/*************************************************************************/ /* godot_collision_solver_2d.cpp */ /*************************************************************************/ /* This file is part of: */ /* GODOT ENGINE */ /* https://godotengine.org */ /*************************************************************************/ /* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur. */ /* Copyright (c) 2014-2022 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, const Vector2 &p_motion_B, CallbackResult p_result_callback, void *p_userdata, bool p_swap_result, real_t p_margin) { 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_margin * supports[i].normalized(); supports[i] = p_transform_B.xform(supports[i]); supports[i] += p_motion_B; 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 = nullptr; 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 = *(static_cast<_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.columns[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.columns[i]); real_t axis_scale = 1.0 / axis.length(); axis *= axis_scale; real_t smin = 0.0, smax = 0.0; 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) { WARN_PRINT_ONCE("Collisions between world boundaries are not supported."); return false; } if (swap) { return solve_static_world_boundary(p_shape_B, p_transform_B, p_shape_A, p_transform_A, p_motion_A, p_result_callback, p_userdata, true, p_margin_A); } else { return solve_static_world_boundary(p_shape_A, p_transform_A, p_shape_B, p_transform_B, p_motion_B, p_result_callback, p_userdata, false, p_margin_B); } } else if (type_A == PhysicsServer2D::SHAPE_SEPARATION_RAY) { if (type_B == PhysicsServer2D::SHAPE_SEPARATION_RAY) { WARN_PRINT_ONCE("Collisions between two rays are not supported."); 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) { WARN_PRINT_ONCE("Collisions between two concave shapes are not supported."); 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); } }