ENH: Full re-write of spiral vase

Github: 2744

* Practically full re-write of spiral vase
- Adds transition out to prevent sharp edge at the top of spiral vase.
- Adds XY interpolation
- Adds option to turn XY interpolation on/off

* - Increasing E to 5 decimal digits (I observed uneven flow with less than that)
- Excluding all travel moves (I saw a bug where somehow we ended up with travel moves within the print so excluding all travel moves)

* - max_xy_smoothing is now configurable, default is 200% of nozzle_diameter
- fixed no-op travel moves in the middle of spiral that now show up as defects when Smooth Spiral is enabled!

* - Avoiding namespace pollution
- Fixing dist_XY == 0 bug

---------

Co-authored-by: Andrew Boktor <aboktor@microsoft.com>
Co-authored-by: SoftFever <softfeverever@gmail.com>
Change-Id: I4e982b6192f730037ff497389454313af3905e82

src/libslic3r/GCode.cpp

@@ -2456,10 +2456,16 @@ void GCode::process_layers(
                 return this->process_layer(print, layer.second, layer_tools, &layer == &layers_to_print.back(), &print_object_instances_ordering, size_t(-1));
             }
         });
-    const auto spiral_mode = tbb::make_filter<GCode::LayerResult, GCode::LayerResult>(slic3r_tbb_filtermode::serial_in_order,
-        [&spiral_mode = *this->m_spiral_vase.get()](GCode::LayerResult in) -> GCode::LayerResult {
+    if (m_spiral_vase) {
+        float nozzle_diameter  = EXTRUDER_CONFIG(nozzle_diameter);
+        float max_xy_smoothing = m_config.get_abs_value("spiral_mode_max_xy_smoothing", nozzle_diameter);
+        this->m_spiral_vase->set_max_xy_smoothing(max_xy_smoothing);
+    }
+    const auto spiral_mode = tbb::make_filter<GCode::LayerResult, GCode::LayerResult>(
+        slic3r_tbb_filtermode::serial_in_order, [&spiral_mode = *this->m_spiral_vase.get(), & layers_to_print](GCode::LayerResult in) -> GCode::LayerResult {
             spiral_mode.enable(in.spiral_vase_enable);
-            return { spiral_mode.process_layer(std::move(in.gcode)), in.layer_id, in.spiral_vase_enable, in.cooling_buffer_flush };
+            bool last_layer = in.layer_id == layers_to_print.size() - 1;
+            return { spiral_mode.process_layer(std::move(in.gcode), last_layer), in.layer_id, in.spiral_vase_enable, in.cooling_buffer_flush};
         });
     const auto cooling = tbb::make_filter<GCode::LayerResult, std::string>(slic3r_tbb_filtermode::serial_in_order,
         [&cooling_buffer = *this->m_cooling_buffer.get()](GCode::LayerResult in) -> std::string {
@@ -2504,10 +2510,16 @@ void GCode::process_layers(
                 return this->process_layer(print, { std::move(layer) }, tool_ordering.tools_for_layer(layer.print_z()), &layer == &layers_to_print.back(), nullptr, single_object_idx, prime_extruder);
             }
         });
-    const auto spiral_mode = tbb::make_filter<GCode::LayerResult, GCode::LayerResult>(slic3r_tbb_filtermode::serial_in_order,
-        [&spiral_mode = *this->m_spiral_vase.get()](GCode::LayerResult in)->GCode::LayerResult {
+    if (m_spiral_vase) {
+        float nozzle_diameter  = EXTRUDER_CONFIG(nozzle_diameter);
+        float max_xy_smoothing = m_config.get_abs_value("spiral_mode_max_xy_smoothing", nozzle_diameter);
+        this->m_spiral_vase->set_max_xy_smoothing(max_xy_smoothing);
+    }
+    const auto spiral_mode = tbb::make_filter<GCode::LayerResult, GCode::LayerResult>(
+        slic3r_tbb_filtermode::serial_in_order, [&spiral_mode = *this->m_spiral_vase.get(), &layers_to_print](GCode::LayerResult in) -> GCode::LayerResult {
             spiral_mode.enable(in.spiral_vase_enable);
-            return { spiral_mode.process_layer(std::move(in.gcode)), in.layer_id, in.spiral_vase_enable, in.cooling_buffer_flush };
+            bool last_layer = in.layer_id == layers_to_print.size() - 1;
+            return { spiral_mode.process_layer(std::move(in.gcode), last_layer), in.layer_id, in.spiral_vase_enable, in.cooling_buffer_flush };
         });
     const auto cooling = tbb::make_filter<GCode::LayerResult, std::string>(slic3r_tbb_filtermode::serial_in_order,
         [&cooling_buffer = *this->m_cooling_buffer.get()](GCode::LayerResult in)->std::string {

src/libslic3r/GCode/SpiralVase.cpp

@@ -1,10 +1,77 @@
 #include "SpiralVase.hpp"
 #include "GCode.hpp"
 #include <sstream>
+#include <cmath>
+#include <limits>
 
 namespace Slic3r {
 
-std::string SpiralVase::process_layer(const std::string &gcode)
+namespace SpiralVaseHelpers {
+/** == Smooth Spiral Helpers == */
+/** Distance between a and b */
+float distance(SpiralVase::SpiralPoint a, SpiralVase::SpiralPoint b) {
+    return sqrt(pow(a.x - b.x, 2) + pow(a.y - b.y, 2));
+}
+
+SpiralVase::SpiralPoint subtract(SpiralVase::SpiralPoint a, SpiralVase::SpiralPoint b)
+{
+    return SpiralVase::SpiralPoint(a.x - b.x, a.y - b.y);
+}
+
+SpiralVase::SpiralPoint add(SpiralVase::SpiralPoint a, SpiralVase::SpiralPoint b) {
+    return SpiralVase::SpiralPoint(a.x + b.x, a.y + b.y);
+}
+
+SpiralVase::SpiralPoint scale(SpiralVase::SpiralPoint a, float factor) {
+    return SpiralVase::SpiralPoint(a.x * factor, a.y * factor);
+}
+
+/** dot product */
+float dot(SpiralVase::SpiralPoint a, SpiralVase::SpiralPoint b) {
+    return a.x * b.x + a.y * b.y;
+}
+
+/** Find the point on line ab closes to point c */
+SpiralVase::SpiralPoint nearest_point_on_line(SpiralVase::SpiralPoint c, SpiralVase::SpiralPoint a, SpiralVase::SpiralPoint b, float& dist)
+{
+    SpiralVase::SpiralPoint ab = subtract(b, a);
+    SpiralVase::SpiralPoint ac = subtract(c, a);
+    float t = dot(ac, ab) / dot(ab, ab);
+    t = t > 1 ? 1 : t;
+    t = t < 0 ? 0 : t;
+    SpiralVase::SpiralPoint closest = SpiralVase::SpiralPoint(add(a, scale(ab, t)));
+    dist = distance(c, closest);
+    return closest;
+}
+
+/** Given a set of lines defined by points such as line[n] is the line from points[n] to points[n+1],
+ *  find the closest point to p that falls on any of the lines */
+SpiralVase::SpiralPoint nearest_point_on_lines(SpiralVase::SpiralPoint                               p,
+                                               std::shared_ptr<std::vector<SpiralVase::SpiralPoint>> points,
+                                               bool&                                                 found,
+                                               float&                                                dist)
+{
+    if (points->size() < 2) {
+        found = false;
+        return SpiralVase::SpiralPoint(0, 0);
+    }
+    float min = std::numeric_limits<float>::max();
+    SpiralVase::SpiralPoint closest(0, 0);
+    for (unsigned long i = 0; i < points->size() - 1; i++) {
+        float currentDist = 0;
+        SpiralVase::SpiralPoint current = nearest_point_on_line(p, points->at(i), points->at(i + 1), currentDist);
+        if (currentDist < min) {
+            min = currentDist;
+            closest = current;
+            found = true;
+        }
+    }
+    dist = min;
+    return closest;
+}
+} // namespace SpiralVase
+
+std::string SpiralVase::process_layer(const std::string &gcode, bool last_layer)
 {
     /*  This post-processor relies on several assumptions:
         - all layers are processed through it, including those that are not supposed
@@ -45,19 +112,29 @@ std::string SpiralVase::process_layer(const std::string &gcode)
             }
         });
     }
-    
+
     // Remove layer height from initial Z.
     z -= layer_height;
-    
+
+    std::shared_ptr<std::vector<SpiralVase::SpiralPoint>>  current_layer  = std::make_shared<std::vector<SpiralVase::SpiralPoint>>();
+    std::shared_ptr<std::vector<SpiralVase::SpiralPoint>> previous_layer = m_previous_layer;
+
+    bool smooth_spiral = m_smooth_spiral;
     std::string new_gcode;
+    std::string transition_gcode;
+    float max_xy_dist_for_smoothing = m_max_xy_smoothing;
     //FIXME Tapering of the transition layer only works reliably with relative extruder distances.
     // For absolute extruder distances it will be switched off.
     // Tapering the absolute extruder distances requires to process every extrusion value after the first transition
     // layer.
-    bool  transition = m_transition_layer && m_config.use_relative_e_distances.value;
-    float layer_height_factor = layer_height / total_layer_length;
+    bool  transition_in = m_transition_layer && m_config.use_relative_e_distances.value;
+    bool  transition_out = last_layer && m_config.use_relative_e_distances.value;
     float len = 0.f;
-    m_reader.parse_buffer(gcode, [&new_gcode, &z, total_layer_length, layer_height_factor, transition, &len]
+    //set initial point
+    SpiralVase::SpiralPoint last_point = previous_layer != NULL && previous_layer->size() > 0 ? previous_layer->at(previous_layer->size()-1): SpiralVase::SpiralPoint(0,0);
+
+    m_reader.parse_buffer(gcode, [&new_gcode, &z, total_layer_length, layer_height, transition_in, &len, &current_layer, &previous_layer, &transition_gcode, transition_out,
+                                  smooth_spiral, &max_xy_dist_for_smoothing, &last_point]
         (GCodeReader &reader, GCodeReader::GCodeLine line) {
         if (line.cmd_is("G1")) {
             if (line.has_z()) {
@@ -69,29 +146,67 @@ std::string SpiralVase::process_layer(const std::string &gcode)
             } else {
                 float dist_XY = line.dist_XY(reader);
                 if (dist_XY > 0) {
-                    // horizontal move
-                    if (line.extruding(reader)) {
+                    if (line.extruding(reader)) { // Exclude wipe and retract
                         len += dist_XY;
-                        line.set(reader, Z, z + len * layer_height_factor);
-                        if (transition && line.has(E))
-                            // Transition layer, modulate the amount of extrusion from zero to the final value.
-                            line.set(reader, E, line.value(E) * len / total_layer_length);
+                        float factor = len / total_layer_length;
+                        if (transition_in)
+                            // Transition layer, interpolate the amount of extrusion from zero to the final value.
+                            line.set(reader, E, line.e() * factor, 5 /*decimal_digits*/);
+                        else if (transition_out) {
+                            // We want the last layer to ramp down extrusion, but without changing z height!
+                            // So clone the line before we mess with its Z and duplicate it into a new layer that ramps down E
+                            // We add this new layer at the very end
+                            GCodeReader::GCodeLine transitionLine(line);
+                            transitionLine.set(reader, E, line.e() * (1 - factor), 5 /*decimal_digits*/);
+                            transition_gcode += transitionLine.raw() + '\n';
+                        }
+                        // This line is the core of Spiral Vase mode, ramp up the Z smoothly
+                        line.set(reader, Z, z + factor * layer_height);
+                        if (smooth_spiral) {
+                            // Now we also need to try to interpolate X and Y
+                            SpiralVase::SpiralPoint p(line.x(), line.y()); // Get current x/y coordinates
+                            current_layer->push_back(p); // Store that point for later use on the next layer
+                            if (previous_layer != NULL) {
+                                bool found = false;
+                                float dist = 0;
+                                SpiralVase::SpiralPoint nearestp = SpiralVaseHelpers::nearest_point_on_lines(p, previous_layer, found, dist);
+                                if (found && dist < max_xy_dist_for_smoothing) {
+                                    // Interpolate between the point on this layer and the point on the previous layer
+                                    SpiralVase::SpiralPoint target = SpiralVaseHelpers::add(SpiralVaseHelpers::scale(nearestp, 1 - factor), SpiralVaseHelpers::scale(p, factor));
+                                    line.set(reader, X, target.x);
+                                    line.set(reader, Y, target.y);
+                                    // We need to figure out the distance of this new line!
+                                    float modified_dist_XY = SpiralVaseHelpers::distance(last_point, target);
+                                    // Scale the extrusion amount according to change in length
+                                    line.set(reader, E, line.e() * modified_dist_XY / dist_XY, 5 /*decimal_digits*/);
+                                    last_point = target;
+                                } else {
+                                    last_point = p;
+                                }
+                            }
+                        }
                         new_gcode += line.raw() + '\n';
                     }
                     return;
-                
                     /*  Skip travel moves: the move to first perimeter point will
                         cause a visible seam when loops are not aligned in XY; by skipping
                         it we blend the first loop move in the XY plane (although the smoothness
                         of such blend depend on how long the first segment is; maybe we should
-                        enforce some minimum length?).  */
+                        enforce some minimum length?).
+                        When smooth_spiral is enabled, we're gonna end up exactly where the next layer should
+                        start anyway, so we don't need the travel move */
                 }
             }
         }
         new_gcode += line.raw() + '\n';
+        if(transition_out) {
+            transition_gcode += line.raw() + '\n';
+        }
     });
-    
-    return new_gcode;
+
+    m_previous_layer = current_layer;
+
+    return new_gcode + transition_gcode;
 }
 
 }

src/libslic3r/GCode/SpiralVase.hpp

@@ -6,14 +6,25 @@
 
 namespace Slic3r {
 
-class SpiralVase {
+class SpiralVase
+{
 public:
+    class SpiralPoint
+    {
+    public:
+        SpiralPoint(float paramx, float paramy) : x(paramx), y(paramy) {}
+
+    public:
+        float x, y;
+    };
     SpiralVase(const PrintConfig &config) : m_config(config)
     {
         //BBS
         //m_reader.z() = (float)m_config.z_offset;
         m_reader.z() = 0.0f;
         m_reader.apply_config(m_config);
+        m_previous_layer = NULL;
+        m_smooth_spiral = config.spiral_mode_smooth;
     };
 
     void 		enable(bool en) {
@@ -21,17 +32,22 @@ public:
     	m_enabled 		   = en;
     }
 
-    std::string process_layer(const std::string &gcode);
-    
+    std::string process_layer(const std::string &gcode, bool last_layer);
+    void set_max_xy_smoothing(float max) {
+        m_max_xy_smoothing = max;
+    }
 private:
     const PrintConfig  &m_config;
     GCodeReader 		m_reader;
+    float               m_max_xy_smoothing = 0.f;
 
     bool 				m_enabled = false;
     // First spiral vase layer. Layer height has to be ramped up from zero to the target layer height.
     bool 				m_transition_layer = false;
+    // Whether to interpolate XY coordinates with the previous layer. Results in no seam at layer changes
+    bool                m_smooth_spiral = false;
+    std::shared_ptr<std::vector<SpiralPoint>> m_previous_layer;
 };
-
 }
 
 #endif // slic3r_SpiralVase_hpp_

src/libslic3r/Preset.cpp

@@ -792,7 +792,7 @@ bool Preset::has_cali_lines(PresetBundle* preset_bundle)
 }
 
 static std::vector<std::string> s_Preset_print_options {
-    "layer_height", "initial_layer_print_height", "wall_loops", "slice_closing_radius", "spiral_mode", "slicing_mode",
+    "layer_height", "initial_layer_print_height", "wall_loops", "slice_closing_radius", "spiral_mode", "spiral_mode_smooth", "spiral_mode_max_xy_smoothing", "slicing_mode",
     "top_shell_layers", "top_shell_thickness", "bottom_shell_layers", "bottom_shell_thickness",
     "ensure_vertical_shell_thickness", "reduce_crossing_wall", "detect_thin_wall", "detect_overhang_wall",
     "seam_position", "wall_sequence", "is_infill_first", "sparse_infill_density", "sparse_infill_pattern", "sparse_infill_anchor", "sparse_infill_anchor_max",

src/libslic3r/PrintConfig.cpp

@@ -3014,6 +3014,25 @@ void PrintConfigDef::init_fff_params()
     def->mode = comSimple;
     def->set_default_value(new ConfigOptionBool(false));
 
+    def = this->add("spiral_mode_smooth", coBool);
+    def->label = L("Smooth Spiral");
+    def->tooltip = L("Smooth Spiral smoothes out X and Y moves as well"
+                     "resulting in no visible seam at all, even in the XY directions on walls that are not vertical");
+    def->mode = comSimple;
+    def->set_default_value(new ConfigOptionBool(false));
+
+    def = this->add("spiral_mode_max_xy_smoothing", coFloatOrPercent);
+    def->label = L("Max XY Smoothing");
+    def->tooltip = L("Maximum distance to move points in XY to try to achieve a smooth spiral"
+                     "If expressed as a %, it will be computed over nozzle diameter");
+    def->sidetext = L("mm or %");
+    def->ratio_over = "nozzle_diameter";
+    def->min = 0;
+    def->max = 1000;
+    def->max_literal = 10;
+    def->mode = comAdvanced;
+    def->set_default_value(new ConfigOptionFloatOrPercent(200, true));
+
     def = this->add("timelapse_type", coEnum);
     def->label = L("Timelapse");
     def->tooltip = L("If smooth or traditional mode is selected, a timelapse video will be generated for each print. "

src/libslic3r/PrintConfig.hpp

@@ -1043,6 +1043,8 @@ PRINT_CONFIG_CLASS_DERIVED_DEFINE(
     ((ConfigOptionInt,                skirt_loops))
     ((ConfigOptionInts,               slow_down_layer_time))
     ((ConfigOptionBool,               spiral_mode))
+    ((ConfigOptionBool,               spiral_mode_smooth))
+    ((ConfigOptionFloatOrPercent,     spiral_mode_max_xy_smoothing))
     ((ConfigOptionInt,                standby_temperature_delta))
     ((ConfigOptionInts,               nozzle_temperature))
     ((ConfigOptionInts,               chamber_temperatures))

src/slic3r/GUI/ConfigManipulation.cpp

@@ -602,6 +602,8 @@ void ConfigManipulation::toggle_print_fff_options(DynamicPrintConfig *config, co
     toggle_line("sparse_infill_anchor", has_infill_anchors);
 
     bool has_spiral_vase         = config->opt_bool("spiral_mode");
+    toggle_line("spiral_mode_smooth", has_spiral_vase);
+    toggle_line("spiral_mode_max_xy_smoothing", config->opt_bool("spiral_mode_smooth"));
     bool has_top_solid_infill 	 = config->opt_int("top_shell_layers") > 0;
     bool has_bottom_solid_infill = config->opt_int("bottom_shell_layers") > 0;
     bool has_solid_infill 		 = has_top_solid_infill || has_bottom_solid_infill;

src/slic3r/GUI/Tab.cpp

@@ -2149,6 +2149,8 @@ void TabPrint::build()
         optgroup->append_single_option_line("slicing_mode");
         optgroup->append_single_option_line("print_sequence", "sequent-print");
         optgroup->append_single_option_line("spiral_mode", "spiral-vase");
+        optgroup->append_single_option_line("spiral_mode_smooth", "spiral-vase#smooth");
+        optgroup->append_single_option_line("spiral_mode_max_xy_smoothing", "spiral-vase#max-xy-smoothing");
         optgroup->append_single_option_line("timelapse_type", "Timelapse");
 
         optgroup->append_single_option_line("fuzzy_skin", "parameter/fuzzy-skin");