From 762c935fb0c4714990b15b8329b607f1ebc0257e Mon Sep 17 00:00:00 2001
From: SoftFever <softfeverever@gmail.com>
Date: Fri, 8 May 2026 00:31:35 +0800
Subject: [PATCH] Fixed regression bug that MANUAL_TOOL_CHANGE not working for
 BBL printers (#13516)
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* fix: manual filament change not emitting MANUAL_TOOL_CHANGE for BBL printers
BBL-specific M1020 S handling in toolchange() bypassed toolchange_prefix(),so manual_filament_change had no effect — M1020 was always emitted regardless of the setting. Move the BBL logic into toolchange_prefix() so all callers respect the option consistently.
Fixes #11795

* add comment
---
 src/libslic3r/GCodeWriter.cpp | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/src/libslic3r/GCodeWriter.cpp b/src/libslic3r/GCodeWriter.cpp
index 270de27a2c..a5e1c6abf1 100644
--- a/src/libslic3r/GCodeWriter.cpp
+++ b/src/libslic3r/GCodeWriter.cpp
@@ -506,9 +506,20 @@ std::string GCodeWriter::update_progress(unsigned int num, unsigned int tot, boo
 
 std::string GCodeWriter::toolchange_prefix() const
 {
-    return config.manual_filament_change ? ";" + GCodeProcessor::reserved_tag(GCodeProcessor::ETags::Manual_Tool_Change) + "T":
-           FLAVOR_IS(gcfMakerWare) ? "M135 T" :
-           FLAVOR_IS(gcfSailfish)  ? "M108 T" : "T";
+    std::string gcode = "T";
+    if (config.manual_filament_change)
+        gcode = ";" + GCodeProcessor::reserved_tag(GCodeProcessor::ETags::Manual_Tool_Change) + "T";
+    else {
+        if (m_is_bbl_printers)
+            gcode = "M1020 S";
+        else {
+            if (FLAVOR_IS(gcfMakerWare))
+                gcode = "M135 T";
+            else if (FLAVOR_IS(gcfSailfish))
+                gcode = "M108 T";
+        }
+    }
+    return gcode;
 }
 
 std::string GCodeWriter::toolchange(unsigned int filament_id)
@@ -523,12 +534,8 @@ std::string GCodeWriter::toolchange(unsigned int filament_id)
     // if we are running a single-extruder setup, just set the extruder and return nothing
     std::ostringstream gcode;
     if (this->multiple_extruders || (this->config.filament_diameter.values.size() > 1 && !is_bbl_printers())) {
-        // BBS
-        if (this->m_is_bbl_printers)
-            gcode << "M1020 S" << filament_id;
-        else
-            gcode << this->toolchange_prefix() << filament_id;
-        //BBS
+        // Orca: call toolchange_prefix() to get the correct command prefix based on the configuration and flavor.
+        gcode << this->toolchange_prefix() << filament_id;
         if (GCodeWriter::full_gcode_comment)
             gcode << " ; change extruder";
         gcode << "\n";