Initial port of Arachne from Cura.

src/libslic3r/Arachne/BeadingStrategy/DistributedBeadingStrategy.hpp

@@ -0,0 +1,48 @@
+// Copyright (c) 2021 Ultimaker B.V.
+// CuraEngine is released under the terms of the AGPLv3 or higher.
+
+#ifndef DISTRIBUTED_BEADING_STRATEGY_H
+#define DISTRIBUTED_BEADING_STRATEGY_H
+
+#include "BeadingStrategy.hpp"
+
+namespace Slic3r::Arachne
+{
+
+/*!
+ * This beading strategy chooses a wall count that would make the line width
+ * deviate the least from the optimal line width, and then distributes the lines
+ * evenly among the thickness available.
+ */
+class DistributedBeadingStrategy : public BeadingStrategy
+{
+protected:
+     // For uneven numbers of lines: Minimum factor of the optimal width for which the middle line will be split into two lines.
+    double wall_split_middle_threshold;
+    
+    // For even numbers of lines: Minimum factor of the optimal width for which a new middle line will be added between the two innermost lines.
+    double wall_add_middle_threshold;
+
+    float one_over_distribution_radius_squared; // (1 / distribution_radius)^2
+
+public:
+    /*!
+    * \param distribution_radius the radius (in number of beads) over which to distribute the discrepancy between the feature size and the optimal thickness
+    */
+    DistributedBeadingStrategy( const coord_t optimal_width,
+                                const coord_t default_transition_length,
+                                const double transitioning_angle,
+                                const double wall_split_middle_threshold,
+                                const double wall_add_middle_threshold,
+                                const int distribution_radius);
+
+    virtual ~DistributedBeadingStrategy() override {}
+
+    Beading compute(coord_t thickness, coord_t bead_count) const override;
+    coord_t getOptimalThickness(coord_t bead_count) const override;
+    coord_t getTransitionThickness(coord_t lower_bead_count) const override;
+    coord_t getOptimalBeadCount(coord_t thickness) const override;
+};
+
+} // namespace Slic3r::Arachne
+#endif // DISTRIBUTED_BEADING_STRATEGY_H