diff options
| -rw-r--r-- | servers/physics_3d/godot_collision_solver_3d_sat.cpp | 203 |
1 files changed, 102 insertions, 101 deletions
diff --git a/servers/physics_3d/godot_collision_solver_3d_sat.cpp b/servers/physics_3d/godot_collision_solver_3d_sat.cpp index 36c47a07b9..3f9567da51 100644 --- a/servers/physics_3d/godot_collision_solver_3d_sat.cpp +++ b/servers/physics_3d/godot_collision_solver_3d_sat.cpp @@ -758,24 +758,72 @@ public: typedef void (*CollisionFunc)(const GodotShape3D *, const Transform3D &, const GodotShape3D *, const Transform3D &, _CollectorCallback *p_callback, real_t, real_t); +// Perform analytic sphere-sphere collision and report results to collector template <bool withMargin> -static void _collision_sphere_sphere(const GodotShape3D *p_a, const Transform3D &p_transform_a, const GodotShape3D *p_b, const Transform3D &p_transform_b, _CollectorCallback *p_collector, real_t p_margin_a, real_t p_margin_b) { - const GodotSphereShape3D *sphere_A = static_cast<const GodotSphereShape3D *>(p_a); - const GodotSphereShape3D *sphere_B = static_cast<const GodotSphereShape3D *>(p_b); +static void analytic_sphere_collision(const Vector3 &p_origin_a, real_t p_radius_a, const Vector3 &p_origin_b, real_t p_radius_b, _CollectorCallback *p_collector, real_t p_margin_a, real_t p_margin_b) { + // Expand the spheres by the margins if enabled + if (withMargin) { + p_radius_a += p_margin_a; + p_radius_b += p_margin_b; + } - SeparatorAxisTest<GodotSphereShape3D, GodotSphereShape3D, withMargin> separator(sphere_A, p_transform_a, sphere_B, p_transform_b, p_collector, p_margin_a, p_margin_b); + // Get the vector from sphere B to A + Vector3 b_to_a = p_origin_a - p_origin_b; - // previous axis + // Get the length from B to A + real_t b_to_a_len = b_to_a.length(); - if (!separator.test_previous_axis()) { + // Calculate the sphere overlap, and bail if not overlapping + real_t overlap = p_radius_a + p_radius_b - b_to_a_len; + if (overlap < 0) return; - } - if (!separator.test_axis((p_transform_a.origin - p_transform_b.origin).normalized())) { + // Report collision + p_collector->collided = true; + + // Bail if there is no callback to receive the A and B collision points. + if (!p_collector->callback) { return; } - separator.generate_contacts(); + // Normalize the B to A vector + if (b_to_a_len < CMP_EPSILON) { + b_to_a = Vector3(0, 1, 0); // Spheres coincident, use arbitrary direction + } else { + b_to_a /= b_to_a_len; + } + + // Report collision points. The operations below are intended to minimize + // floating-point precision errors. This is done by calculating the first + // collision point from the smaller sphere, and then jumping across to + // the larger spheres collision point using the overlap distance. This + // jump is usually small even if the large sphere is massive, and so the + // second point will not suffer from precision errors. + if (p_radius_a < p_radius_b) { + Vector3 point_a = p_origin_a - b_to_a * p_radius_a; + Vector3 point_b = point_a + b_to_a * overlap; + p_collector->call(point_a, point_b); // Consider adding b_to_a vector + } else { + Vector3 point_b = p_origin_b + b_to_a * p_radius_b; + Vector3 point_a = point_b - b_to_a * overlap; + p_collector->call(point_a, point_b); // Consider adding b_to_a vector + } +} + +template <bool withMargin> +static void _collision_sphere_sphere(const GodotShape3D *p_a, const Transform3D &p_transform_a, const GodotShape3D *p_b, const Transform3D &p_transform_b, _CollectorCallback *p_collector, real_t p_margin_a, real_t p_margin_b) { + const GodotSphereShape3D *sphere_A = static_cast<const GodotSphereShape3D *>(p_a); + const GodotSphereShape3D *sphere_B = static_cast<const GodotSphereShape3D *>(p_b); + + // Perform an analytic sphere collision between the two spheres + analytic_sphere_collision<withMargin>( + p_transform_a.origin, + sphere_A->get_radius(), + p_transform_b.origin, + sphere_B->get_radius(), + p_collector, + p_margin_a, + p_margin_b); } template <bool withMargin> @@ -834,41 +882,26 @@ static void _collision_sphere_capsule(const GodotShape3D *p_a, const Transform3D const GodotSphereShape3D *sphere_A = static_cast<const GodotSphereShape3D *>(p_a); const GodotCapsuleShape3D *capsule_B = static_cast<const GodotCapsuleShape3D *>(p_b); - SeparatorAxisTest<GodotSphereShape3D, GodotCapsuleShape3D, withMargin> separator(sphere_A, p_transform_a, capsule_B, p_transform_b, p_collector, p_margin_a, p_margin_b); - - if (!separator.test_previous_axis()) { - return; - } - - //capsule sphere 1, sphere - - Vector3 capsule_axis = p_transform_b.basis.get_column(1) * (capsule_B->get_height() * 0.5 - capsule_B->get_radius()); - - Vector3 capsule_ball_1 = p_transform_b.origin + capsule_axis; - - if (!separator.test_axis((capsule_ball_1 - p_transform_a.origin).normalized())) { - return; - } - - //capsule sphere 2, sphere - - Vector3 capsule_ball_2 = p_transform_b.origin - capsule_axis; - - if (!separator.test_axis((capsule_ball_2 - p_transform_a.origin).normalized())) { - return; - } - - //capsule edge, sphere - - Vector3 b2a = p_transform_a.origin - p_transform_b.origin; - - Vector3 axis = b2a.cross(capsule_axis).cross(capsule_axis).normalized(); - - if (!separator.test_axis(axis)) { - return; - } - - separator.generate_contacts(); + real_t capsule_B_radius = capsule_B->get_radius(); + + // Construct the capsule segment (ball-center to ball-center) + Vector3 capsule_segment[2]; + Vector3 capsule_axis = p_transform_b.basis.get_column(1) * (capsule_B->get_height() * 0.5 - capsule_B_radius); + capsule_segment[0] = p_transform_b.origin + capsule_axis; + capsule_segment[1] = p_transform_b.origin - capsule_axis; + + // Get the capsules closest segment-point to the sphere + Vector3 capsule_closest = Geometry3D::get_closest_point_to_segment(p_transform_a.origin, capsule_segment); + + // Perform an analytic sphere collision between the sphere and the sphere-collider in the capsule + analytic_sphere_collision<withMargin>( + p_transform_a.origin, + sphere_A->get_radius(), + capsule_closest, + capsule_B_radius, + p_collector, + p_margin_a, + p_margin_b); } template <bool withMargin> @@ -1615,63 +1648,31 @@ static void _collision_capsule_capsule(const GodotShape3D *p_a, const Transform3 const GodotCapsuleShape3D *capsule_A = static_cast<const GodotCapsuleShape3D *>(p_a); const GodotCapsuleShape3D *capsule_B = static_cast<const GodotCapsuleShape3D *>(p_b); - SeparatorAxisTest<GodotCapsuleShape3D, GodotCapsuleShape3D, withMargin> separator(capsule_A, p_transform_a, capsule_B, p_transform_b, p_collector, p_margin_a, p_margin_b); - - if (!separator.test_previous_axis()) { - return; - } - - // some values - - Vector3 capsule_A_axis = p_transform_a.basis.get_column(1) * (capsule_A->get_height() * 0.5 - capsule_A->get_radius()); - Vector3 capsule_B_axis = p_transform_b.basis.get_column(1) * (capsule_B->get_height() * 0.5 - capsule_B->get_radius()); - - Vector3 capsule_A_ball_1 = p_transform_a.origin + capsule_A_axis; - Vector3 capsule_A_ball_2 = p_transform_a.origin - capsule_A_axis; - Vector3 capsule_B_ball_1 = p_transform_b.origin + capsule_B_axis; - Vector3 capsule_B_ball_2 = p_transform_b.origin - capsule_B_axis; - - //balls-balls - - if (!separator.test_axis((capsule_A_ball_1 - capsule_B_ball_1).normalized())) { - return; - } - if (!separator.test_axis((capsule_A_ball_1 - capsule_B_ball_2).normalized())) { - return; - } - - if (!separator.test_axis((capsule_A_ball_2 - capsule_B_ball_1).normalized())) { - return; - } - if (!separator.test_axis((capsule_A_ball_2 - capsule_B_ball_2).normalized())) { - return; - } - - // edges-balls - - if (!separator.test_axis((capsule_A_ball_1 - capsule_B_ball_1).cross(capsule_A_axis).cross(capsule_A_axis).normalized())) { - return; - } - - if (!separator.test_axis((capsule_A_ball_1 - capsule_B_ball_2).cross(capsule_A_axis).cross(capsule_A_axis).normalized())) { - return; - } - - if (!separator.test_axis((capsule_B_ball_1 - capsule_A_ball_1).cross(capsule_B_axis).cross(capsule_B_axis).normalized())) { - return; - } - - if (!separator.test_axis((capsule_B_ball_1 - capsule_A_ball_2).cross(capsule_B_axis).cross(capsule_B_axis).normalized())) { - return; - } - - // edges - - if (!separator.test_axis(capsule_A_axis.cross(capsule_B_axis).normalized())) { - return; - } - - separator.generate_contacts(); + real_t capsule_A_radius = capsule_A->get_radius(); + real_t capsule_B_radius = capsule_B->get_radius(); + + // Get the closest points between the capsule segments + Vector3 capsule_A_closest; + Vector3 capsule_B_closest; + Vector3 capsule_A_axis = p_transform_a.basis.get_column(1) * (capsule_A->get_height() * 0.5 - capsule_A_radius); + Vector3 capsule_B_axis = p_transform_b.basis.get_column(1) * (capsule_B->get_height() * 0.5 - capsule_B_radius); + Geometry3D::get_closest_points_between_segments( + p_transform_a.origin + capsule_A_axis, + p_transform_a.origin - capsule_A_axis, + p_transform_b.origin + capsule_B_axis, + p_transform_b.origin - capsule_B_axis, + capsule_A_closest, + capsule_B_closest); + + // Perform the analytic collision between the two closest capsule spheres + analytic_sphere_collision<withMargin>( + capsule_A_closest, + capsule_A_radius, + capsule_B_closest, + capsule_B_radius, + p_collector, + p_margin_a, + p_margin_b); } template <bool withMargin> |