Minor tweaks in machine limits handling:

- renamed some variables so the names are not misleading
- improved readability a bit
- disabled silent mode for RRF (it was apparently enabled by mistake)
- set default value of machine_limits_usage to TimeEstimateOnly

src/libslic3r/GCode.cpp

@@ -1685,9 +1685,10 @@ static bool custom_gcode_sets_temperature(const std::string &gcode, const int mc
 // Do not process this piece of G-code by the time estimator, it already knows the values through another sources.
 void GCode::print_machine_envelope(GCodeOutputStream &file, Print &print)
 {
-    if ((print.config().gcode_flavor.value == gcfMarlinLegacy || print.config().gcode_flavor.value == gcfMarlinFirmware || print.config().gcode_flavor.value == gcfRepRapFirmware)
+    const GCodeFlavor flavor = print.config().gcode_flavor.value;
+    if ( (flavor == gcfMarlinLegacy || flavor == gcfMarlinFirmware || flavor == gcfRepRapFirmware)
      && print.config().machine_limits_usage.value == MachineLimitsUsage::EmitToGCode) {
-        int factor = print.config().gcode_flavor.value == gcfRepRapFirmware ? 60 : 1; // RRF M203 and M566 are in mm/min
+        int factor = flavor == gcfRepRapFirmware ? 60 : 1; // RRF M203 and M566 are in mm/min
         file.write_format("M201 X%d Y%d Z%d E%d ; sets maximum accelerations, mm/sec^2\n",
             int(print.config().machine_max_acceleration_x.values.front() + 0.5),
             int(print.config().machine_max_acceleration_y.values.front() + 0.5),
@@ -1703,11 +1704,11 @@ void GCode::print_machine_envelope(GCodeOutputStream &file, Print &print)
         // backwards compatibility: https://github.com/prusa3d/PrusaSlicer/issues/1089
         // Legacy Marlin should export travel acceleration the same as printing acceleration.
         // MarlinFirmware has the two separated.
-        int travel_acc = print.config().gcode_flavor == gcfMarlinLegacy
+        int travel_acc = flavor == gcfMarlinLegacy
                        ? int(print.config().machine_max_acceleration_extruding.values.front() + 0.5)
                        : int(print.config().machine_max_acceleration_travel.values.front() + 0.5);
         // Retract acceleration not accepeted in M204 in RRF
-        if (print.config().gcode_flavor.value == gcfRepRapFirmware)
+        if (flavor == gcfRepRapFirmware)
             file.write_format("M204 P%d T%d ; sets acceleration (P, T), mm/sec^2\n",
                 int(print.config().machine_max_acceleration_extruding.values.front() + 0.5),
                 travel_acc);
@@ -1718,13 +1719,15 @@ void GCode::print_machine_envelope(GCodeOutputStream &file, Print &print)
                 travel_acc);
 
         assert(is_decimal_separator_point());
-        file.write_format(print.config().gcode_flavor.value == gcfRepRapFirmware ? "M566 X%.2lf Y%.2lf Z%.2lf E%.2lf ; sets the jerk limits, mm/min\n" : "M205 X%.2lf Y%.2lf Z%.2lf E%.2lf ; sets the jerk limits, mm/sec\n",
+        file.write_format(flavor == gcfRepRapFirmware
+            ? "M566 X%.2lf Y%.2lf Z%.2lf E%.2lf ; sets the jerk limits, mm/min\n"
+            : "M205 X%.2lf Y%.2lf Z%.2lf E%.2lf ; sets the jerk limits, mm/sec\n",
             print.config().machine_max_jerk_x.values.front() * factor,
             print.config().machine_max_jerk_y.values.front() * factor,
             print.config().machine_max_jerk_z.values.front() * factor,
             print.config().machine_max_jerk_e.values.front() * factor);
         // M205 Sn Tn not supported in RRF
-        if (print.config().gcode_flavor.value != gcfRepRapFirmware)
+        if (flavor != gcfRepRapFirmware)
             file.write_format("M205 S%d T%d ; sets the minimum extruding and travel feed rate, mm/sec\n",
                 int(print.config().machine_min_extruding_rate.values.front() + 0.5),
                 int(print.config().machine_min_travel_rate.values.front() + 0.5));

src/libslic3r/GCodeWriter.cpp

@@ -20,8 +20,10 @@ void GCodeWriter::apply_print_config(const PrintConfig &print_config)
     this->config.apply(print_config, true);
     m_extrusion_axis = get_extrusion_axis(this->config);
     m_single_extruder_multi_material = print_config.single_extruder_multi_material.value;
-    bool is_marlin = print_config.gcode_flavor.value == gcfMarlinLegacy || print_config.gcode_flavor.value == gcfMarlinFirmware || print_config.gcode_flavor.value == gcfRepRapFirmware;
+    bool use_mach_limits = print_config.gcode_flavor.value == gcfMarlinLegacy
-    m_max_acceleration = std::lrint((is_marlin && print_config.machine_limits_usage.value == MachineLimitsUsage::EmitToGCode) ?
+                        || print_config.gcode_flavor.value == gcfMarlinFirmware
+                        || print_config.gcode_flavor.value == gcfRepRapFirmware;
+    m_max_acceleration = std::lrint((use_mach_limits && print_config.machine_limits_usage.value == MachineLimitsUsage::EmitToGCode) ?
         print_config.machine_max_acceleration_extruding.values.front() : 0);
 }
 

src/libslic3r/PrintConfig.cpp

@@ -1614,7 +1614,7 @@ void PrintConfigDef::init_fff_params()
     def->enum_labels.push_back(L("Use for time estimate"));
     def->enum_labels.push_back(L("Ignore"));
     def->mode = comAdvanced;
-    def->set_default_value(new ConfigOptionEnum<MachineLimitsUsage>(MachineLimitsUsage::EmitToGCode));
+    def->set_default_value(new ConfigOptionEnum<MachineLimitsUsage>(MachineLimitsUsage::TimeEstimateOnly));
 
     {
         struct AxisDefault {

src/slic3r/GUI/Tab.cpp

@@ -2656,7 +2656,7 @@ void TabPrinter::build_unregular_pages(bool from_initial_build/* = false*/)
 {
     size_t		n_before_extruders = 2;			//	Count of pages before Extruder pages
     auto        flavor = m_config->option<ConfigOptionEnum<GCodeFlavor>>("gcode_flavor")->value;
-    bool		is_marlin_flavor = (flavor == gcfMarlinLegacy || flavor == gcfMarlinFirmware || flavor == gcfRepRapFirmware);
+    bool		show_mach_limits = (flavor == gcfMarlinLegacy || flavor == gcfMarlinFirmware || flavor == gcfRepRapFirmware);
 
     /* ! Freeze/Thaw in this function is needed to avoid call OnPaint() for erased pages
      * and be cause of application crash, when try to change Preset in moment,
@@ -2664,26 +2664,26 @@ void TabPrinter::build_unregular_pages(bool from_initial_build/* = false*/)
      *  */
     Freeze();
 
-    // Add/delete Kinematics page according to is_marlin_flavor
+    // Add/delete Kinematics page according to show_mach_limits
     size_t existed_page = 0;
     for (size_t i = n_before_extruders; i < m_pages.size(); ++i) // first make sure it's not there already
         if (m_pages[i]->title().find(L("Machine limits")) != std::string::npos) {
-            if (!is_marlin_flavor || m_rebuild_kinematics_page)
+            if (!show_mach_limits || m_rebuild_kinematics_page)
                 m_pages.erase(m_pages.begin() + i);
             else
                 existed_page = i;
             break;
         }
 
-    if (existed_page < n_before_extruders && (is_marlin_flavor || from_initial_build)) {
+    if (existed_page < n_before_extruders && (show_mach_limits || from_initial_build)) {
         auto page = build_kinematics_page();
-        if (from_initial_build && !is_marlin_flavor)
+        if (from_initial_build && !show_mach_limits)
             page->clear();
         else
             m_pages.insert(m_pages.begin() + n_before_extruders, page);
     }
 
-    if (is_marlin_flavor)
+    if (show_mach_limits)
         n_before_extruders++;
     size_t		n_after_single_extruder_MM = 2; //	Count of pages after single_extruder_multi_material page
 
@@ -2928,7 +2928,7 @@ void TabPrinter::toggle_options()
         toggle_option("single_extruder_multi_material", have_multiple_extruders);
 
         auto flavor = m_config->option<ConfigOptionEnum<GCodeFlavor>>("gcode_flavor")->value;
-        bool is_marlin_flavor = flavor == gcfMarlinLegacy || flavor == gcfMarlinFirmware || flavor == gcfRepRapFirmware;
+        bool is_marlin_flavor = flavor == gcfMarlinLegacy || flavor == gcfMarlinFirmware;
         // Disable silent mode for non-marlin firmwares.
         toggle_option("silent_mode", is_marlin_flavor);
     }