SLA support points improvements

- semi-intelligent algorithm to place support points
- enhanced ImGui dialog with editing/non-editing mode
- support points can have different head diameter (only implemented in GUI so far)
- autogenerated points supporting emerging islands are annotated and the info is kept

src/libslic3r/SLA/SLASupportTree.hpp

@@ -34,6 +34,26 @@ enum class PillarConnectionMode {
     dynamic
 };
 
+struct SupportPoint {
+    Vec3f pos;
+    float head_front_radius;
+    bool is_new_island;
+
+    SupportPoint() :
+    pos(Vec3f::Zero()), head_front_radius(0.f), is_new_island(false) {}
+
+    SupportPoint(float pos_x, float pos_y, float pos_z, float head_radius, bool new_island) :
+    pos(pos_x, pos_y, pos_z), head_front_radius(head_radius), is_new_island(new_island) {}
+
+    SupportPoint(Vec3f position, float head_radius, bool new_island) :
+    pos(position), head_front_radius(head_radius), is_new_island(new_island) {}
+
+    SupportPoint(Eigen::Matrix<float, 5, 1, Eigen::DontAlign> data) :
+    pos(data(0), data(1), data(2)), head_front_radius(data(3)), is_new_island(data(4)) {}
+
+    bool operator==(const SupportPoint& sp) const { return (pos==sp.pos) && head_front_radius==sp.head_front_radius && is_new_island==sp.is_new_island; }
+};
+
 struct SupportConfig {
     // Radius in mm of the pointing side of the head.
     double head_front_radius_mm = 0.2;
@@ -118,7 +138,7 @@ EigenMesh3D to_eigenmesh(const TriangleMesh& m);
 EigenMesh3D to_eigenmesh(const ModelObject& model);
 
 // Simple conversion of 'vector of points' to an Eigen matrix
-PointSet    to_point_set(const std::vector<Vec3d>&);
+PointSet    to_point_set(const std::vector<sla::SupportPoint>&);
 
 
 /* ************************************************************************** */