path: root/src/dynamics/rigid_body_components.rs

use crate::dynamics::MassProperties;
use crate::geometry::{
    ColliderChanges, ColliderHandle, ColliderMassProps, ColliderParent, ColliderPosition,
    ColliderSet, ColliderShape,
};
use crate::math::{
    AngVector, AngularInertia, Isometry, Point, Real, Rotation, Translation, Vector,
};
use crate::parry::partitioning::IndexedData;
use crate::utils::{WAngularInertia, WCross, WDot};
use num::Zero;

/// The unique handle of a rigid body added to a `RigidBodySet`.
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, Default)]
#[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
#[repr(transparent)]
pub struct RigidBodyHandle(pub crate::data::arena::Index);

impl RigidBodyHandle {
    /// Converts this handle into its (index, generation) components.
    pub fn into_raw_parts(self) -> (u32, u32) {
        self.0.into_raw_parts()
    }

    /// Reconstructs an handle from its (index, generation) components.
    pub fn from_raw_parts(id: u32, generation: u32) -> Self {
        Self(crate::data::arena::Index::from_raw_parts(id, generation))
    }

    /// An always-invalid rigid-body handle.
    pub fn invalid() -> Self {
        Self(crate::data::arena::Index::from_raw_parts(
            crate::INVALID_U32,
            crate::INVALID_U32,
        ))
    }
}

impl IndexedData for RigidBodyHandle {
    fn default() -> Self {
        Self(IndexedData::default())
    }

    fn index(&self) -> usize {
        self.0.index()
    }
}

/// The type of a body, governing the way it is affected by external forces.
#[deprecated(note = "renamed as RigidBodyType")]
pub type BodyStatus = RigidBodyType;

#[derive(Copy, Clone, Debug, PartialEq, Eq)]
#[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
/// The status of a body, governing the way it is affected by external forces.
pub enum RigidBodyType {
    /// A `RigidBodyType::Dynamic` body can be affected by all external forces.
    Dynamic = 0,
    /// A `RigidBodyType::Fixed` body cannot be affected by external forces.
    Fixed = 1,
    /// A `RigidBodyType::KinematicPositionBased` body cannot be affected by any external forces but can be controlled
    /// by the user at the position level while keeping realistic one-way interaction with dynamic bodies.
    ///
    /// One-way interaction means that a kinematic body can push a dynamic body, but a kinematic body
    /// cannot be pushed by anything. In other words, the trajectory of a kinematic body can only be
    /// modified by the user and is independent from any contact or joint it is involved in.
    KinematicPositionBased = 2,
    /// A `RigidBodyType::KinematicVelocityBased` body cannot be affected by any external forces but can be controlled
    /// by the user at the velocity level while keeping realistic one-way interaction with dynamic bodies.
    ///
    /// One-way interaction means that a kinematic body can push a dynamic body, but a kinematic body
    /// cannot be pushed by anything. In other words, the trajectory of a kinematic body can only be
    /// modified by the user and is independent from any contact or joint it is involved in.
    KinematicVelocityBased = 3,
    // Semikinematic, // A kinematic that performs automatic CCD with the fixed environment to avoid traversing it?
    // Disabled,
}

impl RigidBodyType {
    /// Is this rigid-body fixed (i.e. cannot move)?
    pub fn is_fixed(self) -> bool {
        self == RigidBodyType::Fixed
    }

    /// Is this rigid-body dynamic (i.e. can move and be affected by forces)?
    pub fn is_dynamic(self) -> bool {
        self == RigidBodyType::Dynamic
    }

    /// Is this rigid-body kinematic (i.e. can move but is unaffected by forces)?
    pub fn is_kinematic(self) -> bool {
        self == RigidBodyType::KinematicPositionBased
            || self == RigidBodyType::KinematicVelocityBased
    }
}

bitflags::bitflags! {
    #[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
    /// Flags describing how the rigid-body has been modified by the user.
    pub struct RigidBodyChanges: u32 {
        /// Flag indicating that any component of this rigid-body has been modified.
        const MODIFIED    = 1 << 0;
        /// Flag indicating that the `RigidBodyPosition` component of this rigid-body has been modified.
        const POSITION    = 1 << 1;
        /// Flag indicating that the `RigidBodyActivation` component of this rigid-body has been modified.
        const SLEEP       = 1 << 2;
        /// Flag indicating that the `RigidBodyColliders` component of this rigid-body has been modified.
        const COLLIDERS   = 1 << 3;
        /// Flag indicating that the `RigidBodyType` component of this rigid-body has been modified.
        const TYPE        = 1 << 4;
        /// Flag indicating that the `RigidBodyDominance` component of this rigid-body has been modified.
        const DOMINANCE   = 1 << 5;
        /// Flag indicating that the local mass-properties of this rigid-body must be recomputed.
        const LOCAL_MASS_PROPERTIES = 1 << 6;
    }
}

impl Default for RigidBodyChanges {
    fn default() -> Self {
        RigidBodyChanges::empty()
    }
}

#[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
#[derive(Clone, Debug, Copy, PartialEq)]
/// The position of this rigid-body.
pub struct RigidBodyPosition {
    /// The world-space position of the rigid-body.
    pub position: Isometry<Real>,
    /// The next position of the rigid-body.