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#include <algorithm>
#include <cmath>
#include <cstddef>
#include <functional>
#include <optional>
#include <utility>
#include <variant>
#include "../manager/ComponentManager.h"
#include "../manager/EventManager.h"
#include "api/BoxCollider.h"
#include "api/CircleCollider.h"
#include "api/Event.h"
#include "api/Metadata.h"
#include "api/Rigidbody.h"
#include "api/Transform.h"
#include "api/Vector2.h"
#include "util/OptionalRef.h"
#include "util/AbsoluutPosition.h"
#include "Collider.h"
#include "CollisionSystem.h"
#include "types.h"
using namespace crepe;
void CollisionSystem::update() {
std::vector<CollisionInternal> all_colliders;
game_object_id_t id = 0;
ComponentManager & mgr = this->mediator.component_manager;
RefVector<Rigidbody> rigidbodies = mgr.get_components_by_type<Rigidbody>();
// Collisions can only happen on object with a rigidbody
for (Rigidbody & rigidbody : rigidbodies) {
if (!rigidbody.active) continue;
id = rigidbody.game_object_id;
Transform & transform = mgr.get_components_by_id<Transform>(id).front().get();
// Check if the boxcollider is active and has the same id as the rigidbody.
RefVector<BoxCollider> boxcolliders = mgr.get_components_by_type<BoxCollider>();
for (BoxCollider & boxcollider : boxcolliders) {
if (boxcollider.game_object_id != id) continue;
if (!boxcollider.active) continue;
all_colliders.push_back({.id = id,
.collider = collider_variant{boxcollider},
.transform = transform,
.rigidbody = rigidbody});
}
// Check if the circlecollider is active and has the same id as the rigidbody.
RefVector<CircleCollider> circlecolliders
= mgr.get_components_by_type<CircleCollider>();
for (CircleCollider & circlecollider : circlecolliders) {
if (circlecollider.game_object_id != id) continue;
if (!circlecollider.active) continue;
all_colliders.push_back({.id = id,
.collider = collider_variant{circlecollider},
.transform = transform,
.rigidbody = rigidbody});
}
}
// Check between all colliders if there is a collision
std::vector<std::pair<CollisionInternal, CollisionInternal>> collided
= this->gather_collisions(all_colliders);
// For both objects call the collision handler
for (auto & collision_pair : collided) {
this->collision_handler_request(collision_pair.first, collision_pair.second);
// this->collision_handler_request(collision_pair.second, collision_pair.first);
}
}
void CollisionSystem::collision_handler_request(CollisionInternal & this_data,
CollisionInternal & other_data) {
CollisionInternalType type
= this->get_collider_type(this_data.collider, other_data.collider);
std::pair<vec2, CollisionSystem::Direction> resolution_data
= this->collision_handler(this_data, other_data, type);
ComponentManager & mgr = this->mediator.component_manager;
OptionalRef<Metadata> this_metadata
= mgr.get_components_by_id<Metadata>(this_data.id).front().get();
OptionalRef<Metadata> other_metadata
= mgr.get_components_by_id<Metadata>(other_data.id).front().get();
OptionalRef<Collider> this_collider;
OptionalRef<Collider> other_collider;
switch (type) {
case CollisionInternalType::BOX_BOX: {
this_collider = std::get<std::reference_wrapper<BoxCollider>>(this_data.collider);
other_collider
= std::get<std::reference_wrapper<BoxCollider>>(other_data.collider);
break;
}
case CollisionInternalType::BOX_CIRCLE: {
this_collider = std::get<std::reference_wrapper<BoxCollider>>(this_data.collider);
other_collider
= std::get<std::reference_wrapper<CircleCollider>>(other_data.collider);
break;
}
case CollisionInternalType::CIRCLE_BOX: {
this_collider
= std::get<std::reference_wrapper<CircleCollider>>(this_data.collider);
other_collider
= std::get<std::reference_wrapper<BoxCollider>>(other_data.collider);
break;
}
case CollisionInternalType::CIRCLE_CIRCLE: {
this_collider
= std::get<std::reference_wrapper<CircleCollider>>(this_data.collider);
other_collider
= std::get<std::reference_wrapper<CircleCollider>>(other_data.collider);
break;
}
}
// collision info
crepe::CollisionSystem::CollisionInfo collision_info{
.this_collider = this_collider,
.this_transform = this_data.transform,
.this_rigidbody = this_data.rigidbody,
.this_metadata = this_metadata,
.other_collider = other_collider,
.other_transform = other_data.transform,
.other_rigidbody = other_data.rigidbody,
.other_metadata = other_metadata,
.resolution = resolution_data.first,
.resolution_direction = resolution_data.second,
};
// Determine if static needs to be called
this->determine_collision_handler(collision_info);
}
std::pair<vec2, CollisionSystem::Direction>
CollisionSystem::collision_handler(CollisionInternal & data1, CollisionInternal & data2,
CollisionInternalType type) {
vec2 resolution;
switch (type) {
case CollisionInternalType::BOX_BOX: {
const BoxCollider & collider1
= std::get<std::reference_wrapper<BoxCollider>>(data1.collider);
const BoxCollider & collider2
= std::get<std::reference_wrapper<BoxCollider>>(data2.collider);
vec2 collider_pos1 = AbsoluutPosition::get_position(data1.transform,collider1.offset);
vec2 collider_pos2 = AbsoluutPosition::get_position(data2.transform,collider2.offset);
resolution = this->get_box_box_resolution(collider1, collider2, collider_pos1,
collider_pos2);
break;
}
case CollisionInternalType::BOX_CIRCLE: {
const BoxCollider & collider1
= std::get<std::reference_wrapper<BoxCollider>>(data1.collider);
const CircleCollider & collider2
= std::get<std::reference_wrapper<CircleCollider>>(data2.collider);
vec2 collider_pos1 = AbsoluutPosition::get_position(data1.transform,collider1.offset);
vec2 collider_pos2 = AbsoluutPosition::get_position(data2.transform,collider2.offset);
resolution = -this->get_circle_box_resolution(collider2, collider1, collider_pos2,
collider_pos1);
break;
}
case CollisionInternalType::CIRCLE_CIRCLE: {
const CircleCollider & collider1
= std::get<std::reference_wrapper<CircleCollider>>(data1.collider);
const CircleCollider & collider2
= std::get<std::reference_wrapper<CircleCollider>>(data2.collider);
vec2 collider_pos1 = AbsoluutPosition::get_position(data1.transform,collider1.offset);
vec2 collider_pos2 = AbsoluutPosition::get_position(data2.transform,collider2.offset);
resolution = this->get_circle_circle_resolution(collider1, collider2,
collider_pos1, collider_pos2);
break;
}
case CollisionInternalType::CIRCLE_BOX: {
const CircleCollider & collider1
= std::get<std::reference_wrapper<CircleCollider>>(data1.collider);
const BoxCollider & collider2
= std::get<std::reference_wrapper<BoxCollider>>(data2.collider);
vec2 collider_pos1 = AbsoluutPosition::get_position(data1.transform,collider1.offset);
vec2 collider_pos2 = AbsoluutPosition::get_position(data2.transform,collider2.offset);
resolution = this->get_circle_box_resolution(collider1, collider2, collider_pos1,
collider_pos2);
break;
}
}
Direction resolution_direction = Direction::NONE;
if (resolution.x != 0 && resolution.y != 0) {
resolution_direction = Direction::BOTH;
} else if (resolution.x != 0) {
resolution_direction = Direction::X_DIRECTION;
//checks if the other velocity has a value and if this object moved
if (data1.rigidbody.data.linear_velocity.x != 0
&& data1.rigidbody.data.linear_velocity.y != 0)
resolution.y = -data1.rigidbody.data.linear_velocity.y
* (resolution.x / data1.rigidbody.data.linear_velocity.x);
} else if (resolution.y != 0) {
resolution_direction = Direction::Y_DIRECTION;
//checks if the other velocity has a value and if this object moved
if (data1.rigidbody.data.linear_velocity.x != 0
&& data1.rigidbody.data.linear_velocity.y != 0)
resolution.x = -data1.rigidbody.data.linear_velocity.x
* (resolution.y / data1.rigidbody.data.linear_velocity.y);
}
return std::make_pair(resolution, resolution_direction);
}
vec2 CollisionSystem::get_box_box_resolution(const BoxCollider & box_collider1,
const BoxCollider & box_collider2,
const vec2 & final_position1,
const vec2 & final_position2) const {
vec2 resolution; // Default resolution vector
vec2 delta = final_position2 - final_position1;
// Compute half-dimensions of the boxes
float half_width1 = box_collider1.dimensions.x / 2.0;
float half_height1 = box_collider1.dimensions.y / 2.0;
float half_width2 = box_collider2.dimensions.x / 2.0;
float half_height2 = box_collider2.dimensions.y / 2.0;
// Calculate overlaps along X and Y axes
float overlap_x = (half_width1 + half_width2) - std::abs(delta.x);
float overlap_y = (half_height1 + half_height2) - std::abs(delta.y);
// Check if there is a collision should always be true
if (overlap_x > 0 && overlap_y > 0) {
// Determine the direction of resolution
if (overlap_x < overlap_y) {
// Resolve along the X-axis (smallest overlap)
resolution.x = (delta.x > 0) ? -overlap_x : overlap_x;
} else if (overlap_y < overlap_x) {
// Resolve along the Y-axis (smallest overlap)
resolution.y = (delta.y > 0) ? -overlap_y : overlap_y;
} else {
// Equal overlap, resolve both directions with preference
resolution.x = (delta.x > 0) ? -overlap_x : overlap_x;
resolution.y = (delta.y > 0) ? -overlap_y : overlap_y;
}
}
return resolution;
}
vec2 CollisionSystem::get_circle_circle_resolution(const CircleCollider & circle_collider1,
const CircleCollider & circle_collider2,
const vec2 & final_position1,
const vec2 & final_position2) const {
vec2 delta = final_position2 - final_position1;
// Compute the distance between the two circle centers
float distance = std::sqrt(delta.x * delta.x + delta.y * delta.y);
// Compute the combined radii of the two circles
float combined_radius = circle_collider1.radius + circle_collider2.radius;
// Compute the penetration depth
float penetration_depth = combined_radius - distance;
// Normalize the delta vector to get the collision direction
vec2 collision_normal = delta / distance;
// Compute the resolution vector
vec2 resolution = -collision_normal * penetration_depth;
return resolution;
}
vec2 CollisionSystem::get_circle_box_resolution(const CircleCollider & circle_collider,
const BoxCollider & box_collider,
const vec2 & circle_position,
const vec2 & box_position) const {
vec2 delta = circle_position - box_position;
// Compute half-dimensions of the box
float half_width = box_collider.dimensions.x / 2.0f;
float half_height = box_collider.dimensions.y / 2.0f;
// Clamp circle center to the nearest point on the box
vec2 closest_point;
closest_point.x = std::clamp(delta.x, -half_width, half_width);
closest_point.y = std::clamp(delta.y, -half_height, half_height);
// Find the vector from the circle center to the closest point
vec2 closest_delta = delta - closest_point;
// Normalize the delta to get the collision direction
float distance
= std::sqrt(closest_delta.x * closest_delta.x + closest_delta.y * closest_delta.y);
vec2 collision_normal = closest_delta / distance;
// Compute penetration depth
float penetration_depth = circle_collider.radius - distance;
// Compute the resolution vector
vec2 resolution = collision_normal * penetration_depth;
return resolution;
}
void CollisionSystem::determine_collision_handler(CollisionInfo & info) {
// Inverted collision info
CollisionInfo inverted = {
.this_collider = info.other_collider,
.this_transform = info.other_transform,
.this_rigidbody = info.other_rigidbody,
.this_metadata = info.other_metadata,
.other_collider = info.this_collider,
.other_transform = info.this_transform,
.other_rigidbody = info.this_rigidbody,
.other_metadata = info.this_metadata,
.resolution = -info.resolution,
.resolution_direction = info.resolution_direction,
};
// If both objects are static skip handle call collision script
if(info.this_rigidbody.data.body_type == Rigidbody::BodyType::STATIC && info.other_rigidbody.data.body_type == Rigidbody::BodyType::STATIC) return;
// First body is not dynamic
if(info.this_rigidbody.data.body_type != Rigidbody::BodyType::DYNAMIC)
{
bool static_collision = info.this_rigidbody.data.body_type == Rigidbody::BodyType::STATIC && info.other_rigidbody.data.body_type == Rigidbody::BodyType::DYNAMIC;
bool kinematic_collision = info.this_rigidbody.data.body_type == Rigidbody::BodyType::KINEMATIC && info.other_rigidbody.data.body_type == Rigidbody::BodyType::DYNAMIC && info.this_rigidbody.data.kinematic_collision;
if(static_collision || kinematic_collision){
// Static collision
this->static_collision_handler(inverted);
};
// Call scripts
this->call_collision_events(inverted,info);
return;
}
// Second body is not dynamic
if(info.other_rigidbody.data.body_type != Rigidbody::BodyType::DYNAMIC)
{
bool static_collision = info.other_rigidbody.data.body_type == Rigidbody::BodyType::STATIC;
bool kinematic_collision = info.other_rigidbody.data.body_type == Rigidbody::BodyType::KINEMATIC && info.other_rigidbody.data.kinematic_collision;
if(static_collision || kinematic_collision) this->static_collision_handler(info);
this->call_collision_events(info,inverted);
return;
}
//dynamic
this->dynamic_collision_handler(info);
this->call_collision_events(info,inverted);
}
void CollisionSystem::call_collision_events(CollisionInfo & info,CollisionInfo & info_inverted){
CollisionEvent data(info);
CollisionEvent data_inverted(info_inverted);
EventManager & emgr = this->mediator.event_manager;
emgr.trigger_event<CollisionEvent>(data, info.this_collider.game_object_id);
emgr.trigger_event<CollisionEvent>(data_inverted, info_inverted.this_collider.game_object_id);
}
void CollisionSystem::static_collision_handler(CollisionInfo & info) {
// Move object back using calculate move back value
info.this_transform.position += info.resolution;
switch (info.resolution_direction) {
case Direction::BOTH:
//bounce
if (info.this_rigidbody.data.elastisity_coefficient > 0) {
info.this_rigidbody.data.linear_velocity
= -info.this_rigidbody.data.linear_velocity
* info.this_rigidbody.data.elastisity_coefficient;
}
//stop movement
else {
info.this_rigidbody.data.linear_velocity = {0, 0};
}
break;
case Direction::Y_DIRECTION:
// Bounce
if (info.this_rigidbody.data.elastisity_coefficient > 0) {
info.this_rigidbody.data.linear_velocity.y
= -info.this_rigidbody.data.linear_velocity.y
* info.this_rigidbody.data.elastisity_coefficient;
}
// Stop movement
else {
info.this_rigidbody.data.linear_velocity.y = 0;
info.this_transform.position.x -= info.resolution.x;
}
break;
case Direction::X_DIRECTION:
// Bounce
if (info.this_rigidbody.data.elastisity_coefficient > 0) {
info.this_rigidbody.data.linear_velocity.x
= -info.this_rigidbody.data.linear_velocity.x
* info.this_rigidbody.data.elastisity_coefficient;
}
// Stop movement
else {
info.this_rigidbody.data.linear_velocity.x = 0;
info.this_transform.position.y -= info.resolution.y;
}
break;
case Direction::NONE:
// Not possible
break;
}
}
void CollisionSystem::dynamic_collision_handler(CollisionInfo & info){
info.this_transform.position += info.resolution/2;
info.other_transform.position += -(info.resolution/2);
switch (info.resolution_direction) {
case Direction::BOTH:
if (info.this_rigidbody.data.elastisity_coefficient > 0) {
info.this_rigidbody.data.linear_velocity
= -info.this_rigidbody.data.linear_velocity
* info.this_rigidbody.data.elastisity_coefficient;
}
else {
info.this_rigidbody.data.linear_velocity = {0, 0};
}
if (info.other_rigidbody.data.elastisity_coefficient > 0) {
info.other_rigidbody.data.linear_velocity
= -info.other_rigidbody.data.linear_velocity
* info.other_rigidbody.data.elastisity_coefficient;
}
else {
info.other_rigidbody.data.linear_velocity = {0, 0};
}
break;
case Direction::Y_DIRECTION:
if (info.this_rigidbody.data.elastisity_coefficient > 0) {
info.this_rigidbody.data.linear_velocity.y
= -info.this_rigidbody.data.linear_velocity.y
* info.this_rigidbody.data.elastisity_coefficient;
}
// Stop movement
else {
info.this_rigidbody.data.linear_velocity.y = 0;
info.this_transform.position.x -= info.resolution.x;
}
if (info.other_rigidbody.data.elastisity_coefficient > 0) {
info.other_rigidbody.data.linear_velocity.y
= -info.other_rigidbody.data.linear_velocity.y
* info.other_rigidbody.data.elastisity_coefficient;
}
// Stop movement
else {
info.other_rigidbody.data.linear_velocity.y = 0;
info.other_transform.position.x -= info.resolution.x;
}
break;
case Direction::X_DIRECTION:
if (info.this_rigidbody.data.elastisity_coefficient > 0) {
info.this_rigidbody.data.linear_velocity.x
= -info.this_rigidbody.data.linear_velocity.x
* info.this_rigidbody.data.elastisity_coefficient;
}
// Stop movement
else {
info.this_rigidbody.data.linear_velocity.x = 0;
info.this_transform.position.y -= info.resolution.y;
}
if (info.other_rigidbody.data.elastisity_coefficient > 0) {
info.other_rigidbody.data.linear_velocity.x
= -info.other_rigidbody.data.linear_velocity.x
* info.other_rigidbody.data.elastisity_coefficient;
}
// Stop movement
else {
info.other_rigidbody.data.linear_velocity.x = 0;
info.other_transform.position.y -= info.resolution.y;
}
break;
case Direction::NONE:
// Not possible
break;
}
}
std::vector<std::pair<CollisionSystem::CollisionInternal, CollisionSystem::CollisionInternal>>
CollisionSystem::gather_collisions(std::vector<CollisionInternal> & colliders) {
// TODO:
// If no colliders skip
// Check if colliders has rigidbody if not skip
// TODO:
// If amount is higer than lets say 16 for now use quadtree otwerwise skip
// Quadtree code
// Quadtree is placed over the input vector
// Return data of collided colliders which are variants
std::vector<std::pair<CollisionInternal, CollisionInternal>> collisions_ret;
//using visit to visit the variant to access the active and id.
for (size_t i = 0; i < colliders.size(); ++i) {
for (size_t j = i + 1; j < colliders.size(); ++j) {
if (colliders[i].id == colliders[j].id) continue;
if (!have_common_layer(colliders[i].rigidbody.data.collision_layers,
colliders[j].rigidbody.data.collision_layers))
continue;
CollisionInternalType type
= get_collider_type(colliders[i].collider, colliders[j].collider);
if (!get_collision(
{
.collider = colliders[i].collider,
.transform = colliders[i].transform,
.rigidbody = colliders[i].rigidbody,
},
{
.collider = colliders[j].collider,
.transform = colliders[j].transform,
.rigidbody = colliders[j].rigidbody,
},
type))
continue;
collisions_ret.emplace_back(colliders[i], colliders[j]);
}
}
return collisions_ret;
}
bool CollisionSystem::have_common_layer(const std::set<int> & layers1,
const std::set<int> & layers2) {
// Check if any number is equal in the layers
for (int num : layers1) {
if (layers2.contains(num)) {
// Common layer found
return true;
break;
}
}
// No common layer found
return false;
}
CollisionSystem::CollisionInternalType
CollisionSystem::get_collider_type(const collider_variant & collider1,
const collider_variant & collider2) const {
if (std::holds_alternative<std::reference_wrapper<CircleCollider>>(collider1)) {
if (std::holds_alternative<std::reference_wrapper<CircleCollider>>(collider2)) {
return CollisionInternalType::CIRCLE_CIRCLE;
} else {
return CollisionInternalType::CIRCLE_BOX;
}
} else {
if (std::holds_alternative<std::reference_wrapper<CircleCollider>>(collider2)) {
return CollisionInternalType::BOX_CIRCLE;
} else {
return CollisionInternalType::BOX_BOX;
}
}
}
bool CollisionSystem::get_collision(const CollisionInternal & first_info,
const CollisionInternal & second_info,
CollisionInternalType type) const {
switch (type) {
case CollisionInternalType::BOX_BOX: {
const BoxCollider & box_collider1
= std::get<std::reference_wrapper<BoxCollider>>(first_info.collider);
const BoxCollider & box_collider2
= std::get<std::reference_wrapper<BoxCollider>>(second_info.collider);
return this->get_box_box_collision(box_collider1, box_collider2,
first_info.transform, second_info.transform,
second_info.rigidbody, second_info.rigidbody);
}
case CollisionInternalType::BOX_CIRCLE: {
const BoxCollider & box_collider
= std::get<std::reference_wrapper<BoxCollider>>(first_info.collider);
const CircleCollider & circle_collider
= std::get<std::reference_wrapper<CircleCollider>>(second_info.collider);
return this->get_box_circle_collision(
box_collider, circle_collider, first_info.transform, second_info.transform,
second_info.rigidbody, second_info.rigidbody);
}
case CollisionInternalType::CIRCLE_CIRCLE: {
const CircleCollider & circle_collider1
= std::get<std::reference_wrapper<CircleCollider>>(first_info.collider);
const CircleCollider & circle_collider2
= std::get<std::reference_wrapper<CircleCollider>>(second_info.collider);
return this->get_circle_circle_collision(
circle_collider1, circle_collider2, first_info.transform,
second_info.transform, second_info.rigidbody, second_info.rigidbody);
}
case CollisionInternalType::CIRCLE_BOX: {
const CircleCollider & circle_collider
= std::get<std::reference_wrapper<CircleCollider>>(first_info.collider);
const BoxCollider & box_collider
= std::get<std::reference_wrapper<BoxCollider>>(second_info.collider);
return this->get_box_circle_collision(
box_collider, circle_collider, first_info.transform, second_info.transform,
second_info.rigidbody, second_info.rigidbody);
}
}
return false;
}
bool CollisionSystem::get_box_box_collision(const BoxCollider & box1, const BoxCollider & box2,
const Transform & transform1,
const Transform & transform2,
const Rigidbody & rigidbody1,
const Rigidbody & rigidbody2) const {
// Get current positions of colliders
vec2 final_position1 = AbsoluutPosition::get_position(transform1,box1.offset);
vec2 final_position2 = AbsoluutPosition::get_position(transform2,box2.offset);
// Scale dimensions
vec2 scaled_box1 = box1.dimensions * transform1.scale;
vec2 scaled_box2 = box2.dimensions * transform2.scale;
// Calculate half-extents (half width and half height)
float half_width1 = scaled_box1.x / 2.0;
float half_height1 = scaled_box1.y / 2.0;
float half_width2 = scaled_box2.x / 2.0;
float half_height2 = scaled_box2.y / 2.0;
// Check if the boxes overlap along the X and Y axes
return (final_position1.x + half_width1 > final_position2.x - half_width2
&& final_position1.x - half_width1 < final_position2.x + half_width2
&& final_position1.y + half_height1 > final_position2.y - half_height2
&& final_position1.y - half_height1 < final_position2.y + half_height2);
}
bool CollisionSystem::get_box_circle_collision(const BoxCollider & box1,
const CircleCollider & circle2,
const Transform & transform1,
const Transform & transform2,
const Rigidbody & rigidbody1,
const Rigidbody & rigidbody2) const {
// Get current positions of colliders
vec2 final_position1 = AbsoluutPosition::get_position(transform1,box1.offset);
vec2 final_position2 = AbsoluutPosition::get_position(transform2,circle2.offset);
// Scale dimensions
vec2 scaled_box = box1.dimensions * transform1.scale;
float scaled_circle = circle2.radius * transform2.scale;
// Calculate box half-extents
float half_width = scaled_box.x / 2.0;
float half_height = scaled_box.y / 2.0;
// Find the closest point on the box to the circle's center
float closest_x = std::max(final_position1.x - half_width,
std::min(final_position2.x, final_position1.x + half_width));
float closest_y = std::max(final_position1.y - half_height,
std::min(final_position2.y, final_position1.y + half_height));
// Calculate the distance squared between the circle's center and the closest point on the box
float distance_x = final_position2.x - closest_x;
float distance_y = final_position2.y - closest_y;
float distance_squared = distance_x * distance_x + distance_y * distance_y;
// Compare distance squared with the square of the circle's radius
return distance_squared < scaled_circle * scaled_circle;
}
bool CollisionSystem::get_circle_circle_collision(const CircleCollider & circle1,
const CircleCollider & circle2,
const Transform & transform1,
const Transform & transform2,
const Rigidbody & rigidbody1,
const Rigidbody & rigidbody2) const {
// Get current positions of colliders
vec2 final_position1 = AbsoluutPosition::get_position(transform1,circle1.offset);
vec2 final_position2 = AbsoluutPosition::get_position(transform2,circle2.offset);
// Scale dimensions
float scaled_circle1 = circle1.radius * transform1.scale;
float scaled_circle2 = circle2.radius * transform2.scale;
float distance_x = final_position1.x - final_position2.x;
float distance_y = final_position1.y - final_position2.y;
float distance_squared = distance_x * distance_x + distance_y * distance_y;
// Calculate the sum of the radii
float radius_sum = scaled_circle1 + scaled_circle2;
// Check if the distance between the centers is less than or equal to the sum of the radii
return distance_squared < radius_sum * radius_sum;
}
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