Cubic infill.

xs/src/libslic3r/Fill/FillBase.cpp

@@ -25,6 +25,7 @@ Fill* Fill::new_from_type(const InfillPattern type)
     case ipLine:                return new FillLine();
     case ipGrid:                return new FillGrid2();
     case ipTriangles:           return new FillTriangles();
+    case ipCubic:               return new FillCubic();
 //  case ipGrid:                return new FillGrid();
     case ipArchimedeanChords:   return new FillArchimedeanChords();
     case ipHilbertCurve:        return new FillHilbertCurve();

xs/src/libslic3r/Fill/FillBase.hpp

@@ -39,7 +39,7 @@ class Fill
 public:
     // Index of the layer.
     size_t      layer_id;
-    // Height of the layer, in unscaled coordinates
+    // Z coordinate of the top print surface, in unscaled coordinates
     coordf_t    z;
     // in unscaled coordinates
     coordf_t    spacing;

xs/src/libslic3r/Fill/FillRectilinear2.cpp

@@ -751,7 +751,7 @@ enum DirectionMask
     DIR_BACKWARD = 2
 };
 
-bool FillRectilinear2::fill_surface_by_lines(const Surface *surface, const FillParams &params, float angleBase, Polylines &polylines_out)
+bool FillRectilinear2::fill_surface_by_lines(const Surface *surface, const FillParams &params, float angleBase, float pattern_shift, Polylines &polylines_out)
 {
     // At the end, only the new polylines will be rotated back.
     size_t n_polylines_out_initial = polylines_out.size();
@@ -791,10 +791,14 @@ bool FillRectilinear2::fill_surface_by_lines(const Surface *surface, const FillP
     } else {
         // extend bounding box so that our pattern will be aligned with other layers
         // Transform the reference point to the rotated coordinate system.
+        Point refpt = rotate_vector.second.rotated(- rotate_vector.first);
+        // _align_to_grid will not work correctly with positive pattern_shift.
+        coord_t pattern_shift_scaled = coord_t(scale_(pattern_shift)) % this->_line_spacing;
+        refpt.x -= (pattern_shift_scaled > 0) ? pattern_shift_scaled : (this->_line_spacing + pattern_shift_scaled);
         bounding_box.merge(_align_to_grid(
             bounding_box.min, 
             Point(this->_line_spacing, this->_line_spacing), 
-            rotate_vector.second.rotated(- rotate_vector.first)));
+            refpt));
     }
 
     // Intersect a set of euqally spaced vertical lines wiht expolygon.
@@ -1438,7 +1442,7 @@ bool FillRectilinear2::fill_surface_by_lines(const Surface *surface, const FillP
 Polylines FillRectilinear2::fill_surface(const Surface *surface, const FillParams &params)
 {
     Polylines polylines_out;
-    if (! fill_surface_by_lines(surface, params, 0.f, polylines_out)) {
+    if (! fill_surface_by_lines(surface, params, 0.f, 0.f, polylines_out)) {
         printf("FillRectilinear2::fill_surface() failed to fill a region.\n");
     }
     return polylines_out;
@@ -1447,8 +1451,8 @@ Polylines FillRectilinear2::fill_surface(const Surface *surface, const FillParam
 Polylines FillGrid2::fill_surface(const Surface *surface, const FillParams &params)
 {
     Polylines polylines_out;
-    if (! fill_surface_by_lines(surface, params, 0.f, polylines_out) ||
+    if (! fill_surface_by_lines(surface, params, 0.f, 0.f, polylines_out) ||
-        ! fill_surface_by_lines(surface, params, float(M_PI / 2.), polylines_out)) {
+        ! fill_surface_by_lines(surface, params, float(M_PI / 2.), 0.f, polylines_out)) {
         printf("FillGrid2::fill_surface() failed to fill a region.\n");
     }
     return polylines_out;
@@ -1457,12 +1461,24 @@ Polylines FillGrid2::fill_surface(const Surface *surface, const FillParams &para
 Polylines FillTriangles::fill_surface(const Surface *surface, const FillParams &params)
 {
     Polylines polylines_out;
-    if (! fill_surface_by_lines(surface, params, 0.f, polylines_out) ||
+    if (! fill_surface_by_lines(surface, params, 0.f, 0., polylines_out) ||
-        ! fill_surface_by_lines(surface, params, float(M_PI / 3.), polylines_out) ||
+        ! fill_surface_by_lines(surface, params, float(M_PI / 3.), 0., polylines_out) ||
-        ! fill_surface_by_lines(surface, params, float(2. * M_PI / 3.), polylines_out)) {
+        ! fill_surface_by_lines(surface, params, float(2. * M_PI / 3.), 0., polylines_out)) {
         printf("FillTriangles::fill_surface() failed to fill a region.\n");
     }
     return polylines_out;
 }
 
+Polylines FillCubic::fill_surface(const Surface *surface, const FillParams &params)
+{
+    Polylines polylines_out;
+    if (! fill_surface_by_lines(surface, params, 0.f, z, polylines_out) ||
+        ! fill_surface_by_lines(surface, params, float(M_PI / 3.), -z, polylines_out) ||
+        // Rotated by PI*2/3 + PI to achieve reverse sloping wall.
+        ! fill_surface_by_lines(surface, params, float(M_PI * 2. / 3.), z, polylines_out)) {
+        printf("FillCubic::fill_surface() failed to fill a region.\n");
+    } 
+    return polylines_out; 
+}
+
 } // namespace Slic3r

xs/src/libslic3r/Fill/FillRectilinear2.hpp

@@ -16,7 +16,7 @@ public:
     virtual Polylines fill_surface(const Surface *surface, const FillParams &params);
 
 protected:
-	bool fill_surface_by_lines(const Surface *surface, const FillParams &params, float angleBase, Polylines &polylines_out);
+	bool fill_surface_by_lines(const Surface *surface, const FillParams &params, float angleBase, float pattern_shift, Polylines &polylines_out);
 
 	coord_t _min_spacing;
 	coord_t _line_spacing;
@@ -46,6 +46,18 @@ protected:
     virtual float _layer_angle(size_t idx) const { return 0.f; }
 };
 
+class FillCubic : public FillRectilinear2
+{
+public:
+    virtual ~FillCubic() {}
+    virtual Polylines fill_surface(const Surface *surface, const FillParams &params);
+
+protected:
+	// The grid fill will keep the angle constant between the layers, see the implementation of Slic3r::Fill::Base.
+    virtual float _layer_angle(size_t idx) const { return 0.f; }
+};
+
+
 }; // namespace Slic3r
 
 #endif // slic3r_FillRectilinear2_hpp_

xs/src/libslic3r/PrintConfig.cpp

@@ -372,6 +372,7 @@ PrintConfigDef::PrintConfigDef()
     def->enum_values.push_back("rectilinear");
     def->enum_values.push_back("grid");
     def->enum_values.push_back("triangles");
+    def->enum_values.push_back("cubic");
     def->enum_values.push_back("line");
     def->enum_values.push_back("concentric");
     def->enum_values.push_back("honeycomb");
@@ -382,6 +383,7 @@ PrintConfigDef::PrintConfigDef()
     def->enum_labels.push_back("Rectilinear");
     def->enum_labels.push_back("Grid");
     def->enum_labels.push_back("Triangles");
+    def->enum_labels.push_back("Cubic");
     def->enum_labels.push_back("Line");
     def->enum_labels.push_back("Concentric");
     def->enum_labels.push_back("Honeycomb");

xs/src/libslic3r/PrintConfig.hpp

@@ -30,7 +30,7 @@ enum GCodeFlavor {
 };
 
 enum InfillPattern {
-    ipRectilinear, ipGrid, ipTriangles, ipLine, ipConcentric, ipHoneycomb, ip3DHoneycomb,
+    ipRectilinear, ipGrid, ipTriangles, ipCubic, ipLine, ipConcentric, ipHoneycomb, ip3DHoneycomb,
     ipHilbertCurve, ipArchimedeanChords, ipOctagramSpiral,
 };
 
@@ -59,6 +59,7 @@ template<> inline t_config_enum_values ConfigOptionEnum<InfillPattern>::get_enum
     keys_map["rectilinear"]         = ipRectilinear;
     keys_map["grid"]                = ipGrid;
     keys_map["triangles"]           = ipTriangles;
+    keys_map["cubic"]               = ipCubic;
     keys_map["line"]                = ipLine;
     keys_map["concentric"]          = ipConcentric;
     keys_map["honeycomb"]           = ipHoneycomb;