virtualx-engine/servers/physics_2d/broad_phase_2d_hash_grid.cpp
Rémi Verschelde 1426cd3b3a
One Copyright Update to rule them all
As many open source projects have started doing it, we're removing the
current year from the copyright notice, so that we don't need to bump
it every year.

It seems like only the first year of publication is technically
relevant for copyright notices, and even that seems to be something
that many companies stopped listing altogether (in a version controlled
codebase, the commits are a much better source of date of publication
than a hardcoded copyright statement).

We also now list Godot Engine contributors first as we're collectively
the current maintainers of the project, and we clarify that the
"exclusive" copyright of the co-founders covers the timespan before
opensourcing (their further contributions are included as part of Godot
Engine contributors).

Also fixed "cf." Frenchism - it's meant as "refer to / see".

Backported from #70885.
2023-01-10 15:26:54 +01:00

653 lines
18 KiB
C++

/**************************************************************************/
/* broad_phase_2d_hash_grid.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 */
/* 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 "broad_phase_2d_hash_grid.h"
#include "collision_object_2d_sw.h"
#include "core/project_settings.h"
#define LARGE_ELEMENT_FI 1.01239812
void BroadPhase2DHashGrid::_pair_attempt(Element *p_elem, Element *p_with) {
if (p_elem->owner == p_with->owner) {
return;
}
if (!_test_collision_mask(p_elem->collision_mask, p_elem->collision_layer, p_with->collision_mask, p_with->collision_layer)) {
return;
}
Map<Element *, PairData *>::Element *E = p_elem->paired.find(p_with);
ERR_FAIL_COND(p_elem->_static && p_with->_static);
if (!E) {
PairData *pd = memnew(PairData);
p_elem->paired[p_with] = pd;
p_with->paired[p_elem] = pd;
} else {
E->get()->rc++;
}
}
void BroadPhase2DHashGrid::_unpair_attempt(Element *p_elem, Element *p_with) {
if (p_elem->owner == p_with->owner) {
return;
}
if (!_test_collision_mask(p_elem->collision_mask, p_elem->collision_layer, p_with->collision_mask, p_with->collision_layer)) {
return;
}
Map<Element *, PairData *>::Element *E = p_elem->paired.find(p_with);
ERR_FAIL_COND(!E); //this should really be paired..
E->get()->rc--;
if (E->get()->rc == 0) {
if (E->get()->colliding) {
//uncollide
if (unpair_callback) {
unpair_callback(p_elem->owner, p_elem->subindex, p_with->owner, p_with->subindex, E->get()->ud, unpair_userdata);
}
}
memdelete(E->get());
p_elem->paired.erase(E);
p_with->paired.erase(p_elem);
}
}
void BroadPhase2DHashGrid::_check_motion(Element *p_elem) {
for (Map<Element *, PairData *>::Element *E = p_elem->paired.front(); E; E = E->next()) {
bool physical_collision = p_elem->aabb.intersects(E->key()->aabb);
bool logical_collision = p_elem->owner->test_collision_mask(E->key()->owner);
if (physical_collision && logical_collision) {
if (!E->get()->colliding && pair_callback) {
E->get()->ud = pair_callback(p_elem->owner, p_elem->subindex, E->key()->owner, E->key()->subindex, nullptr, pair_userdata);
}
E->get()->colliding = true;
} else { // No collision
if (E->get()->colliding && unpair_callback) {
unpair_callback(p_elem->owner, p_elem->subindex, E->key()->owner, E->key()->subindex, E->get()->ud, unpair_userdata);
E->get()->ud = nullptr;
}
E->get()->colliding = false;
}
}
}
void BroadPhase2DHashGrid::_enter_grid(Element *p_elem, const Rect2 &p_rect, bool p_static, bool p_force_enter) {
Vector2 sz = (p_rect.size / cell_size * LARGE_ELEMENT_FI); //use magic number to avoid floating point issues
if (sz.width * sz.height > large_object_min_surface) {
//large object, do not use grid, must check against all elements
for (Map<ID, Element>::Element *E = element_map.front(); E; E = E->next()) {
if (E->key() == p_elem->self) {
continue; // do not pair against itself
}
if (E->get()._static && p_static) {
continue;
}
_pair_attempt(p_elem, &E->get());
}
large_elements[p_elem].inc();
return;
}
Point2i from = (p_rect.position / cell_size).floor();
Point2i to = ((p_rect.position + p_rect.size) / cell_size).floor();
for (int i = from.x; i <= to.x; i++) {
for (int j = from.y; j <= to.y; j++) {
PosKey pk;
pk.x = i;
pk.y = j;
uint32_t idx = pk.hash() % hash_table_size;
PosBin *pb = hash_table[idx];
while (pb) {
if (pb->key == pk) {
break;
}
pb = pb->next;
}
bool entered = p_force_enter;
if (!pb) {
//does not exist, create!
pb = memnew(PosBin);
pb->key = pk;
pb->next = hash_table[idx];
hash_table[idx] = pb;
}
if (p_static) {
if (pb->static_object_set[p_elem].inc() == 1) {
entered = true;
}
} else {
if (pb->object_set[p_elem].inc() == 1) {
entered = true;
}
}
if (entered) {
for (Map<Element *, RC>::Element *E = pb->object_set.front(); E; E = E->next()) {
_pair_attempt(p_elem, E->key());
}
if (!p_static) {
for (Map<Element *, RC>::Element *E = pb->static_object_set.front(); E; E = E->next()) {
_pair_attempt(p_elem, E->key());
}
}
}
}
}
//pair separatedly with large elements
for (Map<Element *, RC>::Element *E = large_elements.front(); E; E = E->next()) {
if (E->key() == p_elem) {
continue; // do not pair against itself
}
if (E->key()->_static && p_static) {
continue;
}
_pair_attempt(E->key(), p_elem);
}
}
void BroadPhase2DHashGrid::_exit_grid(Element *p_elem, const Rect2 &p_rect, bool p_static, bool p_force_exit) {
Vector2 sz = (p_rect.size / cell_size * LARGE_ELEMENT_FI);
if (sz.width * sz.height > large_object_min_surface) {
//unpair all elements, instead of checking all, just check what is already paired, so we at least save from checking static vs static
Map<Element *, PairData *>::Element *E = p_elem->paired.front();
while (E) {
Map<Element *, PairData *>::Element *next = E->next();
_unpair_attempt(p_elem, E->key());
E = next;
}
if (large_elements[p_elem].dec() == 0) {
large_elements.erase(p_elem);
}
return;
}
Point2i from = (p_rect.position / cell_size).floor();
Point2i to = ((p_rect.position + p_rect.size) / cell_size).floor();
for (int i = from.x; i <= to.x; i++) {
for (int j = from.y; j <= to.y; j++) {
PosKey pk;
pk.x = i;
pk.y = j;
uint32_t idx = pk.hash() % hash_table_size;
PosBin *pb = hash_table[idx];
while (pb) {
if (pb->key == pk) {
break;
}
pb = pb->next;
}
ERR_CONTINUE(!pb); //should exist!!
bool exited = p_force_exit;
if (p_static) {
if (pb->static_object_set[p_elem].dec() == 0) {
pb->static_object_set.erase(p_elem);
exited = true;
}
} else {
if (pb->object_set[p_elem].dec() == 0) {
pb->object_set.erase(p_elem);
exited = true;
}
}
if (exited) {
for (Map<Element *, RC>::Element *E = pb->object_set.front(); E; E = E->next()) {
_unpair_attempt(p_elem, E->key());
}
if (!p_static) {
for (Map<Element *, RC>::Element *E = pb->static_object_set.front(); E; E = E->next()) {
_unpair_attempt(p_elem, E->key());
}
}
}
if (pb->object_set.empty() && pb->static_object_set.empty()) {
if (hash_table[idx] == pb) {
hash_table[idx] = pb->next;
} else {
PosBin *px = hash_table[idx];
while (px) {
if (px->next == pb) {
px->next = pb->next;
break;
}
px = px->next;
}
ERR_CONTINUE(!px);
}
memdelete(pb);
}
}
}
for (Map<Element *, RC>::Element *E = large_elements.front(); E; E = E->next()) {
if (E->key() == p_elem) {
continue; // do not pair against itself
}
if (E->key()->_static && p_static) {
continue;
}
//unpair from large elements
_unpair_attempt(p_elem, E->key());
}
}
BroadPhase2DHashGrid::ID BroadPhase2DHashGrid::create(CollisionObject2DSW *p_object, int p_subindex, const Rect2 &p_aabb, bool p_static) {
current++;
Element e;
e.owner = p_object;
e._static = false;
e.collision_mask = p_object->get_collision_mask();
e.collision_layer = p_object->get_collision_layer();
e.subindex = p_subindex;
e.self = current;
e.pass = 0;
element_map[current] = e;
return current;
}
void BroadPhase2DHashGrid::move(ID p_id, const Rect2 &p_aabb) {
Map<ID, Element>::Element *E = element_map.find(p_id);
ERR_FAIL_COND(!E);
Element &e = E->get();
bool layer_changed = e.collision_mask != e.owner->get_collision_mask() || e.collision_layer != e.owner->get_collision_layer();
if (p_aabb != e.aabb || layer_changed) {
uint32_t old_mask = e.collision_mask;
uint32_t old_layer = e.collision_layer;
if (p_aabb != Rect2()) {
e.collision_mask = e.owner->get_collision_mask();
e.collision_layer = e.owner->get_collision_layer();
_enter_grid(&e, p_aabb, e._static, layer_changed);
}
if (e.aabb != Rect2()) {
// Need _exit_grid to remove from cells based on the old layer values.
e.collision_mask = old_mask;
e.collision_layer = old_layer;
_exit_grid(&e, e.aabb, e._static, layer_changed);
e.collision_mask = e.owner->get_collision_mask();
e.collision_layer = e.owner->get_collision_layer();
}
e.aabb = p_aabb;
}
_check_motion(&e);
}
void BroadPhase2DHashGrid::recheck_pairs(ID p_id) {
Map<ID, Element>::Element *E = element_map.find(p_id);
ERR_FAIL_COND(!E);
Element &e = E->get();
move(p_id, e.aabb);
}
void BroadPhase2DHashGrid::set_static(ID p_id, bool p_static) {
Map<ID, Element>::Element *E = element_map.find(p_id);
ERR_FAIL_COND(!E);
Element &e = E->get();
if (e._static == p_static) {
return;
}
if (e.aabb != Rect2()) {
_exit_grid(&e, e.aabb, e._static, false);
}
e._static = p_static;
if (e.aabb != Rect2()) {
_enter_grid(&e, e.aabb, e._static, false);
_check_motion(&e);
}
}
void BroadPhase2DHashGrid::remove(ID p_id) {
Map<ID, Element>::Element *E = element_map.find(p_id);
ERR_FAIL_COND(!E);
Element &e = E->get();
if (e.aabb != Rect2()) {
_exit_grid(&e, e.aabb, e._static, false);
}
element_map.erase(p_id);
}
CollisionObject2DSW *BroadPhase2DHashGrid::get_object(ID p_id) const {
const Map<ID, Element>::Element *E = element_map.find(p_id);
ERR_FAIL_COND_V(!E, nullptr);
return E->get().owner;
}
bool BroadPhase2DHashGrid::is_static(ID p_id) const {
const Map<ID, Element>::Element *E = element_map.find(p_id);
ERR_FAIL_COND_V(!E, false);
return E->get()._static;
}
int BroadPhase2DHashGrid::get_subindex(ID p_id) const {
const Map<ID, Element>::Element *E = element_map.find(p_id);
ERR_FAIL_COND_V(!E, -1);
return E->get().subindex;
}
template <bool use_aabb, bool use_segment>
void BroadPhase2DHashGrid::_cull(const Point2i p_cell, const Rect2 &p_aabb, const Point2 &p_from, const Point2 &p_to, CollisionObject2DSW **p_results, int p_max_results, int *p_result_indices, int &index) {
PosKey pk;
pk.x = p_cell.x;
pk.y = p_cell.y;
uint32_t idx = pk.hash() % hash_table_size;
PosBin *pb = hash_table[idx];
while (pb) {
if (pb->key == pk) {
break;
}
pb = pb->next;
}
if (!pb) {
return;
}
for (Map<Element *, RC>::Element *E = pb->object_set.front(); E; E = E->next()) {
if (index >= p_max_results) {
break;
}
if (E->key()->pass == pass) {
continue;
}
E->key()->pass = pass;
if (use_aabb && !p_aabb.intersects(E->key()->aabb)) {
continue;
}
if (use_segment && !E->key()->aabb.intersects_segment(p_from, p_to)) {
continue;
}
p_results[index] = E->key()->owner;
p_result_indices[index] = E->key()->subindex;
index++;
}
for (Map<Element *, RC>::Element *E = pb->static_object_set.front(); E; E = E->next()) {
if (index >= p_max_results) {
break;
}
if (E->key()->pass == pass) {
continue;
}
if (use_aabb && !p_aabb.intersects(E->key()->aabb)) {
continue;
}
if (use_segment && !E->key()->aabb.intersects_segment(p_from, p_to)) {
continue;
}
E->key()->pass = pass;
p_results[index] = E->key()->owner;
p_result_indices[index] = E->key()->subindex;
index++;
}
}
int BroadPhase2DHashGrid::cull_segment(const Vector2 &p_from, const Vector2 &p_to, CollisionObject2DSW **p_results, int p_max_results, int *p_result_indices) {
pass++;
Vector2 dir = (p_to - p_from);
if (dir == Vector2()) {
return 0;
}
//avoid divisions by zero
dir.normalize();
if (dir.x == 0.0) {
dir.x = 0.000001;
}
if (dir.y == 0.0) {
dir.y = 0.000001;
}
Vector2 delta = dir.abs();
delta.x = cell_size / delta.x;
delta.y = cell_size / delta.y;
Point2i pos = (p_from / cell_size).floor();
Point2i end = (p_to / cell_size).floor();
Point2i step = Vector2(SGN(dir.x), SGN(dir.y));
Vector2 max;
if (dir.x < 0) {
max.x = (Math::floor((double)pos.x) * cell_size - p_from.x) / dir.x;
} else {
max.x = (Math::floor((double)pos.x + 1) * cell_size - p_from.x) / dir.x;
}
if (dir.y < 0) {
max.y = (Math::floor((double)pos.y) * cell_size - p_from.y) / dir.y;
} else {
max.y = (Math::floor((double)pos.y + 1) * cell_size - p_from.y) / dir.y;
}
int cullcount = 0;
_cull<false, true>(pos, Rect2(), p_from, p_to, p_results, p_max_results, p_result_indices, cullcount);
bool reached_x = false;
bool reached_y = false;
while (true) {
if (max.x < max.y) {
max.x += delta.x;
pos.x += step.x;
} else {
max.y += delta.y;
pos.y += step.y;
}
if (step.x > 0) {
if (pos.x >= end.x) {
reached_x = true;
}
} else if (pos.x <= end.x) {
reached_x = true;
}
if (step.y > 0) {
if (pos.y >= end.y) {
reached_y = true;
}
} else if (pos.y <= end.y) {
reached_y = true;
}
_cull<false, true>(pos, Rect2(), p_from, p_to, p_results, p_max_results, p_result_indices, cullcount);
if (reached_x && reached_y) {
break;
}
}
for (Map<Element *, RC>::Element *E = large_elements.front(); E; E = E->next()) {
if (cullcount >= p_max_results) {
break;
}
if (E->key()->pass == pass) {
continue;
}
E->key()->pass = pass;
/*
if (use_aabb && !p_aabb.intersects(E->key()->aabb))
continue;
*/
if (!E->key()->aabb.intersects_segment(p_from, p_to)) {
continue;
}
p_results[cullcount] = E->key()->owner;
p_result_indices[cullcount] = E->key()->subindex;
cullcount++;
}
return cullcount;
}
int BroadPhase2DHashGrid::cull_aabb(const Rect2 &p_aabb, CollisionObject2DSW **p_results, int p_max_results, int *p_result_indices) {
pass++;
Point2i from = (p_aabb.position / cell_size).floor();
Point2i to = ((p_aabb.position + p_aabb.size) / cell_size).floor();
int cullcount = 0;
for (int i = from.x; i <= to.x; i++) {
for (int j = from.y; j <= to.y; j++) {
_cull<true, false>(Point2i(i, j), p_aabb, Point2(), Point2(), p_results, p_max_results, p_result_indices, cullcount);
}
}
for (Map<Element *, RC>::Element *E = large_elements.front(); E; E = E->next()) {
if (cullcount >= p_max_results) {
break;
}
if (E->key()->pass == pass) {
continue;
}
E->key()->pass = pass;
if (!p_aabb.intersects(E->key()->aabb)) {
continue;
}
/*
if (!E->key()->aabb.intersects_segment(p_from,p_to))
continue;
*/
p_results[cullcount] = E->key()->owner;
p_result_indices[cullcount] = E->key()->subindex;
cullcount++;
}
return cullcount;
}
void BroadPhase2DHashGrid::set_pair_callback(PairCallback p_pair_callback, void *p_userdata) {
pair_callback = p_pair_callback;
pair_userdata = p_userdata;
}
void BroadPhase2DHashGrid::set_unpair_callback(UnpairCallback p_unpair_callback, void *p_userdata) {
unpair_callback = p_unpair_callback;
unpair_userdata = p_userdata;
}
void BroadPhase2DHashGrid::update() {
}
BroadPhase2DSW *BroadPhase2DHashGrid::_create() {
return memnew(BroadPhase2DHashGrid);
}
BroadPhase2DHashGrid::BroadPhase2DHashGrid() {
hash_table_size = GLOBAL_GET("physics/2d/bp_hash_table_size");
ProjectSettings::get_singleton()->set_custom_property_info("physics/2d/bp_hash_table_size", PropertyInfo(Variant::INT, "physics/2d/bp_hash_table_size", PROPERTY_HINT_RANGE, "0,8192,1,or_greater"));
hash_table_size = Math::larger_prime(hash_table_size);
hash_table = memnew_arr(PosBin *, hash_table_size);
cell_size = GLOBAL_GET("physics/2d/cell_size");
ProjectSettings::get_singleton()->set_custom_property_info("physics/2d/cell_size", PropertyInfo(Variant::INT, "physics/2d/cell_size", PROPERTY_HINT_RANGE, "0,512,1,or_greater"));
large_object_min_surface = GLOBAL_GET("physics/2d/large_object_surface_threshold_in_cells");
ProjectSettings::get_singleton()->set_custom_property_info("physics/2d/large_object_surface_threshold_in_cells", PropertyInfo(Variant::INT, "physics/2d/large_object_surface_threshold_in_cells", PROPERTY_HINT_RANGE, "0,1024,1,or_greater"));
for (uint32_t i = 0; i < hash_table_size; i++) {
hash_table[i] = nullptr;
}
pass = 1;
current = 0;
}
BroadPhase2DHashGrid::~BroadPhase2DHashGrid() {
for (uint32_t i = 0; i < hash_table_size; i++) {
while (hash_table[i]) {
PosBin *pb = hash_table[i];
hash_table[i] = pb->next;
memdelete(pb);
}
}
memdelete_arr(hash_table);
}