From c6f694a247783443e2b6ee57e635202bf2e301b3 Mon Sep 17 00:00:00 2001
From: The-Force <dforce@gmail.com>
Date: Thu, 31 Oct 2019 20:09:37 +0100
Subject: [PATCH] Power Loss Recovery for volumetric extrusion (#15734)

---
 Marlin/src/feature/power_loss_recovery.cpp | 30 ++++++++++++++++++++++
 Marlin/src/feature/power_loss_recovery.h   |  9 +++++++
 2 files changed, 39 insertions(+)

diff --git a/Marlin/src/feature/power_loss_recovery.cpp b/Marlin/src/feature/power_loss_recovery.cpp
index c438dffa3..1cea125df 100644
--- a/Marlin/src/feature/power_loss_recovery.cpp
+++ b/Marlin/src/feature/power_loss_recovery.cpp
@@ -183,6 +183,15 @@ void PrintJobRecovery::save(const bool force/*=false*/, const bool save_queue/*=
       info.active_extruder = active_extruder;
     #endif
 
+    #if DISABLED(NO_VOLUMETRICS)
+      info.volumetric_enabled = parser.volumetric_enabled;
+      #if EXTRUDERS > 1
+        for (int8_t e = 0; e < EXTRUDERS; e++) info.filament_size[e] = planner.filament_size[e];
+      #else
+        if (parser.volumetric_enabled) info.filament_size = planner.filament_size[active_extruder]; 
+      #endif    
+    #endif
+
     #if EXTRUDERS
       HOTEND_LOOP() info.target_temperature[e] = thermalManager.temp_hotend[e].target;
     #endif
@@ -291,6 +300,27 @@ void PrintJobRecovery::resume() {
     gcode.process_subcommands_now(cmd);
   #endif
 
+  // Recover volumetric extrusion state
+  #if DISABLED(NO_VOLUMETRICS)    
+    #if EXTRUDERS > 1
+      for (int8_t e = 0; e < EXTRUDERS; e++) {
+        dtostrf(info.filament_size[e], 1, 3, str_1);
+        sprintf_P(cmd, PSTR("M200 T%i D%s"), e, str_1);
+        gcode.process_subcommands_now(cmd);
+      }
+      if (!info.volumetric_enabled) {
+        sprintf_P(cmd, PSTR("M200 T%i D0"), info.active_extruder);
+        gcode.process_subcommands_now(cmd);
+      }
+    #else
+      if (info.volumetric_enabled) {
+        dtostrf(info.filament_size, 1, 3, str_1);
+        sprintf_P(cmd, PSTR("M200 D%s"), str_1);
+        gcode.process_subcommands_now(cmd);
+      }
+    #endif
+  #endif
+
   #if HAS_HEATED_BED
     const int16_t bt = info.target_temperature_bed;
     if (bt) {
diff --git a/Marlin/src/feature/power_loss_recovery.h b/Marlin/src/feature/power_loss_recovery.h
index 9f947701e..20248a2e4 100644
--- a/Marlin/src/feature/power_loss_recovery.h
+++ b/Marlin/src/feature/power_loss_recovery.h
@@ -59,6 +59,15 @@ typedef struct {
     uint8_t active_extruder;
   #endif
 
+  #if DISABLED(NO_VOLUMETRICS)
+    bool volumetric_enabled;
+    #if EXTRUDERS > 1
+      float filament_size[EXTRUDERS]; 
+    #else
+      float filament_size; 
+    #endif    
+  #endif
+
   #if HOTENDS
     int16_t target_temperature[HOTENDS];
   #endif