CURA-12833 improve bridge lines direction (#2266)

Author: HellAholic

CMakeLists.txt

@@ -65,6 +65,7 @@ set(engine_SRCS # Except main.cpp.
         src/multiVolumes.cpp
         src/path_ordering.cpp
         src/PathAdapter.cpp
+        src/PathOrderMonotonic.cpp
         src/Preheat.cpp
         src/PrimeTower/PrimeTower.cpp
         src/PrimeTower/PrimeTowerNormal.cpp
@@ -177,6 +178,7 @@ set(engine_SRCS # Except main.cpp.
         src/geometry/Point3LL.cpp
         src/geometry/Polygon.cpp
         src/geometry/Shape.cpp
+        src/geometry/PointMatrix.cpp
         src/geometry/PointsSet.cpp
         src/geometry/SingleShape.cpp
         src/geometry/PartsView.cpp

include/FffGcodeWriter.h

@@ -11,6 +11,7 @@
 #include "FanSpeedLayerTime.h"
 #include "GCodePathConfig.h"
 #include "LayerPlanBuffer.h"
+#include "LinesOrderingMethod.h"
 #include "gcodeExport.h"
 #include "utils/LayerVector.h"
 #include "utils/NoCopy.h"
@@ -591,6 +592,7 @@ class FffGcodeWriter : public NoCopy
      * minimise travel moves (``false``).
      * \param[out] added_something Whether this function added anything to the layer plan
      * \param fan_speed fan speed override for this skin area
+     * \param forced_small_area_width A specific value to be used for small_area_width when generating the infill, or nullopt to use the normal value
      */
     void processSkinPrintFeature(
         const SliceDataStorage& storage,
@@ -603,10 +605,11 @@ class FffGcodeWriter : public NoCopy
         const AngleDegrees skin_angle,
         const coord_t skin_overlap,
         const Ratio skin_density,
-        const bool monotonic,
+        const LinesOrderingMethod ordering,
         const bool is_roofing_flooring,
         bool& added_something,
-        double fan_speed = GCodePathConfig::FAN_SPEED_DEFAULT) const;
+        double fan_speed = GCodePathConfig::FAN_SPEED_DEFAULT,
+        std::optional<coord_t> forced_small_area_width = std::nullopt) const;
 
     /*!
      *  see if we can avoid printing a lines or zig zag style skin part in multiple segments by moving to

include/LayerPlan.h

@@ -785,7 +785,8 @@ class LayerPlan : public NoCopy
         const coord_t exclude_distance = 0,
         const coord_t wipe_dist = 0,
         const Ratio flow_ratio = 1.0_r,
-        const double fan_speed = GCodePathConfig::FAN_SPEED_DEFAULT);
+        const double fan_speed = GCodePathConfig::FAN_SPEED_DEFAULT,
+        const bool interlaced = false);
 
     /*!
      * Add a spiralized slice of wall that is interpolated in X/Y between \p last_wall and \p wall.

include/LinesOrderingMethod.h

@@ -0,0 +1,20 @@
+// Copyright (c) 2025 UltiMaker
+// CuraEngine is released under the terms of the AGPLv3 or higher
+
+#ifndef LINES_ORDERING_METHOD_H
+#define LINES_ORDERING_METHOD_H
+
+
+namespace cura
+{
+
+enum class LinesOrderingMethod
+{
+    Basic, // Lines are ordered by shortest distance
+    Monotonic, // Lines are ordered so that they will always form a continuous print along a direction
+    Interlaced, // Similar to monotonic, but with 2 passes so that adjacent lines will not be printed just after each other
+};
+
+} // namespace cura
+
+#endif

include/PathOrderMonotonic.h

@@ -4,20 +4,23 @@
 #ifndef BRIDGE_H
 #define BRIDGE_H
 
+#include <optional>
+
 namespace cura
 {
 
 class Shape;
-class Settings;
+class SliceMeshStorage;
 class SliceDataStorage;
 class SupportLayer;
+class AngleDegrees;
 
 /*!
  * \brief Computes the angle that lines have to take to bridge a certain shape
  * best.
  *
  * If the area should not be bridged, an angle of -1 is returned.
- * \param settings The settings container to get settings from.
+ * \param mesh The mesh being processed.
  * \param skin_outline The shape to fill with lines.
  * \param storage The slice data storage where to find objects that the bridge
  * could rest on in previous layers.
@@ -27,8 +30,8 @@ class SupportLayer;
  * \param supported_regions Pre-computed regions that the support layer would
  * support.
  */
-double bridgeAngle(
-    const Settings& settings,
+std::optional<AngleDegrees> bridgeAngle(
+    const SliceMeshStorage& mesh,
     const Shape& skin_outline,
     const SliceDataStorage& storage,
     const unsigned layer_nr,

include/bridge.h

@@ -68,6 +68,21 @@ class Point2D
         return Point2D(x_ * scale, y_ * scale);
     }
 
+    Point2D operator-(const Point2D& other) const
+    {
+        return Point2D(x_ - other.x_, y_ - other.y_);
+    }
+
+    Point2D operator+(const Point2D& other) const
+    {
+        return Point2D(x_ + other.x_, y_ + other.y_);
+    }
+
+    Point2D operator-() const
+    {
+        return Point2D(-x_, -y_);
+    }
+
     static double dot(const Point2D& p0, const Point2D& p1)
     {
         return p0.x_ * p1.x_ + p0.y_ * p1.y_;

include/geometry/Point2D.h

@@ -5,76 +5,41 @@
 #define GEOMETRY_POINT_MATRIX_H
 
 #include <array>
-#include <numbers>
 
 #include "geometry/Point2LL.h"
 
 
 namespace cura
 {
 
+class AngleDegrees;
+class AngleRadians;
+
 class PointMatrix
 {
 public:
     std::array<double, 4> matrix{ 1, 0, 0, 1 };
 
     PointMatrix() noexcept = default;
 
-    explicit PointMatrix(double rotation)
-    {
-        rotation = rotation / 180 * std::numbers::pi;
-        matrix.at(0) = std::cos(rotation);
-        matrix.at(1) = -std::sin(rotation);
-        matrix.at(2) = -matrix.at(1);
-        matrix.at(3) = matrix.at(0);
-    }
-
-    explicit PointMatrix(const Point2LL& p)
-    {
-        matrix.at(0) = static_cast<double>(p.X);
-        matrix.at(1) = static_cast<double>(p.Y);
-        double f = std::sqrt((matrix.at(0) * matrix.at(0)) + (matrix.at(1) * matrix.at(1)));
-        matrix.at(0) /= f;
-        matrix.at(1) /= f;
-        matrix.at(2) = -matrix.at(1);
-        matrix.at(3) = matrix.at(0);
-    }
-
-    static PointMatrix scale(double s)
-    {
-        PointMatrix ret;
-        ret.matrix.at(0) = s;
-        ret.matrix.at(3) = s;
-        return ret;
-    }
-
-    [[nodiscard]] Point2LL apply(const Point2LL& p) const
-    {
-        const auto x = static_cast<double>(p.X);
-        const auto y = static_cast<double>(p.Y);
-        return { std::llrint(x * matrix.at(0) + y * matrix.at(1)), std::llrint(x * matrix.at(2) + y * matrix.at(3)) };
-    }
+    explicit PointMatrix(double rotation);
+
+    explicit PointMatrix(const AngleDegrees& rotation);
+
+    explicit PointMatrix(const AngleRadians& rotation);
+
+    explicit PointMatrix(const Point2LL& p);
+
+    static PointMatrix scale(double s);
+
+    [[nodiscard]] Point2LL apply(const Point2LL& p) const;
 
     /*!
      * \warning only works on a rotation matrix! Output is incorrect for other types of matrix
      */
-    [[nodiscard]] Point2LL unapply(const Point2LL& p) const
-    {
-        const auto x = static_cast<double>(p.X);
-        const auto y = static_cast<double>(p.Y);
-        return { std::llrint(x * matrix.at(0) + y * matrix.at(2)), std::llrint(x * matrix.at(1) + y * matrix.at(3)) };
-    }
-
-    [[nodiscard]] PointMatrix inverse() const
-    {
-        PointMatrix ret;
-        double det = matrix.at(0) * matrix.at(3) - matrix.at(1) * matrix.at(2);
-        ret.matrix.at(0) = matrix.at(3) / det;
-        ret.matrix.at(1) = -matrix.at(1) / det;
-        ret.matrix.at(2) = -matrix.at(2) / det;
-        ret.matrix.at(3) = matrix.at(0) / det;
-        return ret;
-    }
+    [[nodiscard]] Point2LL unapply(const Point2LL& p) const;
+
+    [[nodiscard]] PointMatrix inverse() const;
 };
 
 } // namespace cura

include/geometry/PointMatrix.h

@@ -214,6 +214,11 @@ class Infill
         const SliceMeshStorage* mesh = nullptr,
         const Shape& prevent_small_exposed_to_air = Shape());
 
+    coord_t getLineDistance() const
+    {
+        return line_distance_;
+    }
+
     /*!
      * Generate the wall toolpaths of an infill area. It will return the inner contour and set the inner-contour.
      * This function is called within the generate() function but can also be called stand-alone

include/infill.h

@@ -1,22 +1,19 @@
-//Copyright (c) 2020 Ultimaker B.V.
-//CuraEngine is released under the terms of the AGPLv3 or higher.
+// Copyright (c) 2020 Ultimaker B.V.
+// CuraEngine is released under the terms of the AGPLv3 or higher.
 
 #ifndef UTILS_HALF_EDGE_GRAPH_H
 #define UTILS_HALF_EDGE_GRAPH_H
 
 
-#include <list>
 #include <cassert>
-
-
+#include <list>
 
 #include "HalfEdge.h"
 #include "HalfEdgeNode.h"
-#include "SVG.h"
 
 namespace cura
 {
-    using namespace cura;
+using namespace cura;
 
 template<class node_data_t, class edge_data_t, class derived_node_t, class derived_edge_t> // types of data contained in nodes and edges
 class HalfEdgeGraph