[Bug fix] Fixes retraction on layer change being performed when retract travel threshold is set to 0

src/libslic3r/GCode/SpiralVase.cpp

@@ -126,7 +126,9 @@ std::string SpiralVase::process_layer(const std::string &gcode, bool last_layer)
     m_reader.parse_buffer(gcode, [&new_gcode, &z, total_layer_length, layer_height, transition_in, &len, &current_layer, &previous_layer, &transition_gcode, transition_out, smooth_spiral, &max_xy_dist_for_smoothing, &last_point]
         (GCodeReader &reader, GCodeReader::GCodeLine line) {
         if (line.cmd_is("G1")) {
-            if (line.has_z()) {
+            // Orca: Filter out retractions at layer change
+            if (line.retracting(reader) || (line.extruding(reader) && line.dist_XY(reader) < EPSILON)) return;
+            if (line.has_z() && !line.retracting(reader)) {
                 // If this is the initial Z move of the layer, replace it with a
                 // (redundant) move to the last Z of previous layer.
                 line.set(reader, Z, z);