diff options
Diffstat (limited to 'src/crepe/system/CollisionSystem.h')
| -rw-r--r-- | src/crepe/system/CollisionSystem.h | 299 |
1 files changed, 299 insertions, 0 deletions
diff --git a/src/crepe/system/CollisionSystem.h b/src/crepe/system/CollisionSystem.h index c1a70d8..7e893c8 100644 --- a/src/crepe/system/CollisionSystem.h +++ b/src/crepe/system/CollisionSystem.h @@ -1,13 +1,312 @@ #pragma once +#include <optional> +#include <variant> +#include <vector> + +#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 "Collider.h" #include "System.h" namespace crepe { +//! A system responsible for detecting and handling collisions between colliders. class CollisionSystem : public System { public: using System::System; + +private: + //! A variant type that can hold either a BoxCollider or a CircleCollider. + using collider_variant = std::variant<std::reference_wrapper<BoxCollider>, + std::reference_wrapper<CircleCollider>>; + + //! Enum representing the types of collider pairs for collision detection. + enum class CollisionInternalType { + BOX_BOX, + CIRCLE_CIRCLE, + BOX_CIRCLE, + CIRCLE_BOX, + }; + + /** + * \brief A structure to store the collision data of a single collider. + * + * This structure all components and id that are for needed within this system when calculating or handeling collisions. + * The transform and rigidbody are mostly needed for location and rotation. + * In rigidbody additional info is written about what the body of the object is, + * and how it should respond on a collision. + */ + struct CollisionInternal { + game_object_id_t id = 0; + collider_variant collider; + Transform & transform; + Rigidbody & rigidbody; + }; + + //! Enum representing movement directions during collision resolution. + enum class Direction { + //! No movement required. + NONE, + //! Movement in the X direction. + X_DIRECTION, + //! Movement in the Y direction. + Y_DIRECTION, + //! Movement in both X and Y directions. + BOTH + }; + +public: + /** + * \brief Structure representing detailed collision information between two colliders. + * + * Includes information about the colliding objects and the resolution data for handling the collision. + */ + struct CollisionInfo { + Collider & this_collider; + Transform & this_transform; + Rigidbody & this_rigidbody; + Metadata & this_metadata; + Collider & other_collider; + Transform & other_transform; + Rigidbody & other_rigidbody; + Metadata & other_metadata; + //! The resolution vector for the collision. + vec2 resolution; + //! The direction of movement for resolving the collision. + Direction resolution_direction = Direction::NONE; + }; + +public: + //! Updates the collision system by checking for collisions between colliders and handling them. void update() override; + +private: + /** + * \brief Determines the type of collider pair from two colliders. + * + * Uses std::holds_alternative to identify the types of the provided colliders. + * + * \param collider1 First collider variant (BoxCollider or CircleCollider). + * \param collider2 Second collider variant (BoxCollider or CircleCollider). + * \return The combined type of the two colliders. + */ + CollisionInternalType get_collider_type(const collider_variant & collider1, + const collider_variant & collider2) const; + + /** + * \brief Calculates the current position of a collider. + * + * Combines the Collider offset, Transform position, and Rigidbody offset to compute the position of the collider. + * + * \param collider_offset The offset of the collider. + * \param transform The Transform of the associated game object. + * \param rigidbody The Rigidbody of the associated game object. + * \return The calculated position of the collider. + */ + vec2 get_current_position(const vec2 & collider_offset, const Transform & transform, + const Rigidbody & rigidbody) const; + +private: + /** + * \brief Handles collision resolution between two colliders. + * + * Processes collision data and adjusts objects to resolve collisions and/or calls the user oncollision script function. + * + * \param data1 Collision data for the first collider. + * \param data2 Collision data for the second collider. + */ + void collision_handler_request(CollisionInternal & data1, CollisionInternal & data2); + + /** + * \brief Resolves collision between two colliders and calculates the movement required. + * + * Determines the displacement and direction needed to separate colliders based on their types. + * + * \param data1 Collision data for the first collider. + * \param data2 Collision data for the second collider. + * \param type The type of collider pair. + * \return A pair containing the resolution vector and direction for the first collider. + */ + std::pair<vec2, Direction> collision_handler(CollisionInternal & data1, + CollisionInternal & data2, + CollisionInternalType type); + + /** + * \brief Calculates the resolution vector for two BoxColliders. + * + * Computes the displacement required to separate two overlapping BoxColliders. + * + * \param box_collider1 The first BoxCollider. + * \param box_collider2 The second BoxCollider. + * \param position1 The position of the first BoxCollider. + * \param position2 The position of the second BoxCollider. + * \return The resolution vector for the collision. + */ + vec2 get_box_box_resolution(const BoxCollider & box_collider1, + const BoxCollider & box_collider2, const vec2 & position1, + const vec2 & position2) const; + + /** + * \brief Calculates the resolution vector for two CircleCollider. + * + * Computes the displacement required to separate two overlapping CircleCollider. + * + * \param circle_collider1 The first CircleCollider. + * \param circle_collider2 The second CircleCollider. + * \param position1 The position of the first CircleCollider. + * \param position2 The position of the second CircleCollider. + * \return The resolution vector for the collision. + */ + vec2 get_circle_circle_resolution(const CircleCollider & circle_collider1, + const CircleCollider & circle_collider2, + const vec2 & final_position1, + const vec2 & final_position2) const; + + /** + * \brief Calculates the resolution vector for two CircleCollider. + * + * Computes the displacement required to separate two overlapping CircleCollider. + * + * \param circle_collider The first CircleCollider. + * \param box_collider The second CircleCollider. + * \param circle_position The position of the CircleCollider. + * \param box_position The position of the BoxCollider. + * \param inverse Inverted true if box circle collision, false if circle box collision (inverts the direction). + * \return The resolution vector for the collision. + */ + vec2 get_circle_box_resolution(const CircleCollider & circle_collider, + const BoxCollider & box_collider, + const vec2 & circle_position, + const vec2 & box_position) const; + + /** + * \brief Determines the appropriate collision handler for a collision. + * + * Decides the correct resolution process based on the dynamic or static nature of the colliders involved. + * + * \param info Collision information containing data about both colliders. + */ + void determine_collision_handler(CollisionInfo & info); + + /** + * \brief Handles collisions involving static objects. + * + * Resolves collisions by adjusting positions and modifying velocities if bounce is enabled. + * + * \param info Collision information containing data about both colliders. + */ + void static_collision_handler(CollisionInfo & info); + +private: + /** + * \brief Checks for collisions between colliders. + * + * Identifies collisions and generates pairs of colliding objects for further processing. + * + * \param colliders A collection of all active colliders. + * \return A list of collision pairs with their associated data. + */ + std::vector<std::pair<CollisionInternal, CollisionInternal>> + gather_collisions(std::vector<CollisionInternal> & colliders); + + /** + * \brief Checks if two collision layers have at least one common layer. + * + * This function checks if there is any overlapping layer between the two inputs. + * It compares each layer from the first input to see + * if it exists in the second input. If at least one common layer is found, + * the function returns true, indicating that the two colliders share a common + * collision layer. + * + * \param layers1 all collision layers for the first collider. + * \param layers2 all collision layers for the second collider. + * \return Returns true if there is at least one common layer, false otherwise. + */ + + bool have_common_layer(const std::set<int> & layers1, const std::set<int> & layers2); + + /** + * \brief Checks for collision between two colliders. + * + * Calls the appropriate collision detection function based on the collider types. + * + * \param first_info Collision data for the first collider. + * \param second_info Collision data for the second collider. + * \param type The type of collider pair. + * \return True if a collision is detected, otherwise false. + */ + bool get_collision(const CollisionInternal & first_info, + const CollisionInternal & second_info, + CollisionInternalType type) const; + + /** + * \brief Detects collisions between two BoxColliders. + * + * \param box1 The first BoxCollider. + * \param box2 The second BoxCollider. + * \param transform1 Transform of the first object. + * \param transform2 Transform of the second object. + * \param rigidbody1 Rigidbody of the first object. + * \param rigidbody2 Rigidbody of the second object. + * \return True if a collision is detected, otherwise false. + */ + bool get_box_box_collision(const BoxCollider & box1, const BoxCollider & box2, + const Transform & transform1, const Transform & transform2, + const Rigidbody & rigidbody1, + const Rigidbody & rigidbody2) const; + + /** + * \brief Check collision for box on circle collider + * + * \param box1 The BoxCollider + * \param circle2 The CircleCollider + * \param transform1 Transform of the first object. + * \param transform2 Transform of the second object. + * \param rigidbody1 Rigidbody of the first object. + * \param rigidbody2 Rigidbody of the second object. + * \return True if a collision is detected, otherwise false. + */ + bool get_box_circle_collision(const BoxCollider & box1, const CircleCollider & circle2, + const Transform & transform1, const Transform & transform2, + const Rigidbody & rigidbody1, + const Rigidbody & rigidbody2) const; + + /** + * \brief Check collision for circle on circle collider + * + * \param circle1 First CircleCollider + * \param circle2 Second CircleCollider + * \param transform1 Transform of the first object. + * \param transform2 Transform of the second object. + * \param rigidbody1 Rigidbody of the first object. + * \param rigidbody2 Rigidbody of the second object. + * \return True if a collision is detected, otherwise false. + * + * \return status of collision + */ + bool get_circle_circle_collision(const CircleCollider & circle1, + const CircleCollider & circle2, + const Transform & transform1, + const Transform & transform2, + const Rigidbody & rigidbody1, + const Rigidbody & rigidbody2) const; +}; + +/** + * \brief Event triggered during a collision between objects. + */ +class CollisionEvent : public Event { +public: + crepe::CollisionSystem::CollisionInfo info; + CollisionEvent(const crepe::CollisionSystem::CollisionInfo & collisionInfo) + : info(collisionInfo) {} }; } // namespace crepe |