allow users to adjust bottom infill flowrate

src/libslic3r/Preset.cpp

@@ -685,7 +685,7 @@ static std::vector<std::string> s_Preset_print_options {
      "initial_layer_infill_speed", "only_one_wall_top", "only_one_wall_first_layer",
      "timelapse_type",
      //SoftFever
-     "top_solid_infill_flow_ratio"
+     "top_solid_infill_flow_ratio","bottom_solid_infill_flow_ratio"
 
 };
 

src/libslic3r/PrintConfig.cpp

@@ -649,6 +649,16 @@ void PrintConfigDef::init_fff_params()
     def->max = 2;
     def->mode = comAdvanced;
     def->set_default_value(new ConfigOptionFloat(1));
+
+    def = this->add("bottom_solid_infill_flow_ratio", coFloat);
+    def->label = L("Bottom surface flow ratio");
+    def->category = L("Advanced");
+    def->tooltip = L("This factor affects the amount of material for bottom solid infill. ");
+    def->min = 0;
+    def->max = 2;
+    def->mode = comAdvanced;
+    def->set_default_value(new ConfigOptionFloat(1));
+
     
     def = this->add("only_one_wall_top", coBool);
     def->label = L("Only one wall on top surfaces");

src/libslic3r/PrintConfig.hpp

@@ -655,6 +655,7 @@ PRINT_CONFIG_CLASS_DEFINE(
     ((ConfigOptionFloat,                bridge_speed))
     ((ConfigOptionEnum<InfillPattern>,  top_surface_pattern))
     ((ConfigOptionFloat,                top_solid_infill_flow_ratio))
+    ((ConfigOptionFloat,                bottom_solid_infill_flow_ratio))
     ((ConfigOptionEnum<InfillPattern>,  bottom_surface_pattern))
     ((ConfigOptionFloat,                outer_wall_line_width))
     ((ConfigOptionFloat,                outer_wall_speed))

src/libslic3r/PrintRegion.cpp

@@ -25,8 +25,12 @@ Flow PrintRegion::flow(const PrintObject &object, FlowRole role, double layer_he
     double flow_ratio = 1.0;
     // Get extrusion width from configuration.
     // (might be an absolute value, or a percent value, or zero for auto)
-    if (first_layer && print_config.initial_layer_line_width.value > 0) {
+    if (first_layer) { 
-        config_width = print_config.initial_layer_line_width;
+        if(role != frExternalPerimeter)
+            flow_ratio = m_config.bottom_solid_infill_flow_ratio;
+        if(print_config.initial_layer_line_width.value > 0) {
+            config_width = print_config.initial_layer_line_width;
+        }
     } else if (role == frExternalPerimeter) {
         config_width = m_config.outer_wall_line_width;
     } else if (role == frPerimeter) {

src/slic3r/GUI/Tab.cpp

@@ -1783,6 +1783,7 @@ void TabPrint::build()
         optgroup->append_single_option_line("wall_infill_order");
         optgroup->append_single_option_line("bridge_flow");
         optgroup->append_single_option_line("top_solid_infill_flow_ratio");
+        optgroup->append_single_option_line("bottom_solid_infill_flow_ratio");
         optgroup->append_single_option_line("only_one_wall_top");
         optgroup->append_single_option_line("only_one_wall_first_layer");
         optgroup->append_single_option_line("detect_overhang_wall");