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

src/libslic3r/GCode.cpp

@@ -2729,12 +2729,13 @@ void GCode::process_layers(
         });
 
     const auto spiral_mode = tbb::make_filter<LayerResult, LayerResult>(slic3r_tbb_filtermode::serial_in_order,
-        [&spiral_mode = *this->m_spiral_vase.get()](LayerResult in) -> LayerResult {
+        [&spiral_mode = *this->m_spiral_vase.get(), &layers_to_print](LayerResult in) -> LayerResult {
         	if (in.nop_layer_result)
                 return in;
 
             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 pressure_equalizer = tbb::make_filter<LayerResult, LayerResult>(slic3r_tbb_filtermode::serial_in_order,
         [pressure_equalizer = this->m_pressure_equalizer.get()](LayerResult in) -> LayerResult {
@@ -2810,9 +2811,10 @@ void GCode::process_layers(
             }
         });
     const auto spiral_mode = tbb::make_filter<LayerResult, LayerResult>(slic3r_tbb_filtermode::serial_in_order,
-        [&spiral_mode = *this->m_spiral_vase.get()](LayerResult in)->LayerResult {
+        [&spiral_mode = *this->m_spiral_vase.get(), &layers_to_print](LayerResult in)->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<LayerResult, std::string>(slic3r_tbb_filtermode::serial_in_order,
         [&cooling_buffer = *this->m_cooling_buffer.get()](LayerResult in)->std::string {

src/libslic3r/GCode/SpiralVase.cpp

@@ -1,10 +1,70 @@
 #include "SpiralVase.hpp"
 #include "GCode.hpp"
 #include <sstream>
+#include <cmath>
+#include <limits>
 
 namespace Slic3r {
 
-std::string SpiralVase::process_layer(const std::string &gcode)
+/** == Smooth Spiral Helpers == */
+/** Distance between a and b */
+float distance(SpiralPoint a, SpiralPoint b) {
+    return sqrt(pow(a.x-b.x,2)+pow(a.y-b.y, 2));
+}
+
+SpiralPoint subtract(SpiralPoint a, SpiralPoint b) {
+    return SpiralPoint(a.x-b.x, a.y-b.y);
+}
+
+SpiralPoint add(SpiralPoint a, SpiralPoint b) {
+    return SpiralPoint(a.x+b.x, a.y+b.y);
+}
+
+SpiralPoint scale(SpiralPoint a, float factor){
+    return SpiralPoint(a.x*factor, a.y*factor);
+}
+
+/** dot product */
+float dot(SpiralPoint a, SpiralPoint b) {
+    return a.x*b.x+a.y*b.y;
+}
+
+/** Find the point on line ab closes to point c */
+SpiralPoint nearest_point_on_line(SpiralPoint c, SpiralPoint a, SpiralPoint b, float& dist) {
+    SpiralPoint ab = subtract(b, a);
+    SpiralPoint ca = subtract(c, a);
+    float t = dot(ca, ab)/dot(ab,ab);
+    t=t>1?1:t;
+    t=t<0?0:t;
+    SpiralPoint closest= 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 */
+SpiralPoint nearest_point_on_polygon(SpiralPoint p, std::vector<SpiralPoint>* points, bool& found, float& dist) {
+    if(points->size()<2) {
+        found=false;
+        return SpiralPoint(0,0);
+    }
+    float min     = std::numeric_limits<float>::max();
+    SpiralPoint closest(0,0);
+    for(unsigned long i=0; i<points->size()-1; i++) {
+        float currentDist=0;
+        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;
+
+}
+
+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 +105,27 @@ std::string SpiralVase::process_layer(const std::string &gcode)
             }
         });
     }
-    
+
     // Remove layer height from initial Z.
     z -= layer_height;
-
+
+    std::vector<SpiralPoint>* current_layer = new std::vector<SpiralPoint>();
+    std::vector<SpiralPoint>* previous_layer = m_previous_layer;
+
+    bool smooth_spiral = m_smooth_spiral;
     std::string new_gcode;
+    std::string transition_gcode;
+    // TODO: This should be proportional to line_width. Something like 2*line_width should be pretty good.
+    float max_xy_dist_for_smoothing = 0.8; // Made up threshold to prevent snapping to points too far away, Cura uses (2*line_width)^2
     //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]
+    SpiralPoint last_point = previous_layer != NULL && previous_layer->size() >0? previous_layer->at(previous_layer->size()-1): 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()) {
@@ -70,28 +138,69 @@ std::string SpiralVase::process_layer(const std::string &gcode)
                 float dist_XY = line.dist_XY(reader);
                 if (dist_XY > 0) {
                     // horizontal move
-                    if (line.extruding(reader)) {
+                    if (line.extruding(reader)) { // We need this to exclude retract and wipe moves!
                         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);
+                        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));
+                            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
+                            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;
+                                SpiralPoint nearestp = nearest_point_on_polygon(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
+                                    SpiralPoint target = add(scale(nearestp, 1 - factor), 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 = distance(last_point, target);
+                                    line.set(reader, E,
+                                             line.e() * modified_dist_XY / dist_XY); // Scale the extrusion amount according to change in length
+                                    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';
+        }
     });
+
+    delete m_previous_layer;
+    m_previous_layer = current_layer;
 
-    return new_gcode;
+    return new_gcode + transition_gcode;
 }
 
 }

src/libslic3r/GCode/SpiralVase.hpp

@@ -6,20 +6,32 @@
 
 namespace Slic3r {
 
+class SpiralPoint
+{
+    public:
+        SpiralPoint(float paramx, float paramy) : x(paramx), y(paramy) {}
+    public:
+        float x, y;
+
+};
+
 class SpiralVase {
+
 public:
     SpiralVase(const PrintConfig &config) : m_config(config)
     {
         m_reader.z() = (float)m_config.z_offset;
         m_reader.apply_config(m_config);
+        m_previous_layer = NULL;
+        m_smooth_spiral = config.spiral_mode_smooth;
     };
 
     void 		enable(bool en) {
    		m_transition_layer = en && ! m_enabled;
     	m_enabled 		   = en;
     }
 
-    std::string process_layer(const std::string &gcode);
+    std::string process_layer(const std::string &gcode, bool last_layer);
 
 private:
     const PrintConfig  &m_config;
@@ -28,8 +40,13 @@ class SpiralVase {
     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::vector<SpiralPoint> * m_previous_layer;
 };
 
+
+
 }
 
 #endif // slic3r_SpiralVase_hpp_

src/libslic3r/Preset.cpp

@@ -766,7 +766,7 @@ 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", "slicing_mode",
     "top_shell_layers", "top_shell_thickness", "bottom_shell_layers", "bottom_shell_thickness",
     "extra_perimeters_on_overhangs", "ensure_vertical_shell_thickness", "reduce_crossing_wall", "detect_thin_wall", "detect_overhang_wall", "overhang_reverse", "overhang_reverse_threshold","overhang_reverse_internal_only",
     "seam_position", "staggered_inner_seams", "wall_sequence", "is_infill_first", "sparse_infill_density", "sparse_infill_pattern", "top_surface_pattern", "bottom_surface_pattern",

src/libslic3r/PrintConfig.cpp

@@ -3427,6 +3427,13 @@ def = this->add("filament_loading_speed", coFloats);
     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("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

@@ -1120,6 +1120,7 @@ PRINT_CONFIG_CLASS_DERIVED_DEFINE(
     ((ConfigOptionFloat,              skirt_speed))
     ((ConfigOptionFloats,             slow_down_layer_time))
     ((ConfigOptionBool,               spiral_mode))
+    ((ConfigOptionBool,               spiral_mode_smooth))
     ((ConfigOptionInt,                standby_temperature_delta))
     ((ConfigOptionInts,               nozzle_temperature))
     ((ConfigOptionBools,              wipe))

src/slic3r/GUI/ConfigManipulation.cpp

@@ -505,6 +505,7 @@ void ConfigManipulation::toggle_print_fff_options(DynamicPrintConfig *config, co
     toggle_field("infill_anchor", has_infill_anchors);
 
     bool has_spiral_vase         = config->opt_bool("spiral_mode");
+    toggle_line("spiral_mode_smooth", has_spiral_vase);
     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

@@ -2159,6 +2159,7 @@ 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("timelapse_type", "Timelapse");
 
         optgroup->append_single_option_line("fuzzy_skin");