Replace QuickHull with Bullet's convex hull computer.

The code is based on the current version of thirdparty/vhacd and modified to use Godot's types and code style.

Additional changes:
- backported and extended PagedAllocator to allow leaked objects
- applied patch from https://github.com/bulletphysics/bullet3/pull/3037

COPYRIGHT.txt

@@ -55,6 +55,14 @@ Comment: Godot Engine logo
 Copyright: 2017, Andrea Calabró
 License: CC-BY-4.0
 
+Files: ./core/math/convex_hull.cpp
+ ./core/math/convex_hull.h
+Comment: Bullet Continuous Collision Detection and Physics Library
+Copyright: 2011, Ole Kniemeyer, MAXON, www.maxon.net
+ 2007-2021, Juan Linietsky, Ariel Manzur.
+ 2014-2021, Godot Engine contributors.
+License: Expat and Zlib
+
 Files: ./modules/fbx/fbx_parser/
 Comment: Open Asset Import Library (FBX parser)
 Copyright: 2006-2020, assimp team

core/math/convex_hull.h

@@ -0,0 +1,116 @@
+/*************************************************************************/
+/*  convex_hull.h                                                        */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+/*
+Copyright (c) 2011 Ole Kniemeyer, MAXON, www.maxon.net
+
+This software is provided 'as-is', without any express or implied warranty.
+In no event will the authors be held liable for any damages arising from the use of this software.
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it freely,
+subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+*/
+
+#ifndef CONVEX_HULL_H
+#define CONVEX_HULL_H
+
+#include "core/local_vector.h"
+#include "core/math/geometry.h"
+#include "core/math/vector3.h"
+#include "core/vector.h"
+
+/// Convex hull implementation based on Preparata and Hong
+/// See http://code.google.com/p/bullet/issues/detail?id=275
+/// Ole Kniemeyer, MAXON Computer GmbH
+class ConvexHullComputer {
+public:
+	class Edge {
+	private:
+		int32_t next = 0;
+		int32_t reverse = 0;
+		int32_t target_vertex = 0;
+
+		friend class ConvexHullComputer;
+
+	public:
+		int32_t get_source_vertex() const {
+			return (this + reverse)->target_vertex;
+		}
+
+		int32_t get_target_vertex() const {
+			return target_vertex;
+		}
+
+		const Edge *get_next_edge_of_vertex() const // clockwise list of all edges of a vertex
+		{
+			return this + next;
+		}
+
+		const Edge *get_next_edge_of_face() const // counter-clockwise list of all edges of a face
+		{
+			return (this + reverse)->get_next_edge_of_vertex();
+		}
+
+		const Edge *get_reverse_edge() const {
+			return this + reverse;
+		}
+	};
+
+	// Vertices of the output hull
+	Vector<Vector3> vertices;
+
+	// Edges of the output hull
+	LocalVector<Edge> edges;
+
+	// Faces of the convex hull. Each entry is an index into the "edges" array pointing to an edge of the face. Faces are planar n-gons
+	LocalVector<int32_t> faces;
+
+	/*
+		Compute convex hull of "count" vertices stored in "coords".
+		If "shrink" is positive, the convex hull is shrunken by that amount (each face is moved by "shrink" length units
+		towards the center along its normal).
+		If "shrinkClamp" is positive, "shrink" is clamped to not exceed "shrinkClamp * innerRadius", where "innerRadius"
+		is the minimum distance of a face to the center of the convex hull.
+
+		The returned value is the amount by which the hull has been shrunken. If it is negative, the amount was so large
+		that the resulting convex hull is empty.
+
+		The output convex hull can be found in the member variables "vertices", "edges", "faces".
+		*/
+	real_t compute(const Vector3 *p_coords, int32_t p_count, real_t p_shrink, real_t p_shrink_clamp);
+
+	static Error convex_hull(const Vector<Vector3> &p_points, Geometry::MeshData &r_mesh);
+};
+
+#endif // CONVEX_HULL_H

core/os/spin_lock.h

@@ -0,0 +1,51 @@
+/*************************************************************************/
+/*  spin_lock.h                                                          */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef SPIN_LOCK_H
+#define SPIN_LOCK_H
+
+#include "core/typedefs.h"
+
+#include <atomic>
+
+class SpinLock {
+	std::atomic_flag locked = ATOMIC_FLAG_INIT;
+
+public:
+	_ALWAYS_INLINE_ void lock() {
+		while (locked.test_and_set(std::memory_order_acquire)) {
+			;
+		}
+	}
+	_ALWAYS_INLINE_ void unlock() {
+		locked.clear(std::memory_order_release);
+	}
+};
+#endif // SPIN_LOCK_H

core/paged_allocator.h

@@ -0,0 +1,133 @@
+/*************************************************************************/
+/*  paged_allocator.h                                                    */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#ifndef PAGED_ALLOCATOR_H
+#define PAGED_ALLOCATOR_H
+
+#include "core/os/memory.h"
+#include "core/os/spin_lock.h"
+#include "core/typedefs.h"
+
+#include <type_traits>
+
+template <class T, bool thread_safe = false>
+class PagedAllocator {
+	T **page_pool = nullptr;
+	T ***available_pool = nullptr;
+	uint32_t pages_allocated = 0;
+	uint32_t allocs_available = 0;
+
+	uint32_t page_shift = 0;
+	uint32_t page_mask = 0;
+	uint32_t page_size = 0;
+	SpinLock spin_lock;
+
+public:
+	T *alloc() {
+		if (thread_safe) {
+			spin_lock.lock();
+		}
+		if (unlikely(allocs_available == 0)) {
+			uint32_t pages_used = pages_allocated;
+
+			pages_allocated++;
+			page_pool = (T **)memrealloc(page_pool, sizeof(T *) * pages_allocated);
+			available_pool = (T ***)memrealloc(available_pool, sizeof(T **) * pages_allocated);
+
+			page_pool[pages_used] = (T *)memalloc(sizeof(T) * page_size);
+			available_pool[pages_used] = (T **)memalloc(sizeof(T *) * page_size);
+
+			for (uint32_t i = 0; i < page_size; i++) {
+				available_pool[0][i] = &page_pool[pages_used][i];
+			}
+			allocs_available += page_size;
+		}
+
+		allocs_available--;
+		T *alloc = available_pool[allocs_available >> page_shift][allocs_available & page_mask];
+		if (thread_safe) {
+			spin_lock.unlock();
+		}
+		memnew_placement(alloc, T);
+		return alloc;
+	}
+
+	void free(T *p_mem) {
+		if (thread_safe) {
+			spin_lock.lock();
+		}
+		p_mem->~T();
+		available_pool[allocs_available >> page_shift][allocs_available & page_mask] = p_mem;
+		if (thread_safe) {
+			spin_lock.unlock();
+		}
+		allocs_available++;
+	}
+
+	void reset(bool p_allow_unfreed = false) {
+		if (!p_allow_unfreed || !std::is_trivially_destructible<T>::value) {
+			ERR_FAIL_COND(allocs_available < pages_allocated * page_size);
+		}
+		if (pages_allocated) {
+			for (uint32_t i = 0; i < pages_allocated; i++) {
+				memfree(page_pool[i]);
+				memfree(available_pool[i]);
+			}
+			memfree(page_pool);
+			memfree(available_pool);
+			page_pool = nullptr;
+			available_pool = nullptr;
+			pages_allocated = 0;
+			allocs_available = 0;
+		}
+	}
+	bool is_configured() const {
+		return page_size > 0;
+	}
+
+	void configure(uint32_t p_page_size) {
+		ERR_FAIL_COND(page_pool != nullptr); //sanity check
+		ERR_FAIL_COND(p_page_size == 0);
+		page_size = nearest_power_of_2_templated(p_page_size);
+		page_mask = page_size - 1;
+		page_shift = get_shift_from_power_of_2(page_size);
+	}
+
+	PagedAllocator(uint32_t p_page_size = 4096) { // power of 2 recommended because of alignment with OS page sizes. Even if element is bigger, its still a multiple and get rounded amount of pages
+		configure(p_page_size);
+	}
+
+	~PagedAllocator() {
+		ERR_FAIL_COND_MSG(allocs_available < pages_allocated * page_size, "Pages in use exist at exit in PagedAllocator");
+		reset();
+	}
+};
+
+#endif // PAGED_ALLOCATOR_H

editor/spatial_editor_gizmos.cpp

@@ -30,8 +30,8 @@
 
 #include "spatial_editor_gizmos.h"
 
+#include "core/math/convex_hull.h"
 #include "core/math/geometry.h"
-#include "core/math/quick_hull.h"
 #include "scene/3d/audio_stream_player_3d.h"
 #include "scene/3d/baked_lightmap.h"
 #include "scene/3d/collision_polygon.h"
@@ -3550,7 +3550,7 @@ void CollisionShapeSpatialGizmoPlugin::redraw(EditorSpatialGizmo *p_gizmo) {
 		if (points.size() > 3) {
 			Vector<Vector3> varr = Variant(points);
 			Geometry::MeshData md;
-			Error err = QuickHull::build(varr, md);
+			Error err = ConvexHullComputer::convex_hull(varr, md);
 			if (err == OK) {
 				Vector<Vector3> points2;
 				points2.resize(md.edges.size() * 2);

main/tests/test_physics.cpp

@@ -31,8 +31,8 @@
 #include "test_physics.h"
 
 #include "core/map.h"
+#include "core/math/convex_hull.h"
 #include "core/math/math_funcs.h"
-#include "core/math/quick_hull.h"
 #include "core/os/main_loop.h"
 #include "core/os/os.h"
 #include "core/print_string.h"
@@ -168,7 +168,7 @@ protected:
 
 		RID convex_mesh = vs->mesh_create();
 		Geometry::MeshData convex_data = Geometry::build_convex_mesh(convex_planes);
-		QuickHull::build(convex_data.vertices, convex_data);
+		ConvexHullComputer::convex_hull(convex_data.vertices, convex_data);
 		vs->mesh_add_surface_from_mesh_data(convex_mesh, convex_data);
 
 		type_mesh_map[PhysicsServer::SHAPE_CONVEX_POLYGON] = convex_mesh;

main/tests/test_render.cpp

@@ -30,8 +30,8 @@
 
 #include "test_render.h"
 
+#include "core/math/convex_hull.h"
 #include "core/math/math_funcs.h"
-#include "core/math/quick_hull.h"
 #include "core/os/keyboard.h"
 #include "core/os/main_loop.h"
 #include "core/os/os.h"
@@ -118,7 +118,7 @@ public:
 		vts.push_back(Vector3(-1, -1, -1));
 
 		Geometry::MeshData md;
-		Error err = QuickHull::build(vts, md);
+		Error err = ConvexHullComputer::convex_hull(vts, md);
 		print_line("ERR: " + itos(err));
 		test_cube = vs->mesh_create();
 		vs->mesh_add_surface_from_mesh_data(test_cube, md);

modules/recast/navigation_mesh_generator.cpp

@@ -29,7 +29,7 @@
 /*************************************************************************/
 
 #include "navigation_mesh_generator.h"
-#include "core/math/quick_hull.h"
+#include "core/math/convex_hull.h"
 #include "core/os/thread.h"
 #include "editor/editor_settings.h"
 #include "scene/3d/collision_shape.h"
@@ -213,7 +213,7 @@ void EditorNavigationMeshGenerator::_parse_geometry(Transform p_accumulated_tran
 						Vector<Vector3> varr = Variant(convex_polygon->get_points());
 						Geometry::MeshData md;
 
-						Error err = QuickHull::build(varr, md);
+						Error err = ConvexHullComputer::convex_hull(varr, md);
 
 						if (err == OK) {
 							PoolVector3Array faces;

scene/resources/convex_polygon_shape.cpp

@@ -29,7 +29,7 @@
 /*************************************************************************/
 
 #include "convex_polygon_shape.h"
-#include "core/math/quick_hull.h"
+#include "core/math/convex_hull.h"
 #include "servers/physics_server.h"
 
 Vector<Vector3> ConvexPolygonShape::get_debug_mesh_lines() {
@@ -38,7 +38,7 @@ Vector<Vector3> ConvexPolygonShape::get_debug_mesh_lines() {
 	if (points.size() > 3) {
 		Vector<Vector3> varr = Variant(points);
 		Geometry::MeshData md;
-		Error err = QuickHull::build(varr, md);
+		Error err = ConvexHullComputer::convex_hull(varr, md);
 		if (err == OK) {
 			Vector<Vector3> lines;
 			lines.resize(md.edges.size() * 2);

servers/physics/shape_sw.cpp

@@ -31,8 +31,8 @@
 #include "shape_sw.h"
 
 #include "core/image.h"
+#include "core/math/convex_hull.h"
 #include "core/math/geometry.h"
-#include "core/math/quick_hull.h"
 #include "core/sort_array.h"
 
 // HeightMapShapeSW is based on Bullet btHeightfieldTerrainShape.
@@ -1090,9 +1090,9 @@ Vector3 ConvexPolygonShapeSW::get_moment_of_inertia(real_t p_mass) const {
 }
 
 void ConvexPolygonShapeSW::_setup(const Vector<Vector3> &p_vertices) {
-	Error err = QuickHull::build(p_vertices, mesh);
+	Error err = ConvexHullComputer::convex_hull(p_vertices, mesh);
 	if (err != OK)
-		ERR_PRINT("Failed to build QuickHull");
+		ERR_PRINT("Failed to build convex hull");
 
 	AABB _aabb;