virtualx-engine/servers/physics_2d/body_2d_sw.cpp
Josh Grams f7d31cec38 RigidBody2D: add and bind get_inertia() method.
You can't set this value very well, since it's automatically computed
from the mass and the collision shapes. But since the values are higher
than many people might suspect, so being able to read it helps estimate
the amount of torque you might need to apply.
2016-04-20 20:49:37 -04:00

732 lines
18 KiB
C++

/*************************************************************************/
/* body_2d_sw.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* http://www.godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2016 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, */
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/* included in all copies or substantial portions of the Software. */
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/* 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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#include "body_2d_sw.h"
#include "space_2d_sw.h"
#include "area_2d_sw.h"
#include "physics_2d_server_sw.h"
void Body2DSW::_update_inertia() {
if (get_space() && !inertia_update_list.in_list())
get_space()->body_add_to_inertia_update_list(&inertia_update_list);
}
void Body2DSW::update_inertias() {
//update shapes and motions
switch(mode) {
case Physics2DServer::BODY_MODE_RIGID: {
//update tensor for allshapes, not the best way but should be somehow OK. (inspired from bullet)
float total_area=0;
for (int i=0;i<get_shape_count();i++) {
total_area+=get_shape_aabb(i).get_area();
}
real_t _inertia=0;
for (int i=0;i<get_shape_count();i++) {
const Shape2DSW* shape=get_shape(i);
float area=get_shape_aabb(i).get_area();
float mass = area * this->mass / total_area;
Matrix32 mtx = get_shape_transform(i);
Vector2 scale = mtx.get_scale();
_inertia += shape->get_moment_of_inertia(mass,scale) + mass * mtx.get_origin().length_squared();
//Rect2 ab = get_shape_aabb(i);
//_inertia+=mass*ab.size.dot(ab.size)/12.0f;
}
if (_inertia!=0)
_inv_inertia=1.0/_inertia;
else
_inv_inertia=0.0; //wathever
if (mass)
_inv_mass=1.0/mass;
else
_inv_mass=0;
} break;
case Physics2DServer::BODY_MODE_KINEMATIC:
case Physics2DServer::BODY_MODE_STATIC: {
_inv_inertia=0;
_inv_mass=0;
} break;
case Physics2DServer::BODY_MODE_CHARACTER: {
_inv_inertia=0;
_inv_mass=1.0/mass;
} break;
}
//_update_inertia_tensor();
//_update_shapes();
}
void Body2DSW::set_active(bool p_active) {
if (active==p_active)
return;
active=p_active;
if (!p_active) {
if (get_space())
get_space()->body_remove_from_active_list(&active_list);
} else {
if (mode==Physics2DServer::BODY_MODE_STATIC)
return; //static bodies can't become active
if (get_space())
get_space()->body_add_to_active_list(&active_list);
//still_time=0;
}
/*
if (!space)
return;
for(int i=0;i<get_shape_count();i++) {
Shape &s=shapes[i];
if (s.bpid>0) {
get_space()->get_broadphase()->set_active(s.bpid,active);
}
}
*/
}
void Body2DSW::set_param(Physics2DServer::BodyParameter p_param, float p_value) {
switch(p_param) {
case Physics2DServer::BODY_PARAM_BOUNCE: {
bounce=p_value;
} break;
case Physics2DServer::BODY_PARAM_FRICTION: {
friction=p_value;
} break;
case Physics2DServer::BODY_PARAM_MASS: {
ERR_FAIL_COND(p_value<=0);
mass=p_value;
_update_inertia();
} break;
case Physics2DServer::BODY_PARAM_GRAVITY_SCALE: {
gravity_scale=p_value;
} break;
case Physics2DServer::BODY_PARAM_LINEAR_DAMP: {
linear_damp=p_value;
} break;
case Physics2DServer::BODY_PARAM_ANGULAR_DAMP: {
angular_damp=p_value;
} break;
default:{}
}
}
float Body2DSW::get_param(Physics2DServer::BodyParameter p_param) const {
switch(p_param) {
case Physics2DServer::BODY_PARAM_BOUNCE: {
return bounce;
} break;
case Physics2DServer::BODY_PARAM_FRICTION: {
return friction;
} break;
case Physics2DServer::BODY_PARAM_MASS: {
return mass;
} break;
case Physics2DServer::BODY_PARAM_INERTIA: {
if(_inv_inertia == 0) return INFINITY;
else return 1.0 / _inv_inertia;
} break;
case Physics2DServer::BODY_PARAM_GRAVITY_SCALE: {
return gravity_scale;
} break;
case Physics2DServer::BODY_PARAM_LINEAR_DAMP: {
return linear_damp;
} break;
case Physics2DServer::BODY_PARAM_ANGULAR_DAMP: {
return angular_damp;
} break;
default:{}
}
return 0;
}
void Body2DSW::set_mode(Physics2DServer::BodyMode p_mode) {
Physics2DServer::BodyMode prev=mode;
mode=p_mode;
switch(p_mode) {
//CLEAR UP EVERYTHING IN CASE IT NOT WORKS!
case Physics2DServer::BODY_MODE_STATIC:
case Physics2DServer::BODY_MODE_KINEMATIC: {
_set_inv_transform(get_transform().affine_inverse());
_inv_mass=0;
_set_static(p_mode==Physics2DServer::BODY_MODE_STATIC);
set_active(p_mode==Physics2DServer::BODY_MODE_KINEMATIC && contacts.size());
linear_velocity=Vector2();
angular_velocity=0;
if (mode==Physics2DServer::BODY_MODE_KINEMATIC && prev!=mode) {
first_time_kinematic=true;
}
} break;
case Physics2DServer::BODY_MODE_RIGID: {
_inv_mass=mass>0?(1.0/mass):0;
_set_static(false);
} break;
case Physics2DServer::BODY_MODE_CHARACTER: {
_inv_mass=mass>0?(1.0/mass):0;
_set_static(false);
} break;
}
_update_inertia();
//if (get_space())
// _update_queries();
}
Physics2DServer::BodyMode Body2DSW::get_mode() const {
return mode;
}
void Body2DSW::_shapes_changed() {
_update_inertia();
wakeup_neighbours();
}
void Body2DSW::set_state(Physics2DServer::BodyState p_state, const Variant& p_variant) {
switch(p_state) {
case Physics2DServer::BODY_STATE_TRANSFORM: {
if (mode==Physics2DServer::BODY_MODE_KINEMATIC) {
new_transform=p_variant;
//wakeup_neighbours();
set_active(true);
if (first_time_kinematic) {
_set_transform(p_variant);
_set_inv_transform(get_transform().affine_inverse());
first_time_kinematic=false;
}
} else if (mode==Physics2DServer::BODY_MODE_STATIC) {
_set_transform(p_variant);
_set_inv_transform(get_transform().affine_inverse());
wakeup_neighbours();
} else {
Matrix32 t = p_variant;
t.orthonormalize();
new_transform=get_transform(); //used as old to compute motion
if (t==new_transform)
break;
_set_transform(t);
_set_inv_transform(get_transform().inverse());
}
wakeup();
} break;
case Physics2DServer::BODY_STATE_LINEAR_VELOCITY: {
//if (mode==Physics2DServer::BODY_MODE_STATIC)
// break;
linear_velocity=p_variant;
wakeup();
} break;
case Physics2DServer::BODY_STATE_ANGULAR_VELOCITY: {
//if (mode!=Physics2DServer::BODY_MODE_RIGID)
// break;
angular_velocity=p_variant;
wakeup();
} break;
case Physics2DServer::BODY_STATE_SLEEPING: {
//?
if (mode==Physics2DServer::BODY_MODE_STATIC || mode==Physics2DServer::BODY_MODE_KINEMATIC)
break;
bool do_sleep=p_variant;
if (do_sleep) {
linear_velocity=Vector2();
//biased_linear_velocity=Vector3();
angular_velocity=0;
//biased_angular_velocity=Vector3();
set_active(false);
} else {
if (mode!=Physics2DServer::BODY_MODE_STATIC)
set_active(true);
}
} break;
case Physics2DServer::BODY_STATE_CAN_SLEEP: {
can_sleep=p_variant;
if (mode==Physics2DServer::BODY_MODE_RIGID && !active && !can_sleep)
set_active(true);
} break;
}
}
Variant Body2DSW::get_state(Physics2DServer::BodyState p_state) const {
switch(p_state) {
case Physics2DServer::BODY_STATE_TRANSFORM: {
return get_transform();
} break;
case Physics2DServer::BODY_STATE_LINEAR_VELOCITY: {
return linear_velocity;
} break;
case Physics2DServer::BODY_STATE_ANGULAR_VELOCITY: {
return angular_velocity;
} break;
case Physics2DServer::BODY_STATE_SLEEPING: {
return !is_active();
} break;
case Physics2DServer::BODY_STATE_CAN_SLEEP: {
return can_sleep;
} break;
}
return Variant();
}
void Body2DSW::set_space(Space2DSW *p_space){
if (get_space()) {
wakeup_neighbours();
if (inertia_update_list.in_list())
get_space()->body_remove_from_inertia_update_list(&inertia_update_list);
if (active_list.in_list())
get_space()->body_remove_from_active_list(&active_list);
if (direct_state_query_list.in_list())
get_space()->body_remove_from_state_query_list(&direct_state_query_list);
}
_set_space(p_space);
if (get_space()) {
_update_inertia();
if (active)
get_space()->body_add_to_active_list(&active_list);
// _update_queries();
//if (is_active()) {
// active=false;
// set_active(true);
//}
}
first_integration=false;
}
void Body2DSW::_compute_area_gravity_and_dampenings(const Area2DSW *p_area) {
if (p_area->is_gravity_point()) {
if(p_area->get_gravity_distance_scale() > 0) {
Vector2 v = p_area->get_transform().xform(p_area->get_gravity_vector()) - get_transform().get_origin();
gravity += v.normalized() * (p_area->get_gravity() / Math::pow(v.length() * p_area->get_gravity_distance_scale()+1, 2) );
} else {
gravity += (p_area->get_transform().xform(p_area->get_gravity_vector()) - get_transform().get_origin()).normalized() * p_area->get_gravity();
}
} else {
gravity += p_area->get_gravity_vector() * p_area->get_gravity();
}
area_linear_damp += p_area->get_linear_damp();
area_angular_damp += p_area->get_angular_damp();
}
void Body2DSW::integrate_forces(real_t p_step) {
if (mode==Physics2DServer::BODY_MODE_STATIC)
return;
Area2DSW *def_area = get_space()->get_default_area();
// Area2DSW *damp_area = def_area;
ERR_FAIL_COND(!def_area);
int ac = areas.size();
bool stopped = false;
gravity = Vector2(0,0);
area_angular_damp = 0;
area_linear_damp = 0;
if (ac) {
areas.sort();
const AreaCMP *aa = &areas[0];
// damp_area = aa[ac-1].area;
for(int i=ac-1;i>=0 && !stopped;i--) {
Physics2DServer::AreaSpaceOverrideMode mode=aa[i].area->get_space_override_mode();
switch (mode) {
case Physics2DServer::AREA_SPACE_OVERRIDE_COMBINE:
case Physics2DServer::AREA_SPACE_OVERRIDE_COMBINE_REPLACE: {
_compute_area_gravity_and_dampenings(aa[i].area);
stopped = mode==Physics2DServer::AREA_SPACE_OVERRIDE_COMBINE_REPLACE;
} break;
case Physics2DServer::AREA_SPACE_OVERRIDE_REPLACE:
case Physics2DServer::AREA_SPACE_OVERRIDE_REPLACE_COMBINE: {
gravity = Vector2(0,0);
area_angular_damp = 0;
area_linear_damp = 0;
_compute_area_gravity_and_dampenings(aa[i].area);
stopped = mode==Physics2DServer::AREA_SPACE_OVERRIDE_REPLACE;
} break;
default: {}
}
}
}
if( !stopped ) {
_compute_area_gravity_and_dampenings(def_area);
}
gravity*=gravity_scale;
// If less than 0, override dampenings with that of the Body2D
if (angular_damp>=0)
area_angular_damp = angular_damp;
//else
// area_angular_damp=damp_area->get_angular_damp();
if (linear_damp>=0)
area_linear_damp = linear_damp;
//else
// area_linear_damp=damp_area->get_linear_damp();
Vector2 motion;
bool do_motion=false;
if (mode==Physics2DServer::BODY_MODE_KINEMATIC) {
//compute motion, angular and etc. velocities from prev transform
linear_velocity = (new_transform.elements[2] - get_transform().elements[2])/p_step;
real_t rot = new_transform.affine_inverse().basis_xform(get_transform().elements[1]).angle();
angular_velocity = rot / p_step;
motion = new_transform.elements[2] - get_transform().elements[2];
do_motion=true;
//for(int i=0;i<get_shape_count();i++) {
// set_shape_kinematic_advance(i,Vector2());
// set_shape_kinematic_retreat(i,0);
//}
} else {
if (!omit_force_integration && !first_integration) {
//overriden by direct state query
Vector2 force=gravity*mass;
force+=applied_force;
real_t torque=applied_torque;
real_t damp = 1.0 - p_step * area_linear_damp;
if (damp<0) // reached zero in the given time
damp=0;
real_t angular_damp = 1.0 - p_step * area_angular_damp;
if (angular_damp<0) // reached zero in the given time
angular_damp=0;
linear_velocity*=damp;
angular_velocity*=angular_damp;
linear_velocity+=_inv_mass * force * p_step;
angular_velocity+=_inv_inertia * torque * p_step;
}
if (continuous_cd_mode!=Physics2DServer::CCD_MODE_DISABLED) {
motion = new_transform.get_origin() - get_transform().get_origin();
//linear_velocity*p_step;
do_motion=true;
}
}
//motion=linear_velocity*p_step;
first_integration=false;
biased_angular_velocity=0;
biased_linear_velocity=Vector2();
if (do_motion) {//shapes temporarily extend for raycast
_update_shapes_with_motion(motion);
}
// damp_area=NULL; // clear the area, so it is set in the next frame
def_area=NULL; // clear the area, so it is set in the next frame
contact_count=0;
}
void Body2DSW::integrate_velocities(real_t p_step) {
if (mode==Physics2DServer::BODY_MODE_STATIC)
return;
if (fi_callback)
get_space()->body_add_to_state_query_list(&direct_state_query_list);
if (mode==Physics2DServer::BODY_MODE_KINEMATIC) {
_set_transform(new_transform,false);
_set_inv_transform(new_transform.affine_inverse());
if (contacts.size()==0 && linear_velocity==Vector2() && angular_velocity==0)
set_active(false); //stopped moving, deactivate
return;
}
real_t total_angular_velocity = angular_velocity+biased_angular_velocity;
Vector2 total_linear_velocity=linear_velocity+biased_linear_velocity;
real_t angle = get_transform().get_rotation() - total_angular_velocity * p_step;
Vector2 pos = get_transform().get_origin() + total_linear_velocity * p_step;
_set_transform(Matrix32(angle,pos),continuous_cd_mode==Physics2DServer::CCD_MODE_DISABLED);
_set_inv_transform(get_transform().inverse());
if (continuous_cd_mode!=Physics2DServer::CCD_MODE_DISABLED)
new_transform=get_transform();
//_update_inertia_tensor();
}
void Body2DSW::wakeup_neighbours() {
for(Map<Constraint2DSW*,int>::Element *E=constraint_map.front();E;E=E->next()) {
const Constraint2DSW *c=E->key();
Body2DSW **n = c->get_body_ptr();
int bc=c->get_body_count();
for(int i=0;i<bc;i++) {
if (i==E->get())
continue;
Body2DSW *b = n[i];
if (b->mode!=Physics2DServer::BODY_MODE_RIGID)
continue;
if (!b->is_active())
b->set_active(true);
}
}
}
void Body2DSW::call_queries() {
if (fi_callback) {
Physics2DDirectBodyStateSW *dbs = Physics2DDirectBodyStateSW::singleton;
dbs->body=this;
Variant v=dbs;
const Variant *vp[2]={&v,&fi_callback->callback_udata};
Object *obj = ObjectDB::get_instance(fi_callback->id);
if (!obj) {
set_force_integration_callback(0,StringName());
} else {
Variant::CallError ce;
if (fi_callback->callback_udata.get_type()) {
obj->call(fi_callback->method,vp,2,ce);
} else {
obj->call(fi_callback->method,vp,1,ce);
}
}
}
}
bool Body2DSW::sleep_test(real_t p_step) {
if (mode==Physics2DServer::BODY_MODE_STATIC || mode==Physics2DServer::BODY_MODE_KINEMATIC)
return true; //
else if (mode==Physics2DServer::BODY_MODE_CHARACTER)
return !active; // characters and kinematic bodies don't sleep unless asked to sleep
else if (!can_sleep)
return false;
if (Math::abs(angular_velocity)<get_space()->get_body_angular_velocity_sleep_treshold() && Math::abs(linear_velocity.length_squared()) < get_space()->get_body_linear_velocity_sleep_treshold()*get_space()->get_body_linear_velocity_sleep_treshold()) {
still_time+=p_step;
return still_time > get_space()->get_body_time_to_sleep();
} else {
still_time=0; //maybe this should be set to 0 on set_active?
return false;
}
}
void Body2DSW::set_force_integration_callback(ObjectID p_id,const StringName& p_method,const Variant& p_udata) {
if (fi_callback) {
memdelete(fi_callback);
fi_callback=NULL;
}
if (p_id!=0) {
fi_callback=memnew(ForceIntegrationCallback);
fi_callback->id=p_id;
fi_callback->method=p_method;
fi_callback->callback_udata=p_udata;
}
}
Body2DSW::Body2DSW() : CollisionObject2DSW(TYPE_BODY), active_list(this), inertia_update_list(this), direct_state_query_list(this) {
mode=Physics2DServer::BODY_MODE_RIGID;
active=true;
angular_velocity=0;
biased_angular_velocity=0;
mass=1;
_inv_inertia=0;
_inv_mass=1;
bounce=0;
friction=1;
omit_force_integration=false;
applied_torque=0;
island_step=0;
island_next=NULL;
island_list_next=NULL;
_set_static(false);
first_time_kinematic=false;
linear_damp=-1;
angular_damp=-1;
area_angular_damp=0;
area_linear_damp=0;
contact_count=0;
gravity_scale=1.0;
using_one_way_cache=false;
one_way_collision_max_depth=0.1;
first_integration=false;
still_time=0;
continuous_cd_mode=Physics2DServer::CCD_MODE_DISABLED;
can_sleep=false;
fi_callback=NULL;
}
Body2DSW::~Body2DSW() {
if (fi_callback)
memdelete(fi_callback);
}
Physics2DDirectBodyStateSW *Physics2DDirectBodyStateSW::singleton=NULL;
Physics2DDirectSpaceState* Physics2DDirectBodyStateSW::get_space_state() {
return body->get_space()->get_direct_state();
}
Variant Physics2DDirectBodyStateSW::get_contact_collider_shape_metadata(int p_contact_idx) const {
ERR_FAIL_INDEX_V(p_contact_idx,body->contact_count,Variant());
if (!Physics2DServerSW::singletonsw->body_owner.owns(body->contacts[p_contact_idx].collider)) {
return Variant();
}
Body2DSW *other = Physics2DServerSW::singletonsw->body_owner.get(body->contacts[p_contact_idx].collider);
int sidx = body->contacts[p_contact_idx].collider_shape;
if (sidx<0 || sidx>=other->get_shape_count()) {
return Variant();
}
return other->get_shape_metadata(sidx);
}