{
  "name": "CollisionBeginEvent",
  "main": {
    "name": "CollisionBeginEvent",
    "namespace": "sofa::simulation",
    "module": "Sofa.framework.Simulation.Core",
    "include": "sofa/simulation/CollisionBeginEvent.h",
    "doc": "Event fired by CollisionVisitor before performing the collision detection step.",
    "inherits": [
      "Event"
    ],
    "templates": [],
    "data_fields": [],
    "links": [],
    "methods": [
      {
        "name": "getEventTypeIndex",
        "return_type": "int",
        "params": [],
        "is_virtual": false,
        "is_pure_virtual": false,
        "is_static": false,
        "access": "public"
      },
      {
        "name": "checkEventType",
        "return_type": "bool",
        "params": [
          {
            "name": "event",
            "type": "const Event *"
          }
        ],
        "is_virtual": false,
        "is_pure_virtual": false,
        "is_static": true,
        "access": "public"
      },
      {
        "name": "GetClassName",
        "return_type": "const char *",
        "params": [],
        "is_virtual": false,
        "is_pure_virtual": false,
        "is_static": true,
        "access": "public"
      }
    ]
  },
  "desc": {
    "description": "The `CollisionBeginEvent` is part of the SOFA simulation module and serves as an event fired by the `CollisionVisitor` before initiating the collision detection step in simulations involving collision handling. This event inherits from the general `Event` class, providing a mechanism for signaling the start of collision processing within the simulation framework.\n\n**Role in the SOFA Ecosystem:**\nThis component plays a crucial role in the collision pipeline by notifying relevant components about the beginning of the collision detection phase. It facilitates coordination between different parts of the simulation that may need to react or prepare based on upcoming collision events.\n\n**Interactions with Other Components:*\nThe `CollisionBeginEvent` interacts primarily with the `CollisionVisitor`, which is responsible for managing and executing collision-related tasks throughout the simulation. Through its event mechanism, it integrates into SOFA's broader event-driven architecture, allowing other components to register listeners or callbacks that handle this specific event.\n\n**Practical Usage Guidance:**\nThe component provides methods like `getEventTypeIndex` and `checkEventType`, which can be used for identifying and verifying the type of event. Its primary use is internal to SOFA's collision detection mechanism; users typically do not interact with it directly but may utilize its presence when implementing custom collision behaviors or handling events in their simulations.\n\n**Data Fields:**\nThe component does not have explicit data fields, as its role is purely signaling the start of a specific phase within the simulation workflow."
  },
  "maths": {
    "maths": "The `CollisionBeginEvent` is an event class within the SOFA simulation framework, specifically designed to signal the start of collision detection during a simulation. This event inherits from the general `Event` class and does not contribute directly to any governing equations or operators in the finite element method (FEM) pipeline. It primarily serves as a signaling mechanism for coordinating different components involved in handling collisions.\n\n### Governing Equations / Operators:\n- **Mass Matrix M**: Not applicable.\n- **Stiffness Matrix K**: Not applicable.\n- **Internal Force $f_{int}$**: Not applicable.\n- **Residual R**: Not applicable.\n\n### Constitutive or Kinematic Laws Involved:\n- **Strain Measures, Stress Tensors, Hyperelastic Potentials, Damping Models, Constraint Jacobians**: None of these are directly involved in the `CollisionBeginEvent`. The event is purely a signaling mechanism and does not contain any mathematical or physical models.\n\n### Role in the Global FEM Pipeline:\n- **Assembly**: Not applicable.\n- **Time Integration**: Not applicable.\n- **Nonlinear Solve**: Not applicable.\n- **Linear Solve**: Not applicable.\n- **Constraint Handling**: The event indirectly supports constraint handling by signaling the start of collision detection, which can involve enforcing contact constraints.\n- **Mapping**: Not directly involved in any mapping process.\n\n### Numerical Methods or Discretization Choices:\n- None. This component does not encode any specific numerical methods or discretization choices; it is a purely event-based mechanism.\n\n### Fit into the Broader Variational / Lagrangian Mechanics Framework:\n- The `CollisionBeginEvent` fits into SOFA's broader event-driven architecture, which facilitates coordination among different simulation components. It serves as an important signaling mechanism for initiating collision detection phases within simulations involving contact and interaction between objects. However, it does not contribute to the variational or Lagrangian mechanics framework itself."
  },
  "summary": {
    "abstract": "`CollisionBeginEvent` signals the start of collision detection in SOFA simulations by notifying components through an event-driven mechanism.",
    "sheet": "# CollisionBeginEvent\n\n**Overview:**\n`CollisionBeginEvent` is part of the SOFA simulation module and serves as a signaling mechanism for initiating collision detection. It inherits from the general `Event` class, facilitating coordination among different parts of the simulation that need to react or prepare based on upcoming collision events.\n\n**Parameters and Data:**\nThe component does not have explicit data fields; its role is purely signaling the start of a specific phase within the simulation workflow.\n\n**Dependencies and Connections:**\nThe `CollisionBeginEvent` interacts primarily with the `CollisionVisitor`, which manages and executes collision-related tasks. It integrates into SOFA's broader event-driven architecture, allowing other components to register listeners or callbacks that handle this specific event.\n\n**Practical Notes:**\nThe component provides methods like `getEventTypeIndex` and `checkEventType` for identifying and verifying the type of event. Its primary use is internal to SOFA's collision detection mechanism; users typically do not interact with it directly but may utilize its presence when implementing custom collision behaviors or handling events in their simulations."
  }
}