner.max_acceleration_mm_per_s2[Z_AXIS], 10, 99000, _reset_acceleration_rates);
 
     #if ENABLED(DISTINCT_E_FACTORS)
+      #if not defined(LULZBOT_HIDE_ACTIVE_NOZZLE_IN_LCD)
       MENU_ITEM_EDIT_CALLBACK(long5, MSG_AMAX MSG_E, &planner.max_acceleration_mm_per_s2[E_AXIS + active_extruder], 100, 99000, _reset_acceleration_rates);
+      #endif
       MENU_ITEM_EDIT_CALLBACK(long5, MSG_AMAX MSG_E1, &planner.max_acceleration_mm_per_s2[E_AXIS], 100, 99000, _reset_e0_acceleration_rate);
       MENU_ITEM_EDIT_CALLBACK(long5, MSG_AMAX MSG_E2, &planner.max_acceleration_mm_per_s2[E_AXIS + 1], 100, 99000, _reset_e1_acceleration_rate);
       #if E_STEPPERS > 2
@@ -3263,7 +3269,7 @@ void kill_screen(const char* lcd_msg) {
     MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(float62, MSG_ZSTEPS, &planner.axis_steps_per_mm[Z_AXIS], 5, 9999, _planner_refresh_positioning);
 
     #if ENABLED(DISTINCT_E_FACTORS)
-      #if not defined(LULZBOT_HIDE_E_STEPS_FOR_ACTIVE_NOZZLE)
+      #if not defined(LULZBOT_HIDE_ACTIVE_NOZZLE_IN_LCD)
       MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(float62, MSG_ESTEPS, &planner.axis_steps_per_mm[E_AXIS + active_extruder], 5, 9999, _planner_refresh_positioning);
       #endif
       MENU_MULTIPLIER_ITEM_EDIT_CALLBACK(float62, MSG_E1STEPS, &planner.axis_steps_per_mm[E_AXIS], 5, 9999, _planner_refresh_e0_positioning);