CURA-9839 add bridging and overhang line type color scheme

Cura.proto

@@ -122,6 +122,7 @@ message PathSegment {
   bytes line_width = 5; // The widths of the line segments as bytes of a float array of length 1 or N
   bytes line_thickness = 6; // The thickness of the line segments as bytes of a float array of length 1 or N
   bytes line_feedrate = 7; // The feedrate of the line segments as bytes of a float array of length 1 or N
+  repeated uint32 attributes = 8; // Print attributes of each segment, e.g. overhanging or bridging
 }
 
 

include/FffGcodeWriter.h

@@ -600,6 +600,7 @@ class FffGcodeWriter : public NoCopy
      * \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
+     * \param print_attributes Print attributes to be set for this segment, e.g. overhanging or bridging
      */
     void processSkinPrintFeature(
         const SliceDataStorage& storage,
@@ -616,7 +617,8 @@ class FffGcodeWriter : public NoCopy
         const bool is_roofing_flooring,
         bool& added_something,
         double fan_speed = GCodePathConfig::FAN_SPEED_DEFAULT,
-        std::optional<coord_t> forced_small_area_width = std::nullopt) const;
+        std::optional<coord_t> forced_small_area_width = std::nullopt,
+        const PrintSegmentAttributes& print_attributes = {}) const;
 
     /*!
      *  see if we can avoid printing a lines or zig zag style skin part in multiple segments by moving to

include/InsetOrderOptimizer.h

@@ -6,6 +6,7 @@
 
 #include <unordered_set>
 
+#include "PrintSegmentAttributes.h"
 #include "settings/ZSeamConfig.h"
 #include "sliceDataStorage.h"
 
@@ -74,7 +75,7 @@ class InsetOrderOptimizer
      * \param retract_before_outer_wall The retraction behavior to be applied when moving to outer walls
      * \return Whether anything was added to the layer plan.
      */
-    bool addToLayer(const RetractBeforeOuterWall retract_before_outer_wall = RetractBeforeOuterWall::AUTOMATIC);
+    bool addToLayer(const RetractBeforeOuterWall retract_before_outer_wall = RetractBeforeOuterWall::AUTOMATIC, const PrintSegmentAttributes& print_attributes = {});
 
     /*!
      * Get the order constraints of the insets when printing walls per region / hole.

include/LayerPlan.h

@@ -192,6 +192,7 @@ class LayerPlan : public NoCopy
      * \param spiralize Whether to gradually increase the z while printing. (Note that this path may be part of a sequence of spiralized paths, forming one polygon)
      * \param speed_factor (optional) a factor which the speed will be multiplied by.
      * \param travel_to_z Indicates whether we should add a Z travel before the initial move of this path
+     * \param print_attributes Print attributes to be set for this segment, e.g. overhanging or bridging
      * \return A path with the given config which is now the last path in LayerPlan::paths
      */
     GCodePath* getLatestPathWithConfig(
@@ -202,7 +203,8 @@ class LayerPlan : public NoCopy
         const Ratio width_factor = 1.0_r,
         const bool spiralize = false,
         const Ratio speed_factor = 1.0_r,
-        const bool travel_to_z = true);
+        const bool travel_to_z = true,
+        const PrintSegmentAttributes print_attributes = {});
 
 public:
     /*!
@@ -446,6 +448,7 @@ class LayerPlan : public NoCopy
      * (Note that this path may be part of a sequence of spiralized paths,
      * forming one polygon.)
      * \param fan_speed Fan speed override for this path.
+     * \param print_attributes Print attributes to be set for this segment, e.g. overhanging or bridging
      */
     void addExtrusionMove(
         const Point3LL& p,
@@ -456,7 +459,8 @@ class LayerPlan : public NoCopy
         const bool spiralize = false,
         const Ratio speed_factor = 1.0_r,
         const double fan_speed = GCodePathConfig::FAN_SPEED_DEFAULT,
-        const bool travel_to_z = true);
+        const bool travel_to_z = true,
+        const PrintSegmentAttributes& print_attributes = {});
 
     void addExtrusionMoveWithGradualOverhang(
         const Point3LL& p,
@@ -467,7 +471,8 @@ class LayerPlan : public NoCopy
         const bool spiralize = false,
         const Ratio speed_factor = 1.0_r,
         const double fan_speed = GCodePathConfig::FAN_SPEED_DEFAULT,
-        const bool travel_to_z = true);
+        const bool travel_to_z = true,
+        const PrintSegmentAttributes& print_attributes = {});
 
     /*!
      * Adds an extrusion move that may go through a skin area
@@ -480,6 +485,7 @@ class LayerPlan : public NoCopy
      * @param width_factor The width factor to be used to extruder
      * @param spiralize Whether we are extruding using spiralize mode
      * @param travel_to_z Whether we should add a Z travel before starting the segment if necessary
+     * @param print_attributes Print attributes to be set for this segment, e.g. overhanging or bridging
      */
     void addSkinExtrusion(
         const Point3LL& p0,
@@ -490,7 +496,8 @@ class LayerPlan : public NoCopy
         const Ratio& flow,
         const Ratio& width_factor,
         const bool spiralize,
-        const bool travel_to_z);
+        const bool travel_to_z,
+        const PrintSegmentAttributes& print_attributes = {});
 
     /*!
      * Add polygon to the gcode starting at vertex \p startIdx
@@ -504,6 +511,7 @@ class LayerPlan : public NoCopy
      * \param force_retract Whether to force a retraction when moving to the start of the polygon (used for outer walls)
      * \param scarf_seam Indicates whether we may use a scarf seam for the path
      * \param smooth_speed Indicates whether we may use a speed gradient for the path
+     * \param print_attributes Print attributes to be set for this segment, e.g. overhanging or bridging
      */
     void addPolygon(
         const Polygon& polygon,
@@ -516,7 +524,8 @@ class LayerPlan : public NoCopy
         const Ratio& flow_ratio = 1.0_r,
         const ForceRetract force_retract = ForceRetract::AUTOMATIC,
         bool scarf_seam = false,
-        bool smooth_speed = false);
+        bool smooth_speed = false,
+        const PrintSegmentAttributes& print_attributes = {});
 
     /*!
      * Add polygons to the gcode with optimized order.
@@ -532,6 +541,7 @@ class LayerPlan : public NoCopy
      * \param polygons The polygons.
      * \param config The config with which to print the polygon lines.
      * for each given segment (optionally nullptr).
+     * \param print_attributes Print attributes to be set for this segment, e.g. overhanging or bridging
      * \param z_seam_config Optional configuration for z-seam.
      * \param wall_0_wipe_dist The distance to travel along each polygon after
      * it has been laid down, in order to wipe the start and end of the wall
@@ -553,6 +563,7 @@ class LayerPlan : public NoCopy
         const Shape& polygons,
         const GCodePathConfig& config,
         const Settings& settings,
+        const PrintSegmentAttributes& print_attributes = {},
         const ZSeamConfig& z_seam_config = ZSeamConfig(),
         coord_t wall_0_wipe_dist = 0,
         bool spiralize = false,
@@ -614,6 +625,7 @@ class LayerPlan : public NoCopy
      * a bridge line.
      * \param distance_to_bridge_start The distance along the wall from p0 to
      * the first bridge segment.
+     * \param print_attributes Print attributes to be set for this segment, e.g. overhanging or bridging
      */
     void addWallLine(
         const PathAdapter<ExtrusionLine>& wall,
@@ -632,7 +644,8 @@ class LayerPlan : public NoCopy
         double& non_bridge_line_volume,
         Ratio speed_factor,
         double distance_to_bridge_start,
-        const bool travel_to_z = true);
+        const bool travel_to_z = true,
+        const PrintSegmentAttributes& print_attributes = {});
 
     /*!
      * Add a wall to the g-code starting at vertex \p start_idx
@@ -687,6 +700,7 @@ class LayerPlan : public NoCopy
      * \param is_linked_path Whether the path is a continuation off the previous path
      * \param scarf_seam Indicates whether we may use a scarf seam for the path
      * \param smooth_speed Indicates whether we may use a speed gradient for the path
+     * \param print_attributes Print attributes to be set for this segment, e.g. overhanging or bridging
      */
     void addWall(
         const ExtrusionLine& wall,
@@ -703,7 +717,8 @@ class LayerPlan : public NoCopy
         const bool is_reversed,
         const bool is_linked_path,
         const bool scarf_seam = false,
-        const bool smooth_speed = false);
+        const bool smooth_speed = false,
+        const PrintSegmentAttributes& print_attributes = {});
 
     /*!
      * Add an infill wall to the g-code
@@ -752,6 +767,7 @@ class LayerPlan : public NoCopy
      * \param flow_ratio The ratio with which to multiply the extrusion amount
      * \param near_start_location Optional: Location near where to add the first line. If not provided the last position is used.
      * \param fan_speed optional fan speed override for this path
+     * \param print_attributes Print attributes to be set for this segment, e.g. overhanging or bridging
      * \param reverse_print_direction Whether to reverse the optimized order and their printing direction.
      * \param order_requirements Pairs where first needs to be printed before second. Pointers are pointing to elements of \p lines
      * \param extra_inwards_start_move_length The length of the extra inwards moves to be added at the start of each infill line
@@ -768,6 +784,7 @@ class LayerPlan : public NoCopy
         const Ratio flow_ratio = 1.0,
         const std::optional<Point2LL> near_start_location = std::optional<Point2LL>(),
         const double fan_speed = GCodePathConfig::FAN_SPEED_DEFAULT,
+        const PrintSegmentAttributes& print_attributes = {},
         const bool reverse_print_direction = false,
         const std::unordered_multimap<const Polyline*, const Polyline*>& order_requirements = PathOrderOptimizer<const Polyline*>::no_order_requirements_,
         const coord_t extra_inwards_start_move_length = 0,
@@ -819,6 +836,7 @@ class LayerPlan : public NoCopy
      * line.
      * \param flow_ratio The ratio with which to multiply the extrusion amount.
      * \param fan_speed Fan speed override for this path.
+     * \param print_attributes Print attributes to be set for this segment, e.g. overhanging or bridging
      */
     void addLinesMonotonic(
         const Shape& area,
@@ -831,7 +849,8 @@ class LayerPlan : public NoCopy
         const coord_t wipe_dist = 0,
         const Ratio flow_ratio = 1.0_r,
         const double fan_speed = GCodePathConfig::FAN_SPEED_DEFAULT,
-        const bool interlaced = false);
+        const bool interlaced = false,
+        const PrintSegmentAttributes& print_attributes = {});
 
     /*!
      * Add a spiralized slice of wall that is interpolated in X/Y between \p last_wall and \p wall.
@@ -956,6 +975,7 @@ class LayerPlan : public NoCopy
      * \param wipe_dist (optional) the distance wiped without extruding after laying down a line.
      * \param flow_ratio The ratio with which to multiply the extrusion amount
      * \param fan_speed optional fan speed override for this path
+     * \param print_attributes Print attributes to be set for this segment, e.g. overhanging or bridging
      * \param extra_inwards_start_move_length The length of the extra inwards moves to be added at the start of each infill line
      * \param extra_inwards_end_move_length The length of the extra inwards moves to be added at the end of each infill line
      * \param extra_inwards_move_contour The contour to be considered in order to add the inwards moves
@@ -967,6 +987,7 @@ class LayerPlan : public NoCopy
         const coord_t wipe_dist,
         const Ratio flow_ratio,
         const double fan_speed,
+        const PrintSegmentAttributes& print_attributes = {},
         const coord_t extra_inwards_start_move_length = 0,
         const coord_t extra_inwards_end_move_length = 0,
         const MendedShape& extra_inwards_move_contour = MendedShape());
@@ -992,6 +1013,7 @@ class LayerPlan : public NoCopy
      * \param reverse_order Adds polygons in reverse order.
      * \param scarf_seam Indicates whether we may use a scarf seam for the path
      * \param smooth_speed Indicates whether we may use a speed gradient for the path
+     * \param print_attributes Print attributes to be set for this segment, e.g. overhanging or bridging
      */
     void addPolygonsInGivenOrder(
         const std::vector<PathOrdering<const Polygon*>>& polygons,
@@ -1004,7 +1026,8 @@ class LayerPlan : public NoCopy
         const ForceRetract force_retract = ForceRetract::AUTOMATIC,
         bool reverse_order = false,
         bool scarf_seam = false,
-        bool smooth_speed = false);
+        bool smooth_speed = false,
+        const PrintSegmentAttributes& print_attributes = {});
 
     /*!
      *  @brief Send a GCodePath line to the communication object, applying proper Z offsets

include/PrintFeature.h

@@ -1,3 +1,6 @@
+// Copyright (c) 2026 UltiMaker
+// CuraEngine is released under the terms of the AGPLv3 or higher
+
 #ifndef PRINT_FEATURE
 #define PRINT_FEATURE
 

include/PrintSegmentAttributes.h

@@ -0,0 +1,32 @@
+// Copyright (c) 2026 UltiMaker
+// CuraEngine is released under the terms of the AGPLv3 or higher
+
+#ifndef PRINT_SEGMENT_FLAG
+#define PRINT_SEGMENT_FLAG
+
+#include <cstdint>
+
+#include "utils/Flags.h"
+
+namespace cura
+{
+
+/*!
+ * Print attributes are flags that can be added to some print segments to indicate that they have been processed a specific way,
+ * e.g. by using overhanging or bridging settings. They are used for display purposes.
+ * This enumeration has an equivalent in Cura/cura/PrintSegmentAttributes.py
+ */
+enum class PrintSegmentAttribute : uint8_t
+{
+    // clang-format off
+    None        = 0b00,
+    Overhanging = 0b01,
+    Bridging    = 0b10,
+    // clang-format on
+};
+
+using PrintSegmentAttributes = Flags<PrintSegmentAttribute>;
+
+} // namespace cura
+
+#endif

include/communication/ArcusCommunication.h

@@ -109,8 +109,15 @@ class ArcusCommunication : public Communication
      * \param line_width The width of the line.
      * \param line_thickness The thickness (in the Z direction) of the line.
      * \param velocity The velocity of printing this polygon.
-     */
-    void sendLineTo(const PrintFeatureType& type, const Point3LL& to, const coord_t& line_width, const coord_t& line_thickness, const Velocity& velocity) override;
+     * \param print_attributes Print attributes to be set for this segment, e.g. overhanging or bridging
+     */
+    void sendLineTo(
+        const PrintFeatureType& type,
+        const Point3LL& to,
+        const coord_t& line_width,
+        const coord_t& line_thickness,
+        const Velocity& velocity,
+        const PrintSegmentAttributes& print_attributes) override;
 
     /*
      * \brief Send the sliced layer data to the front-end after the optimisation

include/communication/CommandLine.h

@@ -81,7 +81,7 @@ class CommandLine : public Communication
      *
      * The command line doesn't show any layer view so this is ignored.
      */
-    void sendLineTo(const PrintFeatureType&, const Point3LL&, const coord_t&, const coord_t&, const Velocity&) override;
+    void sendLineTo(const PrintFeatureType&, const Point3LL&, const coord_t&, const coord_t&, const Velocity&, const PrintSegmentAttributes&) override;
 
     /*
      * \brief Complete a layer to show it in layer view.

include/communication/Communication.h

@@ -5,6 +5,7 @@
 #define COMMUNICATION_H
 
 #include "PrintInformation.h"
+#include "PrintSegmentAttributes.h"
 #include "geometry/Point2LL.h"
 #include "settings/types/LayerIndex.h"
 #include "settings/types/Velocity.h"
@@ -65,8 +66,16 @@ class Communication
      * \param line_width The width of the line.
      * \param line_thickness The thickness (in the Z direction) of the line.
      * \param velocity The velocity of printing this polygon.
+     * \param print_attributes Print attributes to be set for this segment, e.g. overhanging or bridging
      */
-    virtual void sendLineTo(const PrintFeatureType& type, const Point3LL& to, const coord_t& line_width, const coord_t& line_thickness, const Velocity& velocity) = 0;
+    virtual void sendLineTo(
+        const PrintFeatureType& type,
+        const Point3LL& to,
+        const coord_t& line_width,
+        const coord_t& line_thickness,
+        const Velocity& velocity,
+        const PrintSegmentAttributes& print_attributes = {})
+        = 0;
 
     /*
      * \brief Send the current position to visualise.

include/pathPlanning/GCodePath.h

@@ -8,6 +8,7 @@
 #include <vector>
 
 #include "GCodePathConfig.h"
+#include "PrintSegmentAttributes.h"
 #include "SpaceFillType.h"
 #include "TimeMaterialEstimates.h"
 #include "geometry/Point2LL.h"
@@ -50,6 +51,7 @@ struct GCodePath
     double fan_speed{ GCodePathConfig::FAN_SPEED_DEFAULT }; //!< fan speed override for this path, value should be within range 0-100 (inclusive) and ignored otherwise
     TimeMaterialEstimates estimates{}; //!< Naive time and material estimates
     bool travel_to_z{ true }; //! Indicates whether we should add a travel move to the Z height of the first point before processing the path
+    PrintSegmentAttributes print_attributes; //! Indicates if the line is processed with specific settings, e.g. overhanging or bridging
 
     /*!
      * Whether this config is the config of a travel path.