Merge pull request #53980 from nekomatata/rename-godot-physics-classes

1 files changed, 264 insertions, 0 deletions

diff --git a/servers/physics_2d/godot_collision_solver_2d.cpp b/servers/physics_2d/godot_collision_solver_2d.cpp
new file mode 100644
index 0000000000..25371b9885
--- /dev/null
+++ b/servers/physics_2d/godot_collision_solver_2d.cpp
@@ -0,0 +1,264 @@
+/*************************************************************************/
+/*  godot_collision_solver_2d.cpp                                        */
+/*************************************************************************/
+/*                       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.                */
+/*************************************************************************/
+
+#include "godot_collision_solver_2d.h"
+#include "godot_collision_solver_2d_sat.h"
+
+#define collision_solver sat_2d_calculate_penetration
+//#define collision_solver gjk_epa_calculate_penetration
+
+bool GodotCollisionSolver2D::solve_static_world_boundary(const GodotShape2D *p_shape_A, const Transform2D &p_transform_A, const GodotShape2D *p_shape_B, const Transform2D &p_transform_B, CallbackResult p_result_callback, void *p_userdata, bool p_swap_result) {
+	const GodotWorldBoundaryShape2D *world_boundary = static_cast<const GodotWorldBoundaryShape2D *>(p_shape_A);
+	if (p_shape_B->get_type() == PhysicsServer2D::SHAPE_WORLD_BOUNDARY) {
+		return false;
+	}
+
+	Vector2 n = p_transform_A.basis_xform(world_boundary->get_normal()).normalized();
+	Vector2 p = p_transform_A.xform(world_boundary->get_normal() * world_boundary->get_d());
+	real_t d = n.dot(p);
+
+	Vector2 supports[2];
+	int support_count;
+
+	p_shape_B->get_supports(p_transform_B.affine_inverse().basis_xform(-n).normalized(), supports, support_count);
+
+	bool found = false;
+
+	for (int i = 0; i < support_count; i++) {
+		supports[i] = p_transform_B.xform(supports[i]);
+		real_t pd = n.dot(supports[i]);
+		if (pd >= d) {
+			continue;
+		}
+		found = true;
+
+		Vector2 support_A = supports[i] - n * (pd - d);
+
+		if (p_result_callback) {
+			if (p_swap_result) {
+				p_result_callback(supports[i], support_A, p_userdata);
+			} else {
+				p_result_callback(support_A, supports[i], p_userdata);
+			}
+		}
+	}
+
+	return found;
+}
+
+bool GodotCollisionSolver2D::solve_separation_ray(const GodotShape2D *p_shape_A, const Vector2 &p_motion_A, const Transform2D &p_transform_A, const GodotShape2D *p_shape_B, const Transform2D &p_transform_B, CallbackResult p_result_callback, void *p_userdata, bool p_swap_result, Vector2 *r_sep_axis, real_t p_margin) {
+	const GodotSeparationRayShape2D *ray = static_cast<const GodotSeparationRayShape2D *>(p_shape_A);
+	if (p_shape_B->get_type() == PhysicsServer2D::SHAPE_SEPARATION_RAY) {
+		return false;
+	}
+
+	Vector2 from = p_transform_A.get_origin();
+	Vector2 to = from + p_transform_A[1] * (ray->get_length() + p_margin);
+	if (p_motion_A != Vector2()) {
+		//not the best but should be enough
+		Vector2 normal = (to - from).normalized();
+		to += normal * MAX(0.0, normal.dot(p_motion_A));
+	}
+	Vector2 support_A = to;
+
+	Transform2D invb = p_transform_B.affine_inverse();
+	from = invb.xform(from);
+	to = invb.xform(to);
+
+	Vector2 p, n;
+	if (!p_shape_B->intersect_segment(from, to, p, n)) {
+		if (r_sep_axis) {
+			*r_sep_axis = p_transform_A[1].normalized();
+		}
+		return false;
+	}
+
+	// Discard contacts when the ray is fully contained inside the shape.
+	if (n == Vector2()) {
+		if (r_sep_axis) {
+			*r_sep_axis = p_transform_A[1].normalized();
+		}
+		return false;
+	}
+
+	// Discard contacts in the wrong direction.
+	if (n.dot(from - to) < CMP_EPSILON) {
+		if (r_sep_axis) {
+			*r_sep_axis = p_transform_A[1].normalized();
+		}
+		return false;
+	}
+
+	Vector2 support_B = p_transform_B.xform(p);
+	if (ray->get_slide_on_slope()) {
+		Vector2 global_n = invb.basis_xform_inv(n).normalized();
+		support_B = support_A + (support_B - support_A).length() * global_n;
+	}
+
+	if (p_result_callback) {
+		if (p_swap_result) {
+			p_result_callback(support_B, support_A, p_userdata);
+		} else {
+			p_result_callback(support_A, support_B, p_userdata);
+		}
+	}
+	return true;
+}
+
+struct _ConcaveCollisionInfo2D {
+	const Transform2D *transform_A = nullptr;
+	const GodotShape2D *shape_A = nullptr;
+	const Transform2D *transform_B = nullptr;
+	Vector2 motion_A;
+	Vector2 motion_B;
+	real_t margin_A = 0.0;
+	real_t margin_B = 0.0;
+	GodotCollisionSolver2D::CallbackResult result_callback;
+	void *userdata = nullptr;
+	bool swap_result = false;
+	bool collided = false;
+	int aabb_tests = 0;
+	int collisions = 0;
+	Vector2 *sep_axis = nullptr;
+};
+
+bool GodotCollisionSolver2D::concave_callback(void *p_userdata, GodotShape2D *p_convex) {
+	_ConcaveCollisionInfo2D &cinfo = *(_ConcaveCollisionInfo2D *)(p_userdata);
+	cinfo.aabb_tests++;
+
+	bool collided = collision_solver(cinfo.shape_A, *cinfo.transform_A, cinfo.motion_A, p_convex, *cinfo.transform_B, cinfo.motion_B, cinfo.result_callback, cinfo.userdata, cinfo.swap_result, cinfo.sep_axis, cinfo.margin_A, cinfo.margin_B);
+	if (!collided) {
+		return false;
+	}
+
+	cinfo.collided = true;
+	cinfo.collisions++;
+
+	// Stop at first collision if contacts are not needed.
+	return !cinfo.result_callback;
+}
+
+bool GodotCollisionSolver2D::solve_concave(const GodotShape2D *p_shape_A, const Transform2D &p_transform_A, const Vector2 &p_motion_A, const GodotShape2D *p_shape_B, const Transform2D &p_transform_B, const Vector2 &p_motion_B, CallbackResult p_result_callback, void *p_userdata, bool p_swap_result, Vector2 *r_sep_axis, real_t p_margin_A, real_t p_margin_B) {
+	const GodotConcaveShape2D *concave_B = static_cast<const GodotConcaveShape2D *>(p_shape_B);
+
+	_ConcaveCollisionInfo2D cinfo;
+	cinfo.transform_A = &p_transform_A;
+	cinfo.shape_A = p_shape_A;
+	cinfo.transform_B = &p_transform_B;
+	cinfo.motion_A = p_motion_A;
+	cinfo.result_callback = p_result_callback;
+	cinfo.userdata = p_userdata;
+	cinfo.swap_result = p_swap_result;
+	cinfo.collided = false;
+	cinfo.collisions = 0;
+	cinfo.sep_axis = r_sep_axis;
+	cinfo.margin_A = p_margin_A;
+	cinfo.margin_B = p_margin_B;
+
+	cinfo.aabb_tests = 0;
+
+	Transform2D rel_transform = p_transform_A;
+	rel_transform.elements[2] -= p_transform_B.get_origin();
+
+	//quickly compute a local Rect2
+
+	Rect2 local_aabb;
+	for (int i = 0; i < 2; i++) {
+		Vector2 axis(p_transform_B.elements[i]);
+		real_t axis_scale = 1.0 / axis.length();
+		axis *= axis_scale;
+
+		real_t smin, smax;
+		p_shape_A->project_rangev(axis, rel_transform, smin, smax);
+		smin *= axis_scale;
+		smax *= axis_scale;
+
+		local_aabb.position[i] = smin;
+		local_aabb.size[i] = smax - smin;
+	}
+
+	concave_B->cull(local_aabb, concave_callback, &cinfo);
+
+	return cinfo.collided;
+}
+
+bool GodotCollisionSolver2D::solve(const GodotShape2D *p_shape_A, const Transform2D &p_transform_A, const Vector2 &p_motion_A, const GodotShape2D *p_shape_B, const Transform2D &p_transform_B, const Vector2 &p_motion_B, CallbackResult p_result_callback, void *p_userdata, Vector2 *r_sep_axis, real_t p_margin_A, real_t p_margin_B) {
+	PhysicsServer2D::ShapeType type_A = p_shape_A->get_type();
+	PhysicsServer2D::ShapeType type_B = p_shape_B->get_type();
+	bool concave_A = p_shape_A->is_concave();
+	bool concave_B = p_shape_B->is_concave();
+	real_t margin_A = p_margin_A, margin_B = p_margin_B;
+
+	bool swap = false;
+
+	if (type_A > type_B) {
+		SWAP(type_A, type_B);
+		SWAP(concave_A, concave_B);
+		SWAP(margin_A, margin_B);
+		swap = true;
+	}
+
+	if (type_A == PhysicsServer2D::SHAPE_WORLD_BOUNDARY) {
+		if (type_B == PhysicsServer2D::SHAPE_WORLD_BOUNDARY) {
+			return false;
+		}
+
+		if (swap) {
+			return solve_static_world_boundary(p_shape_B, p_transform_B, p_shape_A, p_transform_A, p_result_callback, p_userdata, true);
+		} else {
+			return solve_static_world_boundary(p_shape_A, p_transform_A, p_shape_B, p_transform_B, p_result_callback, p_userdata, false);
+		}
+
+	} else if (type_A == PhysicsServer2D::SHAPE_SEPARATION_RAY) {
+		if (type_B == PhysicsServer2D::SHAPE_SEPARATION_RAY) {
+			return false; //no ray-ray
+		}
+
+		if (swap) {
+			return solve_separation_ray(p_shape_B, p_motion_B, p_transform_B, p_shape_A, p_transform_A, p_result_callback, p_userdata, true, r_sep_axis, p_margin_B);
+		} else {
+			return solve_separation_ray(p_shape_A, p_motion_A, p_transform_A, p_shape_B, p_transform_B, p_result_callback, p_userdata, false, r_sep_axis, p_margin_A);
+		}
+
+	} else if (concave_B) {
+		if (concave_A) {
+			return false;
+		}
+
+		if (!swap) {
+			return solve_concave(p_shape_A, p_transform_A, p_motion_A, p_shape_B, p_transform_B, p_motion_B, p_result_callback, p_userdata, false, r_sep_axis, margin_A, margin_B);
+		} else {
+			return solve_concave(p_shape_B, p_transform_B, p_motion_B, p_shape_A, p_transform_A, p_motion_A, p_result_callback, p_userdata, true, r_sep_axis, margin_A, margin_B);
+		}
+
+	} else {
+		return collision_solver(p_shape_A, p_transform_A, p_motion_A, p_shape_B, p_transform_B, p_motion_B, p_result_callback, p_userdata, false, r_sep_axis, margin_A, margin_B);
+	}
+}