godot/scene/2d/joints_2d.cpp

/**************************************************************************/
/*  joints_2d.cpp                                                         */
/**************************************************************************/
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/*                             GODOT ENGINE                               */
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/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
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#include "joints_2d.h"

#include "core/engine.h"
#include "physics_body_2d.h"
#include "scene/scene_string_names.h"
#include "servers/physics_2d_server.h"

void Joint2D::_disconnect_signals() {
	Node *node_a = get_node_or_null(a);
	PhysicsBody2D *body_a = Object::cast_to<PhysicsBody2D>(node_a);
	if (body_a) {
		body_a->disconnect(SceneStringNames::get_singleton()->tree_exiting, this, SceneStringNames::get_singleton()->_body_exit_tree);
	}

	Node *node_b = get_node_or_null(b);
	PhysicsBody2D *body_b = Object::cast_to<PhysicsBody2D>(node_b);
	if (body_b) {
		body_b->disconnect(SceneStringNames::get_singleton()->tree_exiting, this, SceneStringNames::get_singleton()->_body_exit_tree);
	}
}

void Joint2D::_body_exit_tree() {
	_disconnect_signals();
	_update_joint(true);
}

void Joint2D::_update_joint(bool p_only_free) {
	if (joint.is_valid()) {
		if (ba.is_valid() && bb.is_valid() && exclude_from_collision) {
			Physics2DServer::get_singleton()->joint_disable_collisions_between_bodies(joint, false);
		}

		Physics2DServer::get_singleton()->free(joint);
		joint = RID();
		ba = RID();
		bb = RID();
	}

	if (p_only_free || !is_inside_tree()) {
		warning = String();
		return;
	}

	Node *node_a = get_node_or_null(a);
	Node *node_b = get_node_or_null(b);

	PhysicsBody2D *body_a = Object::cast_to<PhysicsBody2D>(node_a);
	PhysicsBody2D *body_b = Object::cast_to<PhysicsBody2D>(node_b);

	if (node_a && !body_a && node_b && !body_b) {
		warning = TTR("Node A and Node B must be PhysicsBody2Ds");
		update_configuration_warning();
		return;
	}

	if (node_a && !body_a) {
		warning = TTR("Node A must be a PhysicsBody2D");
		update_configuration_warning();
		return;
	}

	if (node_b && !body_b) {
		warning = TTR("Node B must be a PhysicsBody2D");
		update_configuration_warning();
		return;
	}

	if (!body_a || !body_b) {
		warning = TTR("Joint is not connected to two PhysicsBody2Ds");
		update_configuration_warning();
		return;
	}

	if (body_a == body_b) {
		warning = TTR("Node A and Node B must be different PhysicsBody2Ds");
		update_configuration_warning();
		return;
	}

	warning = String();
	update_configuration_warning();

	if (body_a) {
		body_a->force_update_transform();
	}

	if (body_b) {
		body_b->force_update_transform();
	}

	joint = _configure_joint(body_a, body_b);

	ERR_FAIL_COND_MSG(!joint.is_valid(), "Failed to configure the joint.");

	Physics2DServer::get_singleton()->get_singleton()->joint_set_param(joint, Physics2DServer::JOINT_PARAM_BIAS, bias);

	ba = body_a->get_rid();
	bb = body_b->get_rid();

	body_a->connect(SceneStringNames::get_singleton()->tree_exiting, this, SceneStringNames::get_singleton()->_body_exit_tree);
	body_b->connect(SceneStringNames::get_singleton()->tree_exiting, this, SceneStringNames::get_singleton()->_body_exit_tree);

	Physics2DServer::get_singleton()->joint_disable_collisions_between_bodies(joint, exclude_from_collision);
}

void Joint2D::set_node_a(const NodePath &p_node_a) {
	if (a == p_node_a) {
		return;
	}

	if (joint.is_valid()) {
		_disconnect_signals();
	}

	a = p_node_a;
	_update_joint();
}

NodePath Joint2D::get_node_a() const {
	return a;
}

void Joint2D::set_node_b(const NodePath &p_node_b) {
	if (b == p_node_b) {
		return;
	}

	if (joint.is_valid()) {
		_disconnect_signals();
	}

	b = p_node_b;
	_update_joint();
}
NodePath Joint2D::get_node_b() const {
	return b;
}

void Joint2D::_notification(int p_what) {
	switch (p_what) {
		case NOTIFICATION_POST_ENTER_TREE: {
			if (joint.is_valid()) {
				_disconnect_signals();
			}
			_update_joint();
		} break;
		case NOTIFICATION_EXIT_TREE: {
			if (joint.is_valid()) {
				_disconnect_signals();
			}
			_update_joint(true);
		} break;
	}
}

void Joint2D::set_bias(real_t p_bias) {
	bias = p_bias;
	if (joint.is_valid()) {
		Physics2DServer::get_singleton()->get_singleton()->joint_set_param(joint, Physics2DServer::JOINT_PARAM_BIAS, bias);
	}
}

real_t Joint2D::get_bias() const {
	return bias;
}

void Joint2D::set_exclude_nodes_from_collision(bool p_enable) {
	if (exclude_from_collision == p_enable) {
		return;
	}
	if (joint.is_valid()) {
		_disconnect_signals();
	}
	_update_joint(true);
	exclude_from_collision = p_enable;
	_update_joint();
}

bool Joint2D::get_exclude_nodes_from_collision() const {
	return exclude_from_collision;
}

String Joint2D::get_configuration_warning() const {
	String node_warning = Node2D::get_configuration_warning();

	if (!warning.empty()) {
		if (!node_warning.empty()) {
			node_warning += "\n\n";
		}
		node_warning += warning;
	}

	return node_warning;
}

void Joint2D::_bind_methods() {
	ClassDB::bind_method(D_METHOD("_body_exit_tree"), &Joint2D::_body_exit_tree);

	ClassDB::bind_method(D_METHOD("set_node_a", "node"), &Joint2D::set_node_a);
	ClassDB::bind_method(D_METHOD("get_node_a"), &Joint2D::get_node_a);

	ClassDB::bind_method(D_METHOD("set_node_b", "node"), &Joint2D::set_node_b);
	ClassDB::bind_method(D_METHOD("get_node_b"), &Joint2D::get_node_b);

	ClassDB::bind_method(D_METHOD("set_bias", "bias"), &Joint2D::set_bias);
	ClassDB::bind_method(D_METHOD("get_bias"), &Joint2D::get_bias);

	ClassDB::bind_method(D_METHOD("set_exclude_nodes_from_collision", "enable"), &Joint2D::set_exclude_nodes_from_collision);
	ClassDB::bind_method(D_METHOD("get_exclude_nodes_from_collision"), &Joint2D::get_exclude_nodes_from_collision);

	ADD_PROPERTY(PropertyInfo(Variant::NODE_PATH, "node_a", PROPERTY_HINT_NODE_PATH_VALID_TYPES, "PhysicsBody2D"), "set_node_a", "get_node_a");
	ADD_PROPERTY(PropertyInfo(Variant::NODE_PATH, "node_b", PROPERTY_HINT_NODE_PATH_VALID_TYPES, "PhysicsBody2D"), "set_node_b", "get_node_b");
	ADD_PROPERTY(PropertyInfo(Variant::REAL, "bias", PROPERTY_HINT_RANGE, "0,0.9,0.001"), "set_bias", "get_bias");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "disable_collision"), "set_exclude_nodes_from_collision", "get_exclude_nodes_from_collision");
}

Joint2D::Joint2D() {
	bias = 0;
	exclude_from_collision = true;
}

///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////

void PinJoint2D::_notification(int p_what) {
	switch (p_what) {
		case NOTIFICATION_DRAW: {
			if (!is_inside_tree()) {
				break;
			}

			if (!Engine::get_singleton()->is_editor_hint() && !get_tree()->is_debugging_collisions_hint()) {
				break;
			}

			draw_line(Point2(-10, 0), Point2(+10, 0), Color(0.7, 0.6, 0.0, 0.5), 3);
			draw_line(Point2(0, -10), Point2(0, +10), Color(0.7, 0.6, 0.0, 0.5), 3);
		} break;
	}
}

RID PinJoint2D::_configure_joint(PhysicsBody2D *body_a, PhysicsBody2D *body_b) {
	RID pj = Physics2DServer::get_singleton()->pin_joint_create(get_global_transform().get_origin(), body_a->get_rid(), body_b ? body_b->get_rid() : RID());
	Physics2DServer::get_singleton()->pin_joint_set_param(pj, Physics2DServer::PIN_JOINT_SOFTNESS, softness);
	return pj;
}

void PinJoint2D::set_softness(real_t p_softness) {
	softness = p_softness;
	update();
	if (get_joint().is_valid()) {
		Physics2DServer::get_singleton()->pin_joint_set_param(get_joint(), Physics2DServer::PIN_JOINT_SOFTNESS, p_softness);
	}
}

real_t PinJoint2D::get_softness() const {
	return softness;
}

void PinJoint2D::_bind_methods() {
	ClassDB::bind_method(D_METHOD("set_softness", "softness"), &PinJoint2D::set_softness);
	ClassDB::bind_method(D_METHOD("get_softness"), &PinJoint2D::get_softness);

	ADD_PROPERTY(PropertyInfo(Variant::REAL, "softness", PROPERTY_HINT_EXP_RANGE, "0.00,16,0.01"), "set_softness", "get_softness");
}

PinJoint2D::PinJoint2D() {
	softness = 0;
}

///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////

void GrooveJoint2D::_notification(int p_what) {
	switch (p_what) {
		case NOTIFICATION_DRAW: {
			if (!is_inside_tree()) {
				break;
			}

			if (!Engine::get_singleton()->is_editor_hint() && !get_tree()->is_debugging_collisions_hint()) {
				break;
			}

			draw_line(Point2(-10, 0), Point2(+10, 0), Color(0.7, 0.6, 0.0, 0.5), 3);
			draw_line(Point2(-10, length), Point2(+10, length), Color(0.7, 0.6, 0.0, 0.5), 3);
			draw_line(Point2(0, 0), Point2(0, length), Color(0.7, 0.6, 0.0, 0.5), 3);
			draw_line(Point2(-10, initial_offset), Point2(+10, initial_offset), Color(0.8, 0.8, 0.9, 0.5), 5);
		} break;
	}
}

RID GrooveJoint2D::_configure_joint(PhysicsBody2D *body_a, PhysicsBody2D *body_b) {
	Transform2D gt = get_global_transform();
	Vector2 groove_A1 = gt.get_origin();
	Vector2 groove_A2 = gt.xform(Vector2(0, length));
	Vector2 anchor_B = gt.xform(Vector2(0, initial_offset));

	return Physics2DServer::get_singleton()->groove_joint_create(groove_A1, groove_A2, anchor_B, body_a->get_rid(), body_b->get_rid());
}

void GrooveJoint2D::set_length(real_t p_length) {
	length = p_length;
	update();
}

real_t GrooveJoint2D::get_length() const {
	return length;
}

void GrooveJoint2D::set_initial_offset(real_t p_initial_offset) {
	initial_offset = p_initial_offset;
	update();
}

real_t GrooveJoint2D::get_initial_offset() const {
	return initial_offset;
}

void GrooveJoint2D::_bind_methods() {
	ClassDB::bind_method(D_METHOD("set_length", "length"), &GrooveJoint2D::set_length);
	ClassDB::bind_method(D_METHOD("get_length"), &GrooveJoint2D::get_length);
	ClassDB::bind_method(D_METHOD("set_initial_offset", "offset"), &GrooveJoint2D::set_initial_offset);
	ClassDB::bind_method(D_METHOD("get_initial_offset"), &GrooveJoint2D::get_initial_offset);

	ADD_PROPERTY(PropertyInfo(Variant::REAL, "length", PROPERTY_HINT_EXP_RANGE, "1,65535,1"), "set_length", "get_length");
	ADD_PROPERTY(PropertyInfo(Variant::REAL, "initial_offset", PROPERTY_HINT_EXP_RANGE, "1,65535,1"), "set_initial_offset", "get_initial_offset");
}

GrooveJoint2D::GrooveJoint2D() {
	length = 50;
	initial_offset = 25;
}

///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////

void DampedSpringJoint2D::_notification(int p_what) {
	switch (p_what) {
		case NOTIFICATION_DRAW: {
			if (!is_inside_tree()) {
				break;
			}

			if (!Engine::get_singleton()->is_editor_hint() && !get_tree()->is_debugging_collisions_hint()) {
				break;
			}

			draw_line(Point2(-10, 0), Point2(+10, 0), Color(0.7, 0.6, 0.0, 0.5), 3);
			draw_line(Point2(-10, length), Point2(+10, length), Color(0.7, 0.6, 0.0, 0.5), 3);
			draw_line(Point2(0, 0), Point2(0, length), Color(0.7, 0.6, 0.0, 0.5), 3);
		} break;
	}
}

RID DampedSpringJoint2D::_configure_joint(PhysicsBody2D *body_a, PhysicsBody2D *body_b) {
	Transform2D gt = get_global_transform();
	Vector2 anchor_A = gt.get_origin();
	Vector2 anchor_B = gt.xform(Vector2(0, length));

	RID dsj = Physics2DServer::get_singleton()->damped_spring_joint_create(anchor_A, anchor_B, body_a->get_rid(), body_b->get_rid());
	if (rest_length) {
		Physics2DServer::get_singleton()->damped_string_joint_set_param(dsj, Physics2DServer::DAMPED_STRING_REST_LENGTH, rest_length);
	}
	Physics2DServer::get_singleton()->damped_string_joint_set_param(dsj, Physics2DServer::DAMPED_STRING_STIFFNESS, stiffness);
	Physics2DServer::get_singleton()->damped_string_joint_set_param(dsj, Physics2DServer::DAMPED_STRING_DAMPING, damping);

	return dsj;
}

void DampedSpringJoint2D::set_length(real_t p_length) {
	length = p_length;
	update();
}

real_t DampedSpringJoint2D::get_length() const {
	return length;
}

void DampedSpringJoint2D::set_rest_length(real_t p_rest_length) {
	rest_length = p_rest_length;
	update();
	if (get_joint().is_valid()) {
		Physics2DServer::get_singleton()->damped_string_joint_set_param(get_joint(), Physics2DServer::DAMPED_STRING_REST_LENGTH, p_rest_length ? p_rest_length : length);
	}
}

real_t DampedSpringJoint2D::get_rest_length() const {
	return rest_length;
}

void DampedSpringJoint2D::set_stiffness(real_t p_stiffness) {
	stiffness = p_stiffness;
	update();
	if (get_joint().is_valid()) {
		Physics2DServer::get_singleton()->damped_string_joint_set_param(get_joint(), Physics2DServer::DAMPED_STRING_STIFFNESS, p_stiffness);
	}
}

real_t DampedSpringJoint2D::get_stiffness() const {
	return stiffness;
}

void DampedSpringJoint2D::set_damping(real_t p_damping) {
	damping = p_damping;
	update();
	if (get_joint().is_valid()) {
		Physics2DServer::get_singleton()->damped_string_joint_set_param(get_joint(), Physics2DServer::DAMPED_STRING_DAMPING, p_damping);
	}
}

real_t DampedSpringJoint2D::get_damping() const {
	return damping;
}

void DampedSpringJoint2D::_bind_methods() {
	ClassDB::bind_method(D_METHOD("set_length", "length"), &DampedSpringJoint2D::set_length);
	ClassDB::bind_method(D_METHOD("get_length"), &DampedSpringJoint2D::get_length);
	ClassDB::bind_method(D_METHOD("set_rest_length", "rest_length"), &DampedSpringJoint2D::set_rest_length);
	ClassDB::bind_method(D_METHOD("get_rest_length"), &DampedSpringJoint2D::get_rest_length);
	ClassDB::bind_method(D_METHOD("set_stiffness", "stiffness"), &DampedSpringJoint2D::set_stiffness);
	ClassDB::bind_method(D_METHOD("get_stiffness"), &DampedSpringJoint2D::get_stiffness);
	ClassDB::bind_method(D_METHOD("set_damping", "damping"), &DampedSpringJoint2D::set_damping);
	ClassDB::bind_method(D_METHOD("get_damping"), &DampedSpringJoint2D::get_damping);

	ADD_PROPERTY(PropertyInfo(Variant::REAL, "length", PROPERTY_HINT_EXP_RANGE, "1,65535,1"), "set_length", "get_length");
	ADD_PROPERTY(PropertyInfo(Variant::REAL, "rest_length", PROPERTY_HINT_EXP_RANGE, "0,65535,1"), "set_rest_length", "get_rest_length");
	ADD_PROPERTY(PropertyInfo(Variant::REAL, "stiffness", PROPERTY_HINT_EXP_RANGE, "0.1,64,0.1"), "set_stiffness", "get_stiffness");
	ADD_PROPERTY(PropertyInfo(Variant::REAL, "damping", PROPERTY_HINT_EXP_RANGE, "0.01,16,0.01"), "set_damping", "get_damping");
}

DampedSpringJoint2D::DampedSpringJoint2D() {
	length = 50;
	rest_length = 0;
	stiffness = 20;
	damping = 1;
}