Don't add prime tower area if single extrusion

Simple papercut fix.

1 files changed, 14 insertions, 13 deletions

diff --git a/cura/BuildVolume.py b/cura/BuildVolume.py
index fbf4ba5080..9c22d5ae3a 100755
--- a/cura/BuildVolume.py
+++ b/cura/BuildVolume.py
@@ -600,20 +600,21 @@ class BuildVolume(SceneNode):
                 result_areas[extruder_id].append(polygon) #Don't perform the offset on these.
 
         # Add prime tower location as disallowed area.
-        prime_tower_collision = False
-        prime_tower_areas = self._computeDisallowedAreasPrinted(used_extruders)
-        for extruder_id in prime_tower_areas:
-            for prime_tower_area in prime_tower_areas[extruder_id]:
-                for area in result_areas[extruder_id]:
-                    if prime_tower_area.intersectsPolygon(area) is not None:
-                        prime_tower_collision = True
+        if len(used_extruders) > 1: #No prime tower in single-extrusion.
+            prime_tower_collision = False
+            prime_tower_areas = self._computeDisallowedAreasPrinted(used_extruders)
+            for extruder_id in prime_tower_areas:
+                for prime_tower_area in prime_tower_areas[extruder_id]:
+                    for area in result_areas[extruder_id]:
+                        if prime_tower_area.intersectsPolygon(area) is not None:
+                            prime_tower_collision = True
+                            break
+                    if prime_tower_collision: #Already found a collision.
                         break
-                if prime_tower_collision: #Already found a collision.
-                    break
-            if not prime_tower_collision:
-                result_areas[extruder_id].extend(prime_tower_areas[extruder_id])
-            else:
-                self._error_areas.extend(prime_tower_areas[extruder_id])
+                if not prime_tower_collision:
+                    result_areas[extruder_id].extend(prime_tower_areas[extruder_id])
+                else:
+                    self._error_areas.extend(prime_tower_areas[extruder_id])
 
         self._has_errors = len(self._error_areas) > 0