Implemented new placeholders for output file name:

1) "initial_filament_type", "printing_filament_types" - really useful
   for multi-material prints

the two other are not so useful, they may become useful once
the output file name template will support not yet defined
vector variables:
2) "initial_tool", "initial_extruder" - zero based index of first extruder
3) "num_printing_extruders" - number of printing extruders.

Fixes Filename incorrect when exporting G-Code with MMU. Always refers filament type in extruder 1 #5300
Fixes Export Filename nicht richtig #7673
Fixes wrong filename - always Filament in from the first extruder #7684

src/libslic3r/Config.hpp

@@ -758,6 +758,8 @@ class ConfigOptionIntsTempl : public ConfigOptionVector<int>
     ConfigOptionIntsTempl() : ConfigOptionVector<int>() {}
     explicit ConfigOptionIntsTempl(size_t n, int value) : ConfigOptionVector<int>(n, value) {}
     explicit ConfigOptionIntsTempl(std::initializer_list<int> il) : ConfigOptionVector<int>(std::move(il)) {}
+    explicit ConfigOptionIntsTempl(const std::vector<int> &v) : ConfigOptionVector<int>(v) {}
+    explicit ConfigOptionIntsTempl(std::vector<int> &&v) : ConfigOptionVector<int>(std::move(v)) {}
 
     static ConfigOptionType static_type() { return coInts; }
     ConfigOptionType        type()  const override { return static_type(); }

src/libslic3r/GCode.cpp

@@ -677,7 +677,7 @@ namespace DoExport {
         print_statistics.total_weight          = total_weight;
         print_statistics.total_cost            = total_cost;
 
-        print_statistics.filament_stats = result.print_statistics.volumes_per_extruder;
+        print_statistics.filament_stats        = result.print_statistics.volumes_per_extruder;
     }
 
     // if any reserved keyword is found, returns a std::vector containing the first MAX_COUNT keywords found
@@ -984,19 +984,26 @@ namespace DoExport {
     static std::string update_print_stats_and_format_filament_stats(
         const bool                   has_wipe_tower,
 	    const WipeTowerData         &wipe_tower_data,
+        const FullPrintConfig       &config,
 	    const std::vector<Extruder> &extruders,
+        unsigned int                 initial_extruder_id,
 		PrintStatistics 		    &print_statistics)
     {
 		std::string filament_stats_string_out;
 
 	    print_statistics.clear();
         print_statistics.total_toolchanges = std::max(0, wipe_tower_data.number_of_toolchanges);
+        print_statistics.initial_extruder_id = initial_extruder_id;
+        std::vector<std::string> filament_types;
 	    if (! extruders.empty()) {
 	        std::pair<std::string, unsigned int> out_filament_used_mm ("; filament used [mm] = ", 0);
 	        std::pair<std::string, unsigned int> out_filament_used_cm3("; filament used [cm3] = ", 0);
 	        std::pair<std::string, unsigned int> out_filament_used_g  ("; filament used [g] = ", 0);
 	        std::pair<std::string, unsigned int> out_filament_cost    ("; filament cost = ", 0);
 	        for (const Extruder &extruder : extruders) {
+                print_statistics.printing_extruders.emplace_back(extruder.id());
+                filament_types.emplace_back(config.filament_type.get_at(extruder.id()));
+
 	            double used_filament   = extruder.used_filament() + (has_wipe_tower ? wipe_tower_data.used_filament[extruder.id()] : 0.f);
 	            double extruded_volume = extruder.extruded_volume() + (has_wipe_tower ? wipe_tower_data.used_filament[extruder.id()] * 2.4052f : 0.f); // assumes 1.75mm filament diameter
 	            double filament_weight = extruded_volume * extruder.filament_density() * 0.001;
@@ -1036,6 +1043,13 @@ namespace DoExport {
                 filament_stats_string_out += "\n" + out_filament_used_g.first;
             if (out_filament_cost.second)
                 filament_stats_string_out += "\n" + out_filament_cost.first;
+            print_statistics.initial_filament_type = config.filament_type.values[initial_extruder_id];
+            std::sort(filament_types.begin(), filament_types.end());
+            print_statistics.printing_filament_types = filament_types.front();
+            for (size_t i = 1; i < filament_types.size(); ++ i) {
+                print_statistics.printing_filament_types += ",";
+                print_statistics.printing_filament_types += filament_types[i];
+            }
         }
         return filament_stats_string_out;
     }
@@ -1486,7 +1500,9 @@ void GCode::_do_export(Print& print, GCodeOutputStream &file, ThumbnailsGenerato
     file.write(DoExport::update_print_stats_and_format_filament_stats(
     	// Const inputs
         has_wipe_tower, print.wipe_tower_data(),
+        this->config(),
         m_writer.extruders(),
+        initial_extruder_id,
         // Modifies
         print.m_print_statistics));
     file.write("\n");

src/libslic3r/Print.cpp

@@ -1248,6 +1248,13 @@ DynamicConfig PrintStatistics::config() const
     config.set_key_value("total_weight",              new ConfigOptionFloat(this->total_weight));
     config.set_key_value("total_wipe_tower_cost",     new ConfigOptionFloat(this->total_wipe_tower_cost));
     config.set_key_value("total_wipe_tower_filament", new ConfigOptionFloat(this->total_wipe_tower_filament));
+    config.set_key_value("initial_tool",              new ConfigOptionInt(int(this->initial_extruder_id)));
+    config.set_key_value("initial_extruder",          new ConfigOptionInt(int(this->initial_extruder_id)));
+    config.set_key_value("initial_filament_type",     new ConfigOptionString(this->initial_filament_type));
+    config.set_key_value("printing_filament_types",   new ConfigOptionString(this->printing_filament_types));
+    config.set_key_value("num_printing_extruders",    new ConfigOptionInt(int(this->printing_extruders.size())));
+//    config.set_key_value("printing_extruders",        new ConfigOptionInts(std::vector<int>(this->printing_extruders.begin(), this->printing_extruders.end())));
+
     return config;
 }
 
@@ -1257,7 +1264,8 @@ DynamicConfig PrintStatistics::placeholders()
     for (const std::string &key : { 
         "print_time", "normal_print_time", "silent_print_time", 
         "used_filament", "extruded_volume", "total_cost", "total_weight", 
-        "total_toolchanges", "total_wipe_tower_cost", "total_wipe_tower_filament"})
+        "total_toolchanges", "total_wipe_tower_cost", "total_wipe_tower_filament",
+        "initial_tool", "initial_extruder", "initial_filament_type", "printing_filament_types", "num_printing_extruders" })
         config.set_key_value(key, new ConfigOptionString(std::string("{") + key + "}"));
     return config;
 }

src/libslic3r/Print.hpp

@@ -455,6 +455,10 @@ struct PrintStatistics
     double                          total_weight;
     double                          total_wipe_tower_cost;
     double                          total_wipe_tower_filament;
+    std::vector<unsigned int>       printing_extruders;
+    unsigned int                    initial_extruder_id;
+    std::string                     initial_filament_type;
+    std::string                     printing_filament_types;
     std::map<size_t, double>        filament_stats;
 
     // Config with the filled in print statistics.
@@ -472,7 +476,11 @@ struct PrintStatistics
         total_weight           = 0.;
         total_wipe_tower_cost  = 0.;
         total_wipe_tower_filament = 0.;
+        initial_extruder_id    = 0;
+        initial_filament_type.clear();
+        printing_filament_types.clear();
         filament_stats.clear();
+        printing_extruders.clear();
     }
 };