Initial port of organic tree support from PrusaSlicer (#1938)

* Initial port of organic tree support from PrusaSlicer

* Port missing Organic support parameters from PrusaSlicer

* Update parameter naming

* Reorganize the `raft_first_layer_expansion` and `raft_first_layer_density` parameters as they are not only used by rafts

* Reset support style only in simple mode

* Sync latest update from PrusaSlicer & copyrights

* Fix organic tree support crash with invalid parameters

---------

Co-authored-by: Vojtech Bubnik <bubnikv@gmail.com>

src/libslic3r/Support/SupportParameters.hpp

@@ -0,0 +1,100 @@
+///|/ Copyright (c) Prusa Research 2023 Vojtěch Bubník @bubnikv
+///|/
+///|/ PrusaSlicer is released under the terms of the AGPLv3 or higher
+///|/
+#ifndef slic3r_SupportParameters_hpp_
+#define slic3r_SupportParameters_hpp_
+
+#include "../libslic3r.h"
+#include "../Flow.hpp"
+
+namespace Slic3r {
+
+class PrintObject;
+enum InfillPattern : int;
+
+namespace FFFSupport {
+
+struct SupportParameters {
+	SupportParameters(const PrintObject &object);
+
+    // Both top / bottom contacts and interfaces are soluble.
+    bool                    soluble_interface;
+    // Support contact & interface are soluble, but support base is non-soluble.
+    bool                    soluble_interface_non_soluble_base;
+
+    // Is there at least a top contact layer extruded above support base?
+    bool                    has_top_contacts;
+    // Is there at least a bottom contact layer extruded below support base?
+    bool                    has_bottom_contacts;
+    // Number of top interface layers without counting the contact layer.
+    size_t                  num_top_interface_layers;
+    // Number of bottom interface layers without counting the contact layer.
+    size_t                  num_bottom_interface_layers;
+    // Number of top base interface layers. Zero if not soluble_interface_non_soluble_base.
+    size_t                  num_top_base_interface_layers;
+    // Number of bottom base interface layers. Zero if not soluble_interface_non_soluble_base.
+    size_t                  num_bottom_base_interface_layers;
+
+    bool                    has_contacts() const { return this->has_top_contacts || this->has_bottom_contacts; }
+    bool                    has_interfaces() const { return this->num_top_interface_layers + this->num_bottom_interface_layers > 0; }
+    bool                    has_base_interfaces() const { return this->num_top_base_interface_layers + this->num_bottom_base_interface_layers > 0; }
+    size_t                  num_top_interface_layers_only() const { return this->num_top_interface_layers - this->num_top_base_interface_layers; }
+    size_t                  num_bottom_interface_layers_only() const { return this->num_bottom_interface_layers - this->num_bottom_base_interface_layers; }
+
+	// Flow at the 1st print layer.
+	Flow 					first_layer_flow;
+	// Flow at the support base (neither top, nor bottom interface).
+	// Also flow at the raft base with the exception of raft interface and contact layers.
+	Flow 					support_material_flow;
+	// Flow at the top interface and contact layers.
+	Flow 					support_material_interface_flow;
+	// Flow at the bottom interfaces and contacts.
+	Flow 					support_material_bottom_interface_flow;
+	// Flow at raft inteface & contact layers.
+	Flow    				raft_interface_flow;
+	// Is merging of regions allowed? Could the interface & base support regions be printed with the same extruder?
+	bool 					can_merge_support_regions;
+
+    coordf_t 				support_layer_height_min;
+//	coordf_t				support_layer_height_max;
+
+	coordf_t				gap_xy;
+
+    float    				base_angle;
+    float    				interface_angle;
+
+    // Density of the top / bottom interface and contact layers.
+    coordf_t 				interface_density;
+    // Density of the raft interface and contact layers.
+    coordf_t 				raft_interface_density;
+    // Density of the base support layers.
+    coordf_t 				support_density;
+
+    // Pattern of the sparse infill including sparse raft layers.
+    InfillPattern           base_fill_pattern;
+    // Pattern of the top / bottom interface and contact layers.
+    InfillPattern           interface_fill_pattern;
+    // Pattern of the raft interface and contact layers.
+    InfillPattern           raft_interface_fill_pattern;
+    // Pattern of the contact layers.
+    InfillPattern 			contact_fill_pattern;
+    // Shall the sparse (base) layers be printed with a single perimeter line (sheath) for robustness?
+    bool                    with_sheath;
+    // Branches of organic supports with area larger than this threshold will be extruded with double lines.
+    double                  tree_branch_diameter_double_wall_area_scaled;
+
+    float 					raft_angle_1st_layer;
+    float 					raft_angle_base;
+    float 					raft_angle_interface;
+
+    // Produce a raft interface angle for a given SupportLayer::interface_id()
+    float 					raft_interface_angle(size_t interface_id) const 
+    	{ return this->raft_angle_interface + ((interface_id & 1) ? float(- M_PI / 4.) : float(+ M_PI / 4.)); }
+};
+
+} // namespace FFFSupport
+
+} // namespace Slic3r
+
+#endif /* slic3r_SupportParameters_hpp_ */