From e22d328fa9d1682c00617a4cad0498c67a7512f4 Mon Sep 17 00:00:00 2001
From: "zhimin.zeng" <zhimin.zeng@bambulab.com>
Date: Fri, 16 May 2025 11:48:54 +0800
Subject: [PATCH] ENH: Optimizing the shape invalid condition for wipe tower of
 multi-extruder

jira: none
Change-Id: Ic80a83088f409f0c4d4444c085befb6a1817c85b
---
 src/libslic3r/PrintApply.cpp | 53 +++++++++++++++++++++++++++++++++---
 1 file changed, 49 insertions(+), 4 deletions(-)

diff --git a/src/libslic3r/PrintApply.cpp b/src/libslic3r/PrintApply.cpp
index 69f760d17..59c2adfd8 100644
--- a/src/libslic3r/PrintApply.cpp
+++ b/src/libslic3r/PrintApply.cpp
@@ -288,6 +288,51 @@ static t_config_option_keys full_print_config_diffs(const DynamicPrintConfig &cu
     return full_config_diff;
 }
 
+static bool is_printable_filament_changed(const DynamicPrintConfig& new_full_config, const Polygon& old_poly, const Polygon& new_poly)
+{
+    if (old_poly != new_poly) {
+        auto map_mode_opt = new_full_config.option<ConfigOptionEnum<FilamentMapMode>>("filament_map_mode");
+        if (map_mode_opt && map_mode_opt->value == FilamentMapMode::fmmManual)
+            return false;
+
+        Pointfs              printable_area = new_full_config.option<ConfigOptionPoints>("printable_area")->values;
+        std::vector<Pointfs> extruder_areas = new_full_config.option<ConfigOptionPointsGroups>("extruder_printable_area")->values;
+        Points               pts;
+        for (auto pt : printable_area) { pts.emplace_back(Point(scale_(pt.x()), scale_(pt.y()))); }
+        Polygon printable_poly(pts);
+
+        std::vector<Polygon> extruder_polys;
+        for (auto extruder_area : extruder_areas) {
+            pts.clear();
+            for (auto pt : extruder_area) { pts.emplace_back(Point(scale_(pt.x()), scale_(pt.y()))); }
+            extruder_polys.emplace_back(Polygon(pts));
+        }
+
+        std::vector<Polygon> split_polys;
+        for (const Polygon poly : extruder_polys) {
+            Polygons res = diff(printable_poly, poly);
+            if (!res.empty()) { split_polys.emplace_back(res[0]); }
+        }
+
+        Polygons all_extruder_polys = intersection({printable_poly}, extruder_polys);
+        if (!all_extruder_polys.empty()) split_polys.emplace_back(all_extruder_polys[0]);
+
+        auto find_intersections = [](const Polygon &poly, const std::vector<Polygon> &contours) -> std::set<int> {
+            std::set<int> result;
+            for (size_t i = 0; i < contours.size(); ++i) {
+                if (!intersection(poly, contours[i]).empty()) { result.insert(static_cast<int>(i)); }
+            }
+            return result;
+        };
+
+        std::set<int> old_poly_ids = find_intersections(old_poly, split_polys);
+        std::set<int> new_poly_ids = find_intersections(new_poly, split_polys);
+
+        return old_poly_ids != new_poly_ids;
+    }
+    return false;
+}
+
 // Repository for solving partial overlaps of ModelObject::layer_config_ranges.
 // Here the const DynamicPrintConfig* point to the config in ModelObject::layer_config_ranges.
 class LayerRanges
@@ -1452,7 +1497,10 @@ Print::ApplyStatus Print::apply(const Model &model, DynamicPrintConfig new_full_
 	        	// Synchronize the content of instances.
 	        	auto new_instance = model_object_new.instances.begin();
 				for (auto old_instance = model_object.instances.begin(); old_instance != model_object.instances.end(); ++ old_instance, ++ new_instance) {
-					(*old_instance)->set_transformation((*new_instance)->get_transformation());
+                    if (is_printable_filament_changed(new_full_config, (*old_instance)->convex_hull_2d(), (*new_instance)->convex_hull_2d())) {
+                        update_apply_status(this->invalidate_steps({psWipeTower, psGCodeExport}));
+                    }
+                    (*old_instance)->set_transformation((*new_instance)->get_transformation());
                     (*old_instance)->print_volume_state = (*new_instance)->print_volume_state;
                     (*old_instance)->printable 		    = (*new_instance)->printable;
   				}
@@ -1515,9 +1563,6 @@ Print::ApplyStatus Print::apply(const Model &model, DynamicPrintConfig new_full_
 					PrintBase::ApplyStatus status = (*it_old)->print_object->set_instances(std::move(new_instances.instances));
                     if (status != PrintBase::APPLY_STATUS_UNCHANGED) {
                         size_t extruder_num = new_full_config.option<ConfigOptionFloatsNullable>("nozzle_diameter")->size();
-                        if (extruder_num > 1) {
-                            update_apply_status(this->invalidate_steps({ psWipeTower,psSkirtBrim, psGCodeExport }));
-                        }
                         update_apply_status(status == PrintBase::APPLY_STATUS_INVALIDATED);
                     }
 					print_objects_new.emplace_back((*it_old)->print_object);