CURA-12164 Fix innerwall seam position

include/InsetOrderOptimizer.h

@@ -59,7 +59,8 @@ class InsetOrderOptimizer
         const Point2LL& model_center_point,
         const Shape& disallowed_areas_for_seams = {},
         const bool scarf_seam = false,
-        const bool smooth_speed = false);
+        const bool smooth_speed = false,
+        const Shape& overhang_areas = Shape());
 
     /*!
      * Adds the insets to the given layer plan.
@@ -114,6 +115,7 @@ class InsetOrderOptimizer
     Shape disallowed_areas_for_seams_;
     const bool scarf_seam_;
     const bool smooth_speed_;
+    Shape overhang_areas_;
 
     std::vector<std::vector<const Polygon*>> inset_polys_; // vector of vectors holding the inset polygons
     Shape retraction_region_; // After printing an outer wall, move into this region so that retractions do not leave visible blobs. Calculated lazily if needed (see
@@ -128,7 +130,7 @@ class InsetOrderOptimizer
      *
      * \param closed_line The polygon to insert the seam point in. (It's assumed to be closed at least.)
      *
-     * \return The index of the inserted seam point, or std::nullopt if no seam point was inserted.
+     * \return The index of the inserted seam point, or the index of the closest point if an existing one can be used.
      */
     std::optional<size_t> insertSeamPoint(ExtrusionLine& closed_line);
 

include/LayerPlan.h

@@ -298,6 +298,11 @@ class LayerPlan : public NoCopy
      */
     void setSeamOverhangMask(const Shape& polys);
 
+    /*!
+     * Get the areas that are considered having air below, which is a union between bridge and overhang masks
+     */
+    Shape getAirBelowMask() const;
+
     /*!
      * Set roofing_mask.
      *
@@ -677,50 +682,6 @@ class LayerPlan : public NoCopy
         const bool is_top_layer,
         const bool is_bottom_layer);
 
-
-    /*!
-     * Given a wall polygon and a start vertex index, return the index of the first vertex that is supported (is not above air)
-     *
-     * Uses bridge_wall_mask and overhang_mask to determine where there is air below
-     *
-     * \param wall The wall polygon
-     * \param start_idx The index of the starting vertex of \p wall
-     * \return The index of the first supported vertex - if no vertices are supported, start_idx is returned
-     */
-    template<typename T>
-    size_t locateFirstSupportedVertex(const T& wall, const size_t start_idx) const
-    {
-        if (bridge_wall_mask_.empty() && seam_overhang_mask_.empty())
-        {
-            return start_idx;
-        }
-
-        const auto air_below = bridge_wall_mask_.unionPolygons(seam_overhang_mask_);
-
-        size_t curr_idx = start_idx;
-
-        while (true)
-        {
-            const Point2LL& vertex = cura::make_point(wall[curr_idx]);
-            if (! air_below.inside(vertex, true))
-            {
-                // vertex isn't above air so it's OK to use
-                return curr_idx;
-            }
-
-            if (++curr_idx >= wall.size())
-            {
-                curr_idx = 0;
-            }
-
-            if (curr_idx == start_idx)
-            {
-                // no vertices are supported so just return the original index
-                return start_idx;
-            }
-        }
-    }
-
     /*!
      * Write the planned paths to gcode
      *

include/path_ordering.h

@@ -82,6 +82,16 @@ struct PathOrdering
      */
     std::optional<size_t> force_start_index_;
 
+    /*!
+     * The start point calculation strategy to be used for this path
+     */
+    ZSeamConfig seam_config_;
+
+    /*!
+     * Indicates whether this path is an outer (or inner) wall
+     */
+    bool is_outer_wall{ false };
+
     /*!
      * Get vertex data from the custom path type.
      *

include/utils/AABB.h

@@ -9,6 +9,7 @@
 namespace cura
 {
 
+class PointsSet;
 class Polygon;
 class Shape;
 
@@ -21,10 +22,10 @@ class AABB
     AABB(); //!< initializes with invalid min and max
     AABB(const Point2LL& min, const Point2LL& max); //!< initializes with given min and max
     AABB(const Shape& shape); //!< Computes the boundary box for the given shape
-    AABB(const Polygon& poly); //!< Computes the boundary box for the given polygons
+    AABB(const PointsSet& poly); //!< Computes the boundary box for the given polygons
 
     void calculate(const Shape& shape); //!< Calculates the aabb for the given shape (throws away old min and max data of this aabb)
-    void calculate(const Polygon& poly); //!< Calculates the aabb for the given polygon (throws away old min and max data of this aabb)
+    void calculate(const PointsSet& poly); //!< Calculates the aabb for the given polygon (throws away old min and max data of this aabb)
 
     /*!
      * Whether the bounding box contains the specified point.
@@ -80,7 +81,7 @@ class AABB
      */
     void include(const Point2LL& point);
 
-    void include(const Polygon& polygon);
+    void include(const PointsSet& polygon);
 
     /*!
      * \brief Includes the specified bounding box in the bounding box.

include/utils/CriterionScore.h

@@ -0,0 +1,31 @@
+// Copyright (c) 2024 Ultimaker B.V.
+// CuraEngine is released under the terms of the AGPLv3 or higher.
+
+#ifndef UTILS_CRITERION_SCORE_H
+#define UTILS_CRITERION_SCORE_H
+
+namespace cura
+{
+
+/*!
+ * This structure represents a score given by a single crtierion when calculating a global score to select a best
+ * candidate among a list with multiple criteria.
+ */
+struct CriterionScore
+{
+    /*!
+     * The score given by the criterion. To ensure a proper selection, this value must be contained in [0.0, 1.0] and
+     * the different given scores must be evenly distributed in this range.
+     */
+    double score{ 0.0 };
+
+    /*!
+     * The weight to be given when taking this score into the global score. A score that contributes "normally" to the
+     * global score should have a weight of 1.0, and others should be adjusted around this value, to give them more or
+     * less influence.
+     */
+    double weight{ 0.0 };
+};
+
+} // namespace cura
+#endif // UTILS_CRITERION_SCORE_H

include/utils/Score.h

@@ -0,0 +1,61 @@
+// Copyright (c) 2024 Ultimaker B.V.
+// CuraEngine is released under the terms of the AGPLv3 or higher.
+
+#ifndef UTILS_SCORE_H
+#define UTILS_SCORE_H
+
+#include <fmt/format.h>
+
+#include "CriterionScore.h"
+
+namespace cura
+{
+
+/*!
+ * This class represents a score to be calculated over different criteria, to select the best candidate among a list.
+ */
+class Score
+{
+private:
+    double value_{ 0.0 };
+
+public:
+    /*!
+     * Get the actual score value, should be used for debug purposes only
+     */
+    double getValue() const
+    {
+        return value_;
+    }
+
+    /*!
+     * Add the calculated score of an inidividual criterion to the global score, taking care of its weight
+     */
+    void operator+=(const CriterionScore& criterion_score)
+    {
+        value_ += criterion_score.score * criterion_score.weight;
+    }
+
+    /*!
+     * Comparison operators to allow selecting the best global score
+     */
+    auto operator<=>(const Score&) const = default;
+};
+
+} // namespace cura
+
+namespace fmt
+{
+
+template<>
+struct formatter<cura::Score> : formatter<std::string>
+{
+    auto format(const cura::Score& score, format_context& ctx)
+    {
+        return fmt::format_to(ctx.out(), "Score{{{}}}", score.getValue());
+    }
+};
+
+} // namespace fmt
+
+#endif // UTILS_SCORE_H

include/utils/math.h

@@ -108,5 +108,33 @@ template<utils::multipliable T>
     return (dividend + divisor - 1) / divisor;
 }
 
+/*!
+ * \brief Calculates the "inverse linear interpolation" of a value over a range, i.e. given a range [min, max] the
+ *        value "min" would give a result of 0.0 and the value "max" would give a result of 1.0, values in between will
+ *        be interpolated linearly.
+ * \note The returned value may be out of the [0.0, 1.0] range if the given value is outside the [min, max] range, it is
+ *       up to the caller to clamp the result if required
+ * \note The range_min value may be greater than the range_max, inverting the interpolation logic
+ */
+template<utils::numeric T>
+[[nodiscard]] inline double inverse_lerp(T range_min, T range_max, T value)
+{
+    if (range_min == range_max)
+    {
+        return 0.0;
+    }
+
+    return static_cast<double>(value - range_min) / (range_max - range_min);
+}
+
+/*!
+ * \brief Get a random floating point number in the range [0.0, 1.0]
+ */
+template<std::floating_point T>
+[[nodiscard]] inline T randf()
+{
+    return static_cast<T>(std::rand()) / static_cast<T>(RAND_MAX);
+}
+
 } // namespace cura
 #endif // UTILS_MATH_H

src/FffGcodeWriter.cpp

@@ -3148,7 +3148,8 @@ bool FffGcodeWriter::processInsets(
             mesh.bounding_box.flatten().getMiddle(),
             disallowed_areas_for_seams,
             scarf_seam,
-            smooth_speed);
+            smooth_speed,
+            gcode_layer.getAirBelowMask());
         added_something |= wall_orderer.addToLayer();
     }
     return added_something;

src/InsetOrderOptimizer.cpp

@@ -54,7 +54,8 @@ InsetOrderOptimizer::InsetOrderOptimizer(
     const Point2LL& model_center_point,
     const Shape& disallowed_areas_for_seams,
     const bool scarf_seam,
-    const bool smooth_speed)
+    const bool smooth_speed,
+    const Shape& overhang_areas)
     : gcode_writer_(gcode_writer)
     , storage_(storage)
     , gcode_layer_(gcode_layer)
@@ -78,6 +79,7 @@ InsetOrderOptimizer::InsetOrderOptimizer(
     , disallowed_areas_for_seams_{ disallowed_areas_for_seams }
     , scarf_seam_(scarf_seam)
     , smooth_speed_(smooth_speed)
+    , overhang_areas_(overhang_areas)
 {
 }
 
@@ -93,6 +95,7 @@ bool InsetOrderOptimizer::addToLayer()
     const bool current_extruder_is_wall_x = wall_x_extruder_nr_ == extruder_nr_;
 
     const bool reverse = shouldReversePath(use_one_extruder, current_extruder_is_wall_x, outer_to_inner);
+    const bool use_shortest_for_inner_walls = outer_to_inner;
     auto walls_to_be_added = getWallsToBeAdded(reverse, use_one_extruder);
 
     const auto order = pack_by_inset ? getInsetOrder(walls_to_be_added, outer_to_inner) : getRegionOrder(walls_to_be_added, outer_to_inner);
@@ -114,7 +117,9 @@ bool InsetOrderOptimizer::addToLayer()
         reverse,
         order,
         group_outer_walls,
-        disallowed_areas_for_seams_);
+        disallowed_areas_for_seams_,
+        use_shortest_for_inner_walls,
+        overhang_areas_);
 
     for (auto& line : walls_to_be_added)
     {
@@ -126,7 +131,7 @@ bool InsetOrderOptimizer::addToLayer()
                 // If the user indicated that we may deviate from the vertices for the seam, we can insert a seam point, if needed.
                 force_start = insertSeamPoint(line);
             }
-            order_optimizer.addPolygon(&line, force_start);
+            order_optimizer.addPolygon(&line, force_start, line.is_outer_wall());
         }
         else
         {
@@ -202,7 +207,7 @@ std::optional<size_t> InsetOrderOptimizer::insertSeamPoint(ExtrusionLine& closed
     Point2LL closest_point;
     size_t closest_junction_idx = 0;
     coord_t closest_distance_sqd = std::numeric_limits<coord_t>::max();
-    bool should_reclaculate_closest = false;
+    bool should_recalculate_closest = false;
     if (z_seam_config_.type_ == EZSeamType::USER_SPECIFIED)
     {
         // For user-defined seams you usually don't _actually_ want the _closest_ point, per-se,
@@ -248,24 +253,27 @@ std::optional<size_t> InsetOrderOptimizer::insertSeamPoint(ExtrusionLine& closed
                 closest_junction_idx = i;
             }
         }
-        should_reclaculate_closest = true;
+        should_recalculate_closest = true;
     }
 
     const auto& start_pt = closed_line.junctions_[closest_junction_idx];
     const auto& end_pt = closed_line.junctions_[(closest_junction_idx + 1) % closed_line.junctions_.size()];
-    if (should_reclaculate_closest)
+    if (should_recalculate_closest)
     {
         // In the second case (see above) the closest point hasn't actually been calculated yet,
         // since in that case we'de need the start and end points. So do that here.
         closest_point = LinearAlg2D::getClosestOnLineSegment(request_point, start_pt.p_, end_pt.p_);
     }
     constexpr coord_t smallest_dist_sqd = 25;
-    if (vSize2(closest_point - start_pt.p_) <= smallest_dist_sqd || vSize2(closest_point - end_pt.p_) <= smallest_dist_sqd)
+    if (vSize2(closest_point - start_pt.p_) <= smallest_dist_sqd)
     {
-        // Early out if the closest point is too close to the start or end point.
-        // NOTE: Maybe return the index here anyway, since this is the point the current caller would want to force the seam to.
-        //       However, then the index returned would have a caveat that it _can_ point to an already exisiting point then.
-        return std::nullopt;
+        // If the closest point is very close to the start point, just use it instead.
+        return closest_junction_idx;
+    }
+    if (vSize2(closest_point - end_pt.p_) <= smallest_dist_sqd)
+    {
+        // If the closest point is very close to the end point, just use it instead.
+        return (closest_junction_idx + 1) % closed_line.junctions_.size();
     }
 
     // NOTE: This could also be done on a single axis (skipping the implied sqrt), but figuring out which one and then using the right values became a bit messy/verbose.

src/LayerPlan.cpp

@@ -1328,11 +1328,6 @@ void LayerPlan::addWall(
     {
         return;
     }
-    if (is_closed)
-    {
-        // make sure wall start point is not above air!
-        start_idx = locateFirstSupportedVertex(wall, start_idx);
-    }
     const bool actual_scarf_seam = scarf_seam && is_closed;
 
     double non_bridge_line_volume = max_non_bridge_line_volume; // assume extruder is fully pressurised before first non-bridge line is output
@@ -3049,6 +3044,11 @@ void LayerPlan::setSeamOverhangMask(const Shape& polys)
     seam_overhang_mask_ = polys;
 }
 
+Shape LayerPlan::getAirBelowMask() const
+{
+    return bridge_wall_mask_.unionPolygons(seam_overhang_mask_);
+}
+
 void LayerPlan::setRoofingMask(const Shape& polys)
 {
     roofing_mask_ = polys;