godot/scene/2d/physics/physics_body_2d.cpp

173 lines
8.2 KiB
C++

/**************************************************************************/
/* physics_body_2d.cpp */
/**************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
/* */
/* 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 */
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/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/**************************************************************************/
#include "physics_body_2d.h"
void PhysicsBody2D::_bind_methods() {
ClassDB::bind_method(D_METHOD("move_and_collide", "motion", "test_only", "safe_margin", "recovery_as_collision"), &PhysicsBody2D::_move, DEFVAL(false), DEFVAL(0.08), DEFVAL(false));
ClassDB::bind_method(D_METHOD("test_move", "from", "motion", "collision", "safe_margin", "recovery_as_collision"), &PhysicsBody2D::test_move, DEFVAL(Variant()), DEFVAL(0.08), DEFVAL(false));
ClassDB::bind_method(D_METHOD("get_gravity"), &PhysicsBody2D::get_gravity);
ClassDB::bind_method(D_METHOD("get_collision_exceptions"), &PhysicsBody2D::get_collision_exceptions);
ClassDB::bind_method(D_METHOD("add_collision_exception_with", "body"), &PhysicsBody2D::add_collision_exception_with);
ClassDB::bind_method(D_METHOD("remove_collision_exception_with", "body"), &PhysicsBody2D::remove_collision_exception_with);
}
PhysicsBody2D::PhysicsBody2D(PhysicsServer2D::BodyMode p_mode) :
CollisionObject2D(PhysicsServer2D::get_singleton()->body_create(), false) {
set_body_mode(p_mode);
set_pickable(false);
}
Ref<KinematicCollision2D> PhysicsBody2D::_move(const Vector2 &p_motion, bool p_test_only, real_t p_margin, bool p_recovery_as_collision) {
PhysicsServer2D::MotionParameters parameters(get_global_transform(), p_motion, p_margin);
parameters.recovery_as_collision = p_recovery_as_collision;
PhysicsServer2D::MotionResult result;
if (move_and_collide(parameters, result, p_test_only)) {
// Create a new instance when the cached reference is invalid or still in use in script.
if (motion_cache.is_null() || motion_cache->get_reference_count() > 1) {
motion_cache.instantiate();
motion_cache->owner_id = get_instance_id();
}
motion_cache->result = result;
return motion_cache;
}
return Ref<KinematicCollision2D>();
}
bool PhysicsBody2D::move_and_collide(const PhysicsServer2D::MotionParameters &p_parameters, PhysicsServer2D::MotionResult &r_result, bool p_test_only, bool p_cancel_sliding) {
if (is_only_update_transform_changes_enabled()) {
ERR_PRINT("Move functions do not work together with 'sync to physics' option. See the documentation for details.");
}
bool colliding = PhysicsServer2D::get_singleton()->body_test_motion(get_rid(), p_parameters, &r_result);
// Restore direction of motion to be along original motion,
// in order to avoid sliding due to recovery,
// but only if collision depth is low enough to avoid tunneling.
if (p_cancel_sliding) {
real_t motion_length = p_parameters.motion.length();
real_t precision = 0.001;
if (colliding) {
// Can't just use margin as a threshold because collision depth is calculated on unsafe motion,
// so even in normal resting cases the depth can be a bit more than the margin.
precision += motion_length * (r_result.collision_unsafe_fraction - r_result.collision_safe_fraction);
if (r_result.collision_depth > p_parameters.margin + precision) {
p_cancel_sliding = false;
}
}
if (p_cancel_sliding) {
// When motion is null, recovery is the resulting motion.
Vector2 motion_normal;
if (motion_length > CMP_EPSILON) {
motion_normal = p_parameters.motion / motion_length;
}
// Check depth of recovery.
real_t projected_length = r_result.travel.dot(motion_normal);
Vector2 recovery = r_result.travel - motion_normal * projected_length;
real_t recovery_length = recovery.length();
// Fixes cases where canceling slide causes the motion to go too deep into the ground,
// because we're only taking rest information into account and not general recovery.
if (recovery_length < p_parameters.margin + precision) {
// Apply adjustment to motion.
r_result.travel = motion_normal * projected_length;
r_result.remainder = p_parameters.motion - r_result.travel;
}
}
}
if (!p_test_only) {
Transform2D gt = p_parameters.from;
gt.columns[2] += r_result.travel;
set_global_transform(gt);
}
return colliding;
}
bool PhysicsBody2D::test_move(const Transform2D &p_from, const Vector2 &p_motion, const Ref<KinematicCollision2D> &r_collision, real_t p_margin, bool p_recovery_as_collision) {
ERR_FAIL_COND_V(!is_inside_tree(), false);
PhysicsServer2D::MotionResult *r = nullptr;
PhysicsServer2D::MotionResult temp_result;
if (r_collision.is_valid()) {
// Needs const_cast because method bindings don't support non-const Ref.
r = const_cast<PhysicsServer2D::MotionResult *>(&r_collision->result);
} else {
r = &temp_result;
}
PhysicsServer2D::MotionParameters parameters(p_from, p_motion, p_margin);
parameters.recovery_as_collision = p_recovery_as_collision;
return PhysicsServer2D::get_singleton()->body_test_motion(get_rid(), parameters, r);
}
Vector2 PhysicsBody2D::get_gravity() const {
PhysicsDirectBodyState2D *state = PhysicsServer2D::get_singleton()->body_get_direct_state(get_rid());
ERR_FAIL_NULL_V(state, Vector2());
return state->get_total_gravity();
}
TypedArray<PhysicsBody2D> PhysicsBody2D::get_collision_exceptions() {
List<RID> exceptions;
PhysicsServer2D::get_singleton()->body_get_collision_exceptions(get_rid(), &exceptions);
Array ret;
for (const RID &body : exceptions) {
ObjectID instance_id = PhysicsServer2D::get_singleton()->body_get_object_instance_id(body);
Object *obj = ObjectDB::get_instance(instance_id);
PhysicsBody2D *physics_body = Object::cast_to<PhysicsBody2D>(obj);
ret.append(physics_body);
}
return ret;
}
void PhysicsBody2D::add_collision_exception_with(Node *p_node) {
ERR_FAIL_NULL(p_node);
PhysicsBody2D *physics_body = Object::cast_to<PhysicsBody2D>(p_node);
ERR_FAIL_NULL_MSG(physics_body, "Collision exception only works between two nodes that inherit from PhysicsBody2D.");
PhysicsServer2D::get_singleton()->body_add_collision_exception(get_rid(), physics_body->get_rid());
}
void PhysicsBody2D::remove_collision_exception_with(Node *p_node) {
ERR_FAIL_NULL(p_node);
PhysicsBody2D *physics_body = Object::cast_to<PhysicsBody2D>(p_node);
ERR_FAIL_NULL_MSG(physics_body, "Collision exception only works between two nodes that inherit from PhysicsBody2D.");
PhysicsServer2D::get_singleton()->body_remove_collision_exception(get_rid(), physics_body->get_rid());
}