From a6f0bd4d28c4a26288f8fe9c33f017c9e8c37286 Mon Sep 17 00:00:00 2001
From: SoftFever <103989404+SoftFever@users.noreply.github.com>
Date: Mon, 16 Jan 2023 20:59:10 +0800
Subject: [PATCH] Allow 100% retract before wipe

Signed-off-by: SoftFever <103989404+SoftFever@users.noreply.github.com>
---
 src/libslic3r/GCode.cpp       | 4 +++-
 src/libslic3r/GCodeWriter.cpp | 3 +++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/libslic3r/GCode.cpp b/src/libslic3r/GCode.cpp
index 7842f7f4dc..daa95e0bb3 100644
--- a/src/libslic3r/GCode.cpp
+++ b/src/libslic3r/GCode.cpp
@@ -180,7 +180,9 @@ bool GCode::gcode_label_objects = true;
         // Shorten the retraction length by the amount already retracted before wipe.
         length *= (1. - gcodegen.writer().extruder()->retract_before_wipe());
 
-        if (length > 0) {
+        //SoftFever: allow 100% retract before wipe
+//        if (length > 0)
+        {
             /*  Calculate how long we need to travel in order to consume the required
                 amount of retraction. In other words, how far do we move in XY at wipe_speed
                 for the time needed to consume retraction_length at retraction_speed?  */
diff --git a/src/libslic3r/GCodeWriter.cpp b/src/libslic3r/GCodeWriter.cpp
index 0b58d9fbe7..2ebfc181fc 100644
--- a/src/libslic3r/GCodeWriter.cpp
+++ b/src/libslic3r/GCodeWriter.cpp
@@ -504,6 +504,9 @@ std::string GCodeWriter::extrude_to_xy(const Vec2d &point, double dE, const std:
 {
     m_pos(0) = point(0);
     m_pos(1) = point(1);
+    if(std::abs(dE) <= std::numeric_limits<double>::epsilon())
+        force_no_extrusion = true;
+    
     if (!force_no_extrusion)
         m_extruder->extrude(dE);