add infill pattern "Cross Hatch"

src/libslic3r/CMakeLists.txt

@@ -90,6 +90,8 @@ set(SLIC3R_SOURCES
     Fill/FillConcentric.hpp
     Fill/FillConcentricInternal.cpp
     Fill/FillConcentricInternal.hpp
+    Fill/FillCrossHatch.cpp
+    Fill/FillCrossHatch.hpp
     Fill/FillEnsuring.cpp
     Fill/FillEnsuring.hpp
     Fill/FillHoneycomb.cpp

src/libslic3r/Fill/FillBase.cpp

@@ -23,6 +23,8 @@
 #include "FillEnsuring.hpp"
 //w29
 #include "FillConcentricInternal.hpp"
+//w32
+#include "FillCrossHatch.hpp"
 
 #include <boost/log/trivial.hpp>
 
@@ -57,6 +59,8 @@ Fill* Fill::new_from_type(const InfillPattern type)
     //w14
     //w29
     case ipConcentricInternal:  return new FillConcentricInternal();
+    //w32
+    case ipCrossHatch:          return new FillCrossHatch();
     default: throw Slic3r::InvalidArgument("unknown type");
     }
 }

src/libslic3r/Fill/FillCrossHatch.cpp

@@ -0,0 +1,236 @@
+#include "../ClipperUtils.hpp"
+#include "../ShortestPath.hpp"
+#include "../Surface.hpp"
+
+#include "FillCrossHatch.hpp"
+
+namespace Slic3r {
+
+    // CrossHatch Infill: Enhances 3D Printing Speed & Reduces Noise
+    // CrossHatch, as its name hints, alternates line direction by 90 degrees every few layers to improve adhesion.
+    // It introduces transform layers between direction shifts for better line cohesion, which fixes the weakness of line infill.
+    // The transform technique is inspired by David Eccles, improved 3D honeycomb but also a more flexible implementation.
+    // This method notably increases printing speed, meeting the demands of modern high-speed 3D printers, and reduces noise for most layers.
+    // By Bambu Lab
+
+    // graph credits: David Eccles (gringer).
+    // But we made a different definition for points.
+    /*    o---o
+     *   /     \
+     *  /       \
+     *           \       /
+     *            \     /
+     *             o---o
+     *   p1   p2  p3   p4
+     *
+     *   // X1 = progress * (1/8) * period
+     *   // X2 = ( (1/2 - progress) * (1/8) ) * period
+     *   // X3 = X1 + (1/2) * period
+     *   // X4 = ( (1 - progress) * (1/8) ) * period
+     *   // Y1 = X1
+     *   // Y2 = X1
+     *   // Y3 = -X1
+     *   // Y4 = -X1
+     */
+
+    static Pointfs generate_one_cycle(double progress, coordf_t period)
+    {
+        Pointfs out;
+        double  offset = progress * 1. / 8. * period;
+        out.reserve(4);
+        out.push_back(Vec2d(0.25 * period - offset, offset));
+        out.push_back(Vec2d(0.25 * period + offset, offset));
+        out.push_back(Vec2d(0.75 * period - offset, -offset));
+        out.push_back(Vec2d(0.75 * period + offset, -offset));
+        return out;
+    }
+
+    static Polylines generate_transform_pattern(double inprogress, int direction, coordf_t ingrid_size, coordf_t inwidth, coordf_t inheight)
+    {
+        coordf_t  width = inwidth;
+        coordf_t  height = inheight;
+        coordf_t  grid_size = ingrid_size * 2; // we due with odd and even saparately.
+        double    progress = inprogress;
+        Polylines out_polylines;
+
+        // generate template patterns;
+        Pointfs one_cycle_points = generate_one_cycle(progress, grid_size);
+
+        Polyline one_cycle;
+        one_cycle.points.reserve(one_cycle_points.size());
+        for (size_t i = 0; i < one_cycle_points.size(); i++) one_cycle.points.push_back(Point(one_cycle_points[i]));
+
+        // swap if vertical
+        if (direction < 0) {
+            width = height;
+            height = inwidth;
+        }
+
+        // replicate polylines;
+        Polylines odd_polylines;
+        Polyline  odd_poly;
+        int       num_of_cycle = width / grid_size + 2;
+        odd_poly.points.reserve(num_of_cycle * one_cycle.size());
+
+        // replicate to odd line
+        Point translate = Point(0, 0);
+        for (size_t i = 0; i < num_of_cycle; i++) {
+            Polyline odd_points;
+            odd_points = Polyline(one_cycle);
+            odd_points.translate(Point(i * grid_size, 0.0));
+            odd_poly.points.insert(odd_poly.points.end(), odd_points.begin(), odd_points.end());
+        }
+
+        // fill the height
+        int num_of_lines = height / grid_size + 2;
+        odd_polylines.reserve(num_of_lines * odd_poly.size());
+        for (size_t i = 0; i < num_of_lines; i++) {
+            Polyline poly = odd_poly;
+            poly.translate(Point(0.0, grid_size * i));
+            odd_polylines.push_back(poly);
+        }
+        // save to output
+        out_polylines.insert(out_polylines.end(), odd_polylines.begin(), odd_polylines.end());
+
+        // replicate to even lines
+        Polylines even_polylines;
+        even_polylines.reserve(odd_polylines.size());
+        for (size_t i = 0; i < odd_polylines.size(); i++) {
+            Polyline even = odd_poly;
+            even.translate(Point(-0.5 * grid_size, (i + 0.5) * grid_size));
+            even_polylines.push_back(even);
+        }
+
+        // save for output
+        out_polylines.insert(out_polylines.end(), even_polylines.begin(), even_polylines.end());
+
+        // change to vertical if need
+        if (direction < 0) {
+            // swap xy, see if we need better performance method
+            for (Polyline& poly : out_polylines) {
+                for (Point& p : poly) { std::swap(p.x(), p.y()); }
+            }
+        }
+
+        return out_polylines;
+    }
+
+    static Polylines generate_repeat_pattern(int direction, coordf_t grid_size, coordf_t inwidth, coordf_t inheight)
+    {
+        coordf_t  width = inwidth;
+        coordf_t  height = inheight;
+        Polylines out_polylines;
+
+        // swap if vertical
+        if (direction < 0) {
+            width = height;
+            height = inwidth;
+        }
+
+        int num_of_lines = height / grid_size + 1;
+        out_polylines.reserve(num_of_lines);
+
+        for (int i = 0; i < num_of_lines; i++) {
+            Polyline poly;
+            poly.points.reserve(2);
+            poly.append(Point(coordf_t(0), coordf_t(grid_size * i)));
+            poly.append(Point(width, coordf_t(grid_size * i)));
+            out_polylines.push_back(poly);
+        }
+
+        // change to vertical if needed
+        if (direction < 0) {
+            // swap xy
+            for (Polyline& poly : out_polylines) {
+                for (Point& p : poly) { std::swap(p.x(), p.y()); }
+            }
+        }
+
+        return out_polylines;
+    }
+
+    // it makes the real patterns that overlap the bounding box
+    // repeat_ratio define the ratio between the height of repeat pattern and grid
+    static Polylines generate_infill_layers(coordf_t z_height, double repeat_ratio, coordf_t grid_size, coordf_t width, coordf_t height)
+    {
+        Polylines result;
+        coordf_t  trans_layer_size  = grid_size * 0.4;          // upper.
+        coordf_t  repeat_layer_size = grid_size * repeat_ratio; // lower.
+        z_height += repeat_layer_size / 2;                      // offset to improve first few layer strength
+        coordf_t period   = trans_layer_size + repeat_layer_size;
+        coordf_t remains  = z_height - std::floor(z_height / period) * period;
+        coordf_t trans_z  = remains - repeat_layer_size; // put repeat layer first.
+        coordf_t  repeat_z = remains;
+
+        int phase = fmod(z_height, period * 2) - (period - 1); // add epsilon
+        int direction = phase <= 0 ? -1 : 1;
+
+        // this is a repeat layer
+        if (trans_z < 0) {
+            result = generate_repeat_pattern(direction, grid_size, width, height);
+        }
+        // this is a transform layer
+        else {
+            double progress = fmod(trans_z, trans_layer_size) / trans_layer_size;
+
+            // split the progress to forward and backward, with a opposite direction.
+            if (progress < 0.5)
+                result = generate_transform_pattern((progress + 0.1) * 2, direction, grid_size, width, height); // increase overlapping.
+            else
+                result = generate_transform_pattern((1.1 - progress) * 2, -1 * direction, grid_size, width, height);
+        }
+
+        return result;
+    }
+
+    void FillCrossHatch::_fill_surface_single(
+        const FillParams& params, unsigned int thickness_layers, const std::pair<float, Point>& direction, ExPolygon expolygon, Polylines& polylines_out)
+    {
+        // rotate angle
+        auto infill_angle = float(this->angle);
+        if (std::abs(infill_angle) >= EPSILON) expolygon.rotate(-infill_angle);
+
+        // get the rotated bounding box
+        BoundingBox bb = expolygon.contour.bounding_box();
+
+        // linespace modifier
+        coord_t line_spacing = coord_t(scale_(this->spacing) / params.density);
+
+        // reduce density
+        if (params.density < 0.999) line_spacing *= 1.5;
+
+        bb.merge(align_to_grid(bb.min, Point(line_spacing * 4, line_spacing * 4)));
+
+        // generate pattern
+        Polylines polylines = generate_infill_layers(scale_(this->z), 1, line_spacing, bb.size()(0), bb.size()(1));
+
+        // shift the pattern to the actual space
+        for (Polyline& pl : polylines) { pl.translate(bb.min); }
+
+        polylines = intersection_pl(polylines, to_polygons(expolygon));
+
+        // --- remove small remains from gyroid infill
+        if (!polylines.empty()) {
+            // Remove very small bits, but be careful to not remove infill lines connecting thin walls!
+            // The infill perimeter lines should be separated by around a single infill line width.
+            const double minlength = scale_(0.8 * this->spacing);
+            polylines.erase(std::remove_if(polylines.begin(), polylines.end(), [minlength](const Polyline& pl)
+                { return pl.length() < minlength; }), polylines.end());
+        }
+
+        if (!polylines.empty()) {
+            int infill_start_idx = polylines_out.size(); // only rotate what belongs to us.
+            // connect lines
+            if (params.dont_connect() || polylines.size() <= 1)
+                append(polylines_out, chain_polylines(std::move(polylines)));
+            else
+                this->connect_infill(std::move(polylines), expolygon, polylines_out, this->spacing, params);
+
+            // rotate back
+            if (std::abs(infill_angle) >= EPSILON) {
+                for (auto it = polylines_out.begin() + infill_start_idx; it != polylines_out.end(); ++it) it->rotate(infill_angle);
+            }
+        }
+    }
+
+} // namespace Slic3r

src/libslic3r/Fill/FillCrossHatch.hpp

@@ -0,0 +1,28 @@
+#ifndef slic3r_FillCrossHatch_hpp_
+#define slic3r_FillCrossHatch_hpp_
+
+#include <map>
+
+#include "../libslic3r.h"
+
+#include "FillBase.hpp"
+
+namespace Slic3r {
+
+class FillCrossHatch : public Fill
+{
+public:
+    Fill *clone() const override { return new FillCrossHatch(*this); };
+    ~FillCrossHatch() override {}
+
+protected:
+    void _fill_surface_single(const FillParams &             params,
+                              unsigned int                   thickness_layers,
+                              const std::pair<float, Point> &direction,
+                              ExPolygon                      expolygon,
+                              Polylines &                    polylines_out) override;
+};
+
+} // namespace Slic3r
+
+#endif // slic3r_FillCrossHatch_hpp_

src/libslic3r/PrintConfig.cpp

@@ -120,7 +120,9 @@ static const t_config_enum_values s_keys_map_InfillPattern {
     { "supportcubic",       ipSupportCubic },
     { "lightning",          ipLightning },
         //w14
-    { "concentricInternal", ipConcentricInternal }
+    { "concentricInternal", ipConcentricInternal },
+    //w32
+    { "crosshatch",         ipCrossHatch}
 };
 CONFIG_OPTION_ENUM_DEFINE_STATIC_MAPS(InfillPattern)
 
@@ -1438,7 +1440,9 @@ void PrintConfigDef::init_fff_params()
         { "octagramspiral",     L("Octagram Spiral")},
         { "adaptivecubic",      L("Adaptive Cubic")},
         { "supportcubic",       L("Support Cubic")},
-        { "lightning",          L("Lightning")}
+        { "lightning",          L("Lightning")},
+        //w32
+        { "crosshatch",          L("Cross Hatch")}
     });
     def->set_default_value(new ConfigOptionEnum<InfillPattern>(ipStars));
 

src/libslic3r/PrintConfig.hpp

@@ -69,6 +69,8 @@ enum InfillPattern : int {
     ipCount,
     //w14
     ipConcentricInternal,
+    //w32
+    ipCrossHatch,
 };
 
 enum class IroningType {

src/libslic3r/PrintObject.cpp

@@ -2115,6 +2115,8 @@ void PrintObject::bridge_over_infill()
         switch (dominant_pattern) {
         case ipHilbertCurve: bridging_angle += 0.25 * PI; break;
         case ipOctagramSpiral: bridging_angle += (1.0 / 16.0) * PI; break;
+        //w32
+        case ipCrossHatch: return (bridging_angle + 45.0) * 2.0 * M_PI / 360.;
         default: break;
         }