Wipe tower postprocessing, wipe tower block on 3D plate improved.

- it renders red with one egde as indeterminate, the front edge is where the wipe tower will start
- changing width changes depth of the block (as requested)
- the block shows the brim of the wipe tower
- after slicing, the block is rendered in usual dark green and takes the exact shape of the tower (also with brim)
- moving or rotationg the block after slicing does not invalidate the wipe tower (and hence the exact block dimensions are preserved)
- changing anything that invalidates the wipe tower reverts the block back to the "indeterminate" shape
- the block is not shown after slicing, if the wipe tower is not actually generated (printing single color object with the wipe tower enabled)

This required changes in the wipe tower generator, which now generates the tower
at origin with no rotation. Resulting gcode is postprocessed and transformed during
gcode export. This means the wipe tower needs not be invalidated when it is moved or rotated.

4 files changed, 67 insertions, 41 deletions

diff --git a/xs/src/libslic3r/GCode/PrintExtents.cpp b/xs/src/libslic3r/GCode/PrintExtents.cpp
index 3c3f0f8d5..37b79f343 100644
--- a/xs/src/libslic3r/GCode/PrintExtents.cpp
+++ b/xs/src/libslic3r/GCode/PrintExtents.cpp
@@ -134,6 +134,11 @@ BoundingBoxf get_print_object_extrusions_extents(const PrintObject &print_object
 // The projection does not contain the priming regions.
 BoundingBoxf get_wipe_tower_extrusions_extents(const Print &print, const coordf_t max_print_z)
 {
+    // Wipe tower extrusions are saved as if the tower was at the origin with no rotation
+    // We need to get position and angle of the wipe tower to transform them to actual position.
+    Pointf wipe_tower_pos(print.config.wipe_tower_x.value, print.config.wipe_tower_y.value);
+    float wipe_tower_angle = print.config.wipe_tower_rotation_angle.value;
+
     BoundingBoxf bbox;
     for (const std::vector<WipeTower::ToolChangeResult> &tool_changes : print.m_wipe_tower_tool_changes) {
         if (! tool_changes.empty() && tool_changes.front().print_z > max_print_z)
@@ -144,6 +149,11 @@ BoundingBoxf get_wipe_tower_extrusions_extents(const Print &print, const coordf_
                 if (e.width > 0) {
                     Pointf  p1((&e - 1)->pos.x, (&e - 1)->pos.y);
                     Pointf  p2(e.pos.x, e.pos.y);
+                    p1.rotate(wipe_tower_angle);
+                    p1.translate(wipe_tower_pos);
+                    p2.rotate(wipe_tower_angle);
+                    p2.translate(wipe_tower_pos);
+
                     bbox.merge(p1);
                     coordf_t radius = 0.5 * e.width;
                     bbox.min.x = std::min(bbox.min.x, std::min(p1.x, p2.x) - radius);
diff --git a/xs/src/libslic3r/GCode/WipeTower.hpp b/xs/src/libslic3r/GCode/WipeTower.hpp
index 36cebeb84..9bf350328 100644
--- a/xs/src/libslic3r/GCode/WipeTower.hpp
+++ b/xs/src/libslic3r/GCode/WipeTower.hpp
@@ -25,18 +25,30 @@ public:
 		bool operator==(const xy &rhs) const { return x == rhs.x && y == rhs.y; }
 		bool operator!=(const xy &rhs) const { return x != rhs.x || y != rhs.y; }
 		
-		// Rotate the point around given point about given angle (in degrees)
-		// shifts the result so that point of rotation is in the middle of the tower
-		xy rotate(const xy& origin, float width, float depth, float angle) const {
+		// Rotate the point around center of the wipe tower about given angle (in degrees)
+		xy rotate(float width, float depth, float angle) const {
 			xy out(0,0);
 			float temp_x = x - width / 2.f;
 			float temp_y = y - depth / 2.f;
 			angle *= M_PI/180.;
-			out.x += (temp_x - origin.x) * cos(angle)  -  (temp_y - origin.y) * sin(angle);
-			out.y += (temp_x - origin.x) * sin(angle)  +  (temp_y - origin.y) * cos(angle);
-			return out + origin;
+			out.x += temp_x * cos(angle)  -  temp_y * sin(angle) + width / 2.f;
+			out.y += temp_x * sin(angle)  +  temp_y * cos(angle) + depth / 2.f;
+
+			return out;
 		}
-		
+        
+        // Rotate the point around origin about given angle in degrees
+        void rotate(float angle) {
+            float temp_x = x * cos(angle)  -  y * sin(angle);
+			y = x * sin(angle)  +  y * cos(angle);
+            x = temp_x;
+		}
+
+        void translate(const xy& vect) {
+            x += vect.x;
+            y += vect.y;
+        }
+
 		float x;
 		float y;
 	};
@@ -104,6 +116,9 @@ public:
 		// This is useful not only for the print time estimation, but also for the control of layer cooling.
 		float  				    elapsed_time;
 
+        // Is this a priming extrusion? (If so, the wipe tower rotation & translation will not be applied later)
+        bool                    priming;
+
 		// Sum the total length of the extrusion.
 		float total_extrusion_length_in_plane() {
 			float e_length = 0.f;
diff --git a/xs/src/libslic3r/GCode/WipeTowerPrusaMM.cpp b/xs/src/libslic3r/GCode/WipeTowerPrusaMM.cpp
index f466fc4f6..3d0dba07a 100644
--- a/xs/src/libslic3r/GCode/WipeTowerPrusaMM.cpp
+++ b/xs/src/libslic3r/GCode/WipeTowerPrusaMM.cpp
@@ -5,7 +5,7 @@ TODO LIST
 
 1. cooling moves - DONE
 2. account for perimeter and finish_layer extrusions and subtract it from last wipe - DONE
-3. priming extrusions (last wipe must clear the color)
+3. priming extrusions (last wipe must clear the color) - DONE
 4. Peter's wipe tower - layer's are not exactly square
 5. Peter's wipe tower - variable width for higher levels
 6. Peter's wipe tower - make sure it is not too sparse (apply max_bridge_distance and make last wipe longer)
@@ -17,7 +17,6 @@ TODO LIST
 
 #include <assert.h>
 #include <math.h>
-#include <fstream>
 #include <iostream>
 #include <vector>
 #include <numeric>
@@ -68,8 +67,11 @@ public:
             return *this;
     }
 
-	Writer& 			 set_initial_position(const WipeTower::xy &pos) { 
-		m_start_pos = WipeTower::xy(pos,0.f,m_y_shift).rotate(m_wipe_tower_pos, m_wipe_tower_width, m_wipe_tower_depth, m_angle_deg);
+	Writer& 			 set_initial_position(const WipeTower::xy &pos, float width = 0.f, float depth = 0.f, float internal_angle = 0.f) {
+        m_wipe_tower_width = width;
+        m_wipe_tower_depth = depth;
+        m_internal_angle = internal_angle;
+		m_start_pos = WipeTower::xy(pos,0.f,m_y_shift).rotate(m_wipe_tower_width, m_wipe_tower_depth, m_internal_angle);
 		m_current_pos = pos;
 		return *this;
 	}
@@ -81,9 +83,6 @@ public:
 
 	Writer& 			 set_extrusion_flow(float flow)
 		{ m_extrusion_flow = flow; return *this; }
-		
-	Writer&				 set_rotation(WipeTower::xy& pos, float width, float depth, float angle)
-		{ m_wipe_tower_pos = pos; m_wipe_tower_width = width; m_wipe_tower_depth=depth; m_angle_deg = angle; return (*this); }
 
 	Writer&				 set_y_shift(float shift) {
         m_current_pos.y -= shift-m_y_shift;
@@ -110,7 +109,7 @@ public:
 	float                y()     const { return m_current_pos.y; }
 	const WipeTower::xy& pos()   const { return m_current_pos; }
 	const WipeTower::xy	 start_pos_rotated() const { return m_start_pos; }
-	const WipeTower::xy  pos_rotated() const { return WipeTower::xy(m_current_pos,0.f,m_y_shift).rotate(m_wipe_tower_pos, m_wipe_tower_width, m_wipe_tower_depth, m_angle_deg); }
+	const WipeTower::xy  pos_rotated() const { return WipeTower::xy(m_current_pos, 0.f, m_y_shift).rotate(m_wipe_tower_width, m_wipe_tower_depth, m_internal_angle); }
 	float 				 elapsed_time() const { return m_elapsed_time; }
 
 	// Extrude with an explicitely provided amount of extrusion.
@@ -125,9 +124,9 @@ public:
 		double len = sqrt(dx*dx+dy*dy);
 
 
-		// For rotated wipe tower, transform position to printer coordinates
-		WipeTower::xy rotated_current_pos(WipeTower::xy(m_current_pos,0.f,m_y_shift).rotate(m_wipe_tower_pos, m_wipe_tower_width, m_wipe_tower_depth, m_angle_deg)); // this is where we are
-		WipeTower::xy rot(WipeTower::xy(x,y+m_y_shift).rotate(m_wipe_tower_pos, m_wipe_tower_width, m_wipe_tower_depth, m_angle_deg));                               // this is where we want to go
+		// Now do the "internal rotation" with respect to the wipe tower center
+		WipeTower::xy rotated_current_pos(WipeTower::xy(m_current_pos,0.f,m_y_shift).rotate(m_wipe_tower_width, m_wipe_tower_depth, m_internal_angle)); // this is where we are
+		WipeTower::xy rot(WipeTower::xy(x,y+m_y_shift).rotate(m_wipe_tower_width, m_wipe_tower_depth, m_internal_angle));                               // this is where we want to go
 
 		if (! m_preview_suppressed && e > 0.f && len > 0.) {
 			// Width of a squished extrusion, corrected for the roundings of the squished extrusions.
@@ -147,6 +146,7 @@ public:
 		if (std::abs(rot.y - rotated_current_pos.y) > EPSILON)
 			m_gcode += set_format_Y(rot.y);
 
+
 		if (e != 0.f)
 			m_gcode += set_format_E(e);
 
@@ -397,9 +397,8 @@ private:
 	std::string   m_gcode;
 	std::vector<WipeTower::Extrusion> m_extrusions;
 	float         m_elapsed_time;
-	float   	  m_angle_deg = 0.f;
+	float   	  m_internal_angle = 0.f;
 	float		  m_y_shift = 0.f;
-	WipeTower::xy m_wipe_tower_pos;
 	float 		  m_wipe_tower_width = 0.f;
 	float		  m_wipe_tower_depth = 0.f;
 	float		  m_last_fan_speed = 0.f;
@@ -539,6 +538,7 @@ WipeTower::ToolChangeResult WipeTowerPrusaMM::prime(
 	m_print_brim = true;
 
 	ToolChangeResult result;
+    result.priming      = true;
 	result.print_z 	  	= this->m_z_pos;
 	result.layer_height = this->m_layer_height;
 	result.gcode   	  	= writer.gcode();
@@ -575,7 +575,7 @@ WipeTower::ToolChangeResult WipeTowerPrusaMM::tool_change(unsigned int tool, boo
 	}
 
 	box_coordinates cleaning_box(
-		m_wipe_tower_pos + xy(m_perimeter_width / 2.f, m_perimeter_width / 2.f),
+		xy(m_perimeter_width / 2.f, m_perimeter_width / 2.f),
 		m_wipe_tower_width - m_perimeter_width,
 		(tool != (unsigned int)(-1) ? /*m_layer_info->depth*/wipe_area+m_depth_traversed-0.5*m_perimeter_width
                                     : m_wipe_tower_depth-m_perimeter_width));
@@ -584,7 +584,6 @@ WipeTower::ToolChangeResult WipeTowerPrusaMM::tool_change(unsigned int tool, boo
 	writer.set_extrusion_flow(m_extrusion_flow)
 		.set_z(m_z_pos)
 		.set_initial_tool(m_current_tool)
-		.set_rotation(m_wipe_tower_pos, m_wipe_tower_width, m_wipe_tower_depth, m_wipe_tower_rotation_angle)
 		.set_y_shift(m_y_shift + (tool!=(unsigned int)(-1) && (m_current_shape == SHAPE_REVERSED && !m_peters_wipe_tower) ? m_layer_info->depth - m_layer_info->toolchanges_depth(): 0.f))
 		.append(";--------------------\n"
 				"; CP TOOLCHANGE START\n")
@@ -594,7 +593,7 @@ WipeTower::ToolChangeResult WipeTowerPrusaMM::tool_change(unsigned int tool, boo
 		.speed_override(100);
 
 	xy initial_position = cleaning_box.ld + WipeTower::xy(0.f,m_depth_traversed);
-    writer.set_initial_position(initial_position);
+    writer.set_initial_position(initial_position, m_wipe_tower_width, m_wipe_tower_depth, m_internal_rotation);
 
     // Increase the extruder driver current to allow fast ramming.
     writer.set_extruder_trimpot(750);
@@ -616,11 +615,11 @@ WipeTower::ToolChangeResult WipeTowerPrusaMM::tool_change(unsigned int tool, boo
     if (last_change_in_layer) {// draw perimeter line
         writer.set_y_shift(m_y_shift);
         if (m_peters_wipe_tower)
-            writer.rectangle(m_wipe_tower_pos,m_layer_info->depth + 3*m_perimeter_width,m_wipe_tower_depth);
+            writer.rectangle(WipeTower::xy(0.f, 0.f),m_layer_info->depth + 3*m_perimeter_width,m_wipe_tower_depth);
         else {
-            writer.rectangle(m_wipe_tower_pos,m_wipe_tower_width, m_layer_info->depth + m_perimeter_width);
+            writer.rectangle(WipeTower::xy(0.f, 0.f),m_wipe_tower_width, m_layer_info->depth + m_perimeter_width);
             if (layer_finished()) { // no finish_layer will be called, we must wipe the nozzle
-                writer.travel(m_wipe_tower_pos.x + (writer.x()> (m_wipe_tower_pos.x + m_wipe_tower_width) / 2.f ? 0.f : m_wipe_tower_width), writer.y());
+                writer.travel(writer.x()> m_wipe_tower_width / 2.f ? 0.f : m_wipe_tower_width, writer.y());
             }
         }
     }
@@ -634,6 +633,7 @@ WipeTower::ToolChangeResult WipeTowerPrusaMM::tool_change(unsigned int tool, boo
                   "\n\n");
 
 	ToolChangeResult result;
+    result.priming      = false;
 	result.print_z 	  	= this->m_z_pos;
 	result.layer_height = this->m_layer_height;
 	result.gcode   	  	= writer.gcode();
@@ -647,7 +647,7 @@ WipeTower::ToolChangeResult WipeTowerPrusaMM::tool_change(unsigned int tool, boo
 WipeTower::ToolChangeResult WipeTowerPrusaMM::toolchange_Brim(bool sideOnly, float y_offset)
 {
 	const box_coordinates wipeTower_box(
-		m_wipe_tower_pos,
+		WipeTower::xy(0.f, 0.f),
 		m_wipe_tower_width,
 		m_wipe_tower_depth);
 
@@ -655,12 +655,11 @@ WipeTower::ToolChangeResult WipeTowerPrusaMM::toolchange_Brim(bool sideOnly, flo
 	writer.set_extrusion_flow(m_extrusion_flow * 1.1f)
 		  .set_z(m_z_pos) // Let the writer know the current Z position as a base for Z-hop.
 		  .set_initial_tool(m_current_tool)
-  		  .set_rotation(m_wipe_tower_pos, m_wipe_tower_width, m_wipe_tower_depth, m_wipe_tower_rotation_angle)
 		  .append(";-------------------------------------\n"
 				  "; CP WIPE TOWER FIRST LAYER BRIM START\n");
 
 	xy initial_position = wipeTower_box.lu - xy(m_perimeter_width * 6.f, 0);
-	writer.set_initial_position(initial_position);
+	writer.set_initial_position(initial_position, m_wipe_tower_width, m_wipe_tower_depth, m_internal_rotation);
 
     writer.extrude_explicit(wipeTower_box.ld - xy(m_perimeter_width * 6.f, 0), // Prime the extruder left of the wipe tower.
         1.5f * m_extrusion_flow * (wipeTower_box.lu.y - wipeTower_box.ld.y), 2400);
@@ -685,6 +684,7 @@ WipeTower::ToolChangeResult WipeTowerPrusaMM::toolchange_Brim(bool sideOnly, flo
     m_print_brim = false;  // Mark the brim as extruded
 
 	ToolChangeResult result;
+    result.priming      = false;
 	result.print_z 	  	= this->m_z_pos;
 	result.layer_height = this->m_layer_height;
 	result.gcode   	  	= writer.gcode();
@@ -724,7 +724,7 @@ void WipeTowerPrusaMM::toolchange_Unload(
     if (m_layer_info > m_plan.begin() && m_layer_info < m_plan.end() && (m_layer_info-1!=m_plan.begin() || !m_adhesion )) {
 
         // this is y of the center of previous sparse infill border
-        float sparse_beginning_y = m_wipe_tower_pos.y;
+        float sparse_beginning_y = 0.f;
         if (m_current_shape == SHAPE_REVERSED)
             sparse_beginning_y += ((m_layer_info-1)->depth - (m_layer_info-1)->toolchanges_depth())
                                       - ((m_layer_info)->depth-(m_layer_info)->toolchanges_depth()) ;
@@ -742,7 +742,7 @@ void WipeTowerPrusaMM::toolchange_Unload(
         for (const auto& tch : m_layer_info->tool_changes) {  // let's find this toolchange
             if (tch.old_tool == m_current_tool) {
                 sum_of_depths += tch.ramming_depth;
-                float ramming_end_y = m_wipe_tower_pos.y + sum_of_depths;
+                float ramming_end_y = sum_of_depths;
                 ramming_end_y -= (y_step/m_extra_spacing-m_perimeter_width) / 2.f;   // center of final ramming line
 
                 // debugging:
@@ -950,7 +950,7 @@ void WipeTowerPrusaMM::toolchange_Wipe(
     if (m_layer_info != m_plan.end() && m_current_tool != m_layer_info->tool_changes.back().new_tool) {
         m_left_to_right = !m_left_to_right;
         writer.travel(writer.x(), writer.y() - dy)
-        .travel(m_wipe_tower_pos.x + (m_left_to_right ? m_wipe_tower_width : 0.f), writer.y());
+        .travel(m_left_to_right ? m_wipe_tower_width : 0.f, writer.y());
     }
 
 	writer.set_extrusion_flow(m_extrusion_flow); // Reset the extrusion flow.
@@ -969,7 +969,6 @@ WipeTower::ToolChangeResult WipeTowerPrusaMM::finish_layer()
 	writer.set_extrusion_flow(m_extrusion_flow)
 		.set_z(m_z_pos)
 		.set_initial_tool(m_current_tool)
-		.set_rotation(m_wipe_tower_pos, m_wipe_tower_width, m_wipe_tower_depth, m_wipe_tower_rotation_angle)
 		.set_y_shift(m_y_shift - (m_current_shape == SHAPE_REVERSED && !m_peters_wipe_tower ? m_layer_info->toolchanges_depth() : 0.f))
 		.append(";--------------------\n"
 				"; CP EMPTY GRID START\n")
@@ -978,14 +977,12 @@ WipeTower::ToolChangeResult WipeTowerPrusaMM::finish_layer()
 	// Slow down on the 1st layer.
 	float speed_factor = m_is_first_layer ? 0.5f : 1.f;
 	float current_depth = m_layer_info->depth - m_layer_info->toolchanges_depth();
-	box_coordinates fill_box(m_wipe_tower_pos + xy(m_perimeter_width, m_depth_traversed + m_perimeter_width),
+	box_coordinates fill_box(xy(m_perimeter_width, m_depth_traversed + m_perimeter_width),
 							 m_wipe_tower_width - 2 * m_perimeter_width, current_depth-m_perimeter_width);
 
-    if (m_left_to_right) // so there is never a diagonal travel
-        writer.set_initial_position(fill_box.ru);
-    else
-        writer.set_initial_position(fill_box.lu);
 
+    writer.set_initial_position((m_left_to_right ? fill_box.ru : fill_box.lu), // so there is never a diagonal travel
+                                 m_wipe_tower_width, m_wipe_tower_depth, m_internal_rotation);
 
 	box_coordinates box = fill_box;
     for (int i=0;i<2;++i) {
@@ -1044,6 +1041,7 @@ WipeTower::ToolChangeResult WipeTowerPrusaMM::finish_layer()
     m_depth_traversed = m_wipe_tower_depth-m_perimeter_width;
 
 	ToolChangeResult result;
+    result.priming      = false;
 	result.print_z 	  	= this->m_z_pos;
 	result.layer_height = this->m_layer_height;
 	result.gcode   	  	= writer.gcode();
@@ -1165,9 +1163,9 @@ void WipeTowerPrusaMM::generate(std::vector<std::vector<WipeTower::ToolChangeRes
 	{
 		set_layer(layer.z,layer.height,0,layer.z == m_plan.front().z,layer.z == m_plan.back().z);
 		if (m_peters_wipe_tower)
-			m_wipe_tower_rotation_angle += 90.f;
+			m_internal_rotation += 90.f;
 		else
-            m_wipe_tower_rotation_angle += 180.f;
+            m_internal_rotation += 180.f;
 
 		if (!m_peters_wipe_tower && m_layer_info->depth < m_wipe_tower_depth - m_perimeter_width)
 			m_y_shift = (m_wipe_tower_depth-m_layer_info->depth-m_perimeter_width)/2.f;
@@ -1188,7 +1186,7 @@ void WipeTowerPrusaMM::generate(std::vector<std::vector<WipeTower::ToolChangeRes
 					last_toolchange.gcode += buf;
 				}
                 last_toolchange.gcode += finish_layer_toolchange.gcode;
-                last_toolchange.extrusions.insert(last_toolchange.extrusions.end(),finish_layer_toolchange.extrusions.begin(),finish_layer_toolchange.extrusions.end());
+                last_toolchange.extrusions.insert(last_toolchange.extrusions.end(), finish_layer_toolchange.extrusions.begin(), finish_layer_toolchange.extrusions.end());
                 last_toolchange.end_pos = finish_layer_toolchange.end_pos;
             }
             else
diff --git a/xs/src/libslic3r/GCode/WipeTowerPrusaMM.hpp b/xs/src/libslic3r/GCode/WipeTowerPrusaMM.hpp
index 1ae4616d8..e1529bcf4 100644
--- a/xs/src/libslic3r/GCode/WipeTowerPrusaMM.hpp
+++ b/xs/src/libslic3r/GCode/WipeTowerPrusaMM.hpp
@@ -102,6 +102,8 @@ public:
 	// Iterates through prepared m_plan, generates ToolChangeResults and appends them to "result"
 	void generate(std::vector<std::vector<WipeTower::ToolChangeResult>> &result);
 
+    float get_depth() const { return m_wipe_tower_depth; }
+
 
 
 	// Switch to a next layer.
@@ -189,6 +191,7 @@ private:
 	float  m_wipe_tower_width; 			// Width of the wipe tower.
 	float  m_wipe_tower_depth 	= 0.f; 	// Depth of the wipe tower
 	float  m_wipe_tower_rotation_angle = 0.f; // Wipe tower rotation angle in degrees (with respect to x axis)
+    float  m_internal_rotation  = 0.f;
 	float  m_y_shift			= 0.f;  // y shift passed to writer
 	float  m_z_pos 				= 0.f;  // Current Z position.
 	float  m_layer_height 		= 0.f; 	// Current layer height.