Added parameter "support_buildplate_only" for SLA supports.

src/libslic3r/PrintConfig.cpp

@@ -2566,6 +2566,14 @@ void PrintConfigDef::init_sla_params()
     def->enum_labels.push_back(L("Dynamic"));
     def->default_value = new ConfigOptionEnum<SLAPillarConnectionMode>(slapcmDynamic);
 
+    def = this->add("support_buildplate_only", coBool);
+    def->label = L("Support on build plate only");
+    def->category = L("Supports");
+    def->tooltip = L("Only create support if it lies on a build plate. Don't create support on a print.");
+    def->cli = "support-buildplate-only!";
+    def->mode = comSimple;
+    def->default_value = new ConfigOptionBool(false);
+
     def = this->add("support_pillar_widening_factor", coFloat);
     def->label = L("Pillar widening factor");
     def->category = L("Supports");

src/libslic3r/PrintConfig.hpp

@@ -976,6 +976,9 @@ public:
     // How the pillars are bridged together
     ConfigOptionEnum<SLAPillarConnectionMode> support_pillar_connection_mode;
 
+    // Generate only ground facing supports
+    ConfigOptionBool support_buildplate_only;
+
     // TODO: unimplemented at the moment. This coefficient will have an impact
     // when bridges and pillars are merged. The resulting pillar should be a bit
     // thicker than the ones merging into it. How much thicker? I don't know
@@ -1031,6 +1034,7 @@ protected:
         OPT_PTR(support_head_width);
         OPT_PTR(support_pillar_diameter);
         OPT_PTR(support_pillar_connection_mode);
+        OPT_PTR(support_buildplate_only);
         OPT_PTR(support_pillar_widening_factor);
         OPT_PTR(support_base_diameter);
         OPT_PTR(support_base_height);

src/libslic3r/SLA/SLASupportTree.cpp

@@ -1898,6 +1898,17 @@ bool SLASupportTree::generate(const PointSet &points,
     }
     };
 
+    if(cfg.ground_facing_only) { // Delete the non-gnd steps if necessary
+        program[ROUTING_NONGROUND] = []() {
+            BOOST_LOG_TRIVIAL(info) << "Skipping non-ground facing supports as "
+                                       "requested.";
+        };
+        program[HEADLESS]  = [](){
+            BOOST_LOG_TRIVIAL(info) << "Skipping headless stick generation as "
+                                       "requested";
+        };
+    }
+
     Steps pc = BEGIN, pc_prev = BEGIN;
 
     // Let's define a simple automaton that will run our program.

src/libslic3r/SLA/SLASupportTree.hpp

@@ -55,6 +55,9 @@ struct SupportConfig {
     // How to connect pillars
     PillarConnectionMode pillar_connection_mode = PillarConnectionMode::dynamic;
 
+    // Only generate pillars that can be routed to ground
+    bool ground_facing_only = false;
+
     // TODO: unimplemented at the moment. This coefficient will have an impact
     // when bridges and pillars are merged. The resulting pillar should be a bit
     // thicker than the ones merging into it. How much thicker? I don't know

src/libslic3r/SLAPrint.cpp

@@ -415,6 +415,7 @@ sla::SupportConfig make_support_cfg(const SLAPrintObjectConfig& c) {
     case slapcmDynamic:
         scfg.pillar_connection_mode = sla::PillarConnectionMode::dynamic; break;
     }
+    scfg.ground_facing_only = c.support_buildplate_only.getBool();
     scfg.pillar_widening_factor = c.support_pillar_widening_factor.getFloat();
     scfg.base_radius_mm = 0.5*c.support_base_diameter.getFloat();
     scfg.base_height_mm = c.support_base_height.getFloat();
@@ -1063,6 +1064,7 @@ bool SLAPrintObject::invalidate_state_by_config_options(const std::vector<t_conf
             || opt_key == "support_head_width"
             || opt_key == "support_pillar_diameter"
             || opt_key == "support_pillar_connection_mode"
+            || opt_key == "support_buildplate_only"
             || opt_key == "support_base_diameter"
             || opt_key == "support_base_height"
             || opt_key == "support_critical_angle"

src/slic3r/GUI/Preset.cpp

@@ -414,6 +414,7 @@ const std::vector<std::string>& Preset::sla_print_options()
             "support_head_width",
             "support_pillar_diameter",
             "support_pillar_connection_mode",
+            "support_buildplate_only",
             "support_pillar_widening_factor",
             "support_base_diameter",
             "support_base_height",

src/slic3r/GUI/Tab.cpp

@@ -3191,6 +3191,7 @@ void TabSLAPrint::build()
     optgroup = page->new_optgroup(_(L("Support pillar")));
     optgroup->append_single_option_line("support_pillar_diameter");
     optgroup->append_single_option_line("support_pillar_connection_mode");
+    optgroup->append_single_option_line("support_buildplate_only");
     optgroup->append_single_option_line("support_pillar_widening_factor");
     optgroup->append_single_option_line("support_base_diameter");
     optgroup->append_single_option_line("support_base_height");