Added simple autosetting of custom supports based on facet normal angle

src/slic3r/GUI/Gizmos/GLGizmoFdmSupports.cpp

@@ -523,6 +523,46 @@ void GLGizmoFdmSupports::update_vertex_buffers(const ModelVolume* mv,
 }
 
 
+void GLGizmoFdmSupports::select_facets_by_angle(float threshold_deg, bool overwrite, bool block)
+{
+    float threshold = (M_PI/180.)*threshold_deg;
+    const Selection& selection = m_parent.get_selection();
+    const ModelObject* mo = m_c->selection_info()->model_object();
+    const ModelInstance* mi = mo->instances[selection.get_instance_idx()];
+
+    int mesh_id = -1;
+    for (const ModelVolume* mv : mo->volumes) {
+        if (! mv->is_model_part())
+            continue;
+
+        ++mesh_id;
+
+        const Transform3d trafo_matrix = mi->get_matrix(true) * mv->get_matrix(true);
+        Vec3f down  = (trafo_matrix.inverse() * (-Vec3d::UnitZ())).cast<float>().normalized();
+        Vec3f limit = (trafo_matrix.inverse() * Vec3d(std::sin(threshold), 0, -std::cos(threshold))).cast<float>().normalized();
+
+        float dot_limit = limit.dot(down);
+
+        // Now calculate dot product of vert_direction and facets' normals.
+        int idx = -1;
+        for (const stl_facet& facet : mv->mesh().stl.facet_start) {
+            ++idx;
+            if (facet.normal.dot(down) > dot_limit && (overwrite || m_selected_facets[mesh_id][idx] == FacetSupportType::NONE))
+                m_selected_facets[mesh_id][idx] = block
+                        ? FacetSupportType::BLOCKER
+                        : FacetSupportType::ENFORCER;
+        }
+        update_vertex_buffers(mv, mesh_id, true, true);
+    }
+
+    Plater::TakeSnapshot(wxGetApp().plater(), block ? _L("Block supports by angle")
+                                                    : _L("Add supports by angle"));
+    update_model_object();
+    m_parent.set_as_dirty();
+    m_setting_angle = false;
+}
+
+
 void GLGizmoFdmSupports::on_render_input_window(float x, float y, float bottom_limit)
 {
     if (! m_c->selection_info()->model_object())
@@ -531,6 +571,8 @@ void GLGizmoFdmSupports::on_render_input_window(float x, float y, float bottom_l
     const float approx_height = m_imgui->scaled(18.0f);
     y = std::min(y, bottom_limit - approx_height);
     m_imgui->set_next_window_pos(x, y, ImGuiCond_Always);
+
+    if (! m_setting_angle) {
         m_imgui->begin(on_get_name(), ImGuiWindowFlags_NoMove | ImGuiWindowFlags_AlwaysAutoResize | ImGuiWindowFlags_NoCollapse);
 
         // First calculate width of all the texts that are could possibly be shown. We will decide set the dialog width based on that:
@@ -566,6 +608,12 @@ void GLGizmoFdmSupports::on_render_input_window(float x, float y, float bottom_l
 
         m_imgui->text("");
 
+        if (m_imgui->button("Autoset by angle...")) {
+            m_setting_angle = true;
+        }
+
+        ImGui::SameLine();
+
         if (m_imgui->button(m_desc.at("remove_all"))) {
             ModelObject* mo = m_c->selection_info()->model_object();
             int idx = -1;
@@ -618,9 +666,29 @@ void GLGizmoFdmSupports::on_render_input_window(float x, float y, float bottom_l
             ImGui::EndTooltip();
         }
 
-
-
         m_imgui->end();
+        if (m_setting_angle)
+            m_parent.set_as_dirty();
+    }
+    else {
+        std::string name = "Autoset custom supports";
+        m_imgui->begin(wxString(name), ImGuiWindowFlags_NoMove | ImGuiWindowFlags_AlwaysAutoResize | ImGuiWindowFlags_NoCollapse);
+        m_imgui->text("Threshold:");
+        ImGui::SameLine();
+        m_imgui->slider_float("", &m_angle_threshold_deg, 0.f, 90.f, "%.f");
+        m_imgui->checkbox(wxString("Overwrite already selected facets"), m_overwrite_selected);
+        if (m_imgui->button("Enforce"))
+            select_facets_by_angle(m_angle_threshold_deg, m_overwrite_selected, false);
+        ImGui::SameLine();
+        if (m_imgui->button("Block"))
+            select_facets_by_angle(m_angle_threshold_deg, m_overwrite_selected, true);
+        ImGui::SameLine();
+        if (m_imgui->button("Cancel"))
+            m_setting_angle = false;
+        m_imgui->end();
+        if (! m_setting_angle)
+            m_parent.set_as_dirty();
+    }
 }
 
 bool GLGizmoFdmSupports::on_is_activable() const
@@ -680,6 +748,7 @@ void GLGizmoFdmSupports::on_set_state()
     }
     if (m_state == Off && m_old_state != Off) { // the gizmo was just turned Off
         // we are actually shutting down
+        m_setting_angle = false;
         wxGetApp().plater()->leave_gizmos_stack();
         {
             Plater::TakeSnapshot snapshot(wxGetApp().plater(), _(L("FDM gizmo turned off")));

src/slic3r/GUI/Gizmos/GLGizmoFdmSupports.hpp

@@ -61,10 +61,15 @@ private:
     void update_model_object() const;
     void update_from_model_object();
 
+    void select_facets_by_angle(float threshold, bool overwrite, bool block);
+    bool m_overwrite_selected = false;
+    float m_angle_threshold_deg = 45.f;
+
     bool is_mesh_point_clipped(const Vec3d& point) const;
 
     float m_clipping_plane_distance = 0.f;
     std::unique_ptr<ClippingPlane> m_clipping_plane;
+    bool m_setting_angle = false;
 
     // This map holds all translated description texts, so they can be easily referenced during layout calculations
     // etc. When language changes, GUI is recreated and this class constructed again, so the change takes effect.