rapier/src/dynamics/joint/rope_joint.rs

use crate::dynamics::joint::{GenericJoint, GenericJointBuilder, JointAxesMask};
use crate::dynamics::{JointAxis, MotorModel};
use crate::math::{Point, Real};

use super::JointMotor;

#[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
#[derive(Copy, Clone, Debug, PartialEq)]
#[repr(transparent)]
/// A rope joint, limits the maximum distance between two bodies
pub struct RopeJoint {
    /// The underlying joint data.
    pub data: GenericJoint,
}

impl RopeJoint {
    /// Creates a new rope joint limiting the max distance between two bodies.
    ///
    /// The `max_dist` must be strictly greater than 0.0.
    pub fn new(max_dist: Real) -> Self {
        let data = GenericJointBuilder::new(JointAxesMask::empty())
            .coupled_axes(JointAxesMask::LIN_AXES)
            .build();
        let mut result = Self { data };
        result.set_max_distance(max_dist);
        result
    }

    /// The underlying generic joint.
    pub fn data(&self) -> &GenericJoint {
        &self.data
    }

    /// Are contacts between the attached rigid-bodies enabled?
    pub fn contacts_enabled(&self) -> bool {
        self.data.contacts_enabled
    }

    /// Sets whether contacts between the attached rigid-bodies are enabled.
    pub fn set_contacts_enabled(&mut self, enabled: bool) -> &mut Self {
        self.data.set_contacts_enabled(enabled);
        self
    }

    /// The joint’s anchor, expressed in the local-space of the first rigid-body.
    #[must_use]
    pub fn local_anchor1(&self) -> Point<Real> {
        self.data.local_anchor1()
    }

    /// Sets the joint’s anchor, expressed in the local-space of the first rigid-body.
    pub fn set_local_anchor1(&mut self, anchor1: Point<Real>) -> &mut Self {
        self.data.set_local_anchor1(anchor1);
        self
    }

    /// The joint’s anchor, expressed in the local-space of the second rigid-body.
    #[must_use]
    pub fn local_anchor2(&self) -> Point<Real> {
        self.data.local_anchor2()
    }

    /// Sets the joint’s anchor, expressed in the local-space of the second rigid-body.
    pub fn set_local_anchor2(&mut self, anchor2: Point<Real>) -> &mut Self {
        self.data.set_local_anchor2(anchor2);
        self
    }

    /// The motor affecting the joint’s translational degree of freedom.
    #[must_use]
    pub fn motor(&self, axis: JointAxis) -> Option<&JointMotor> {
        self.data.motor(axis)
    }

    /// Set the spring-like model used by the motor to reach the desired target velocity and position.
    pub fn set_motor_model(&mut self, model: MotorModel) -> &mut Self {
        self.data.set_motor_model(JointAxis::X, model);
        self
    }

    /// Sets the target velocity this motor needs to reach.
    pub fn set_motor_velocity(&mut self, target_vel: Real, factor: Real) -> &mut Self {
        self.data
            .set_motor_velocity(JointAxis::X, target_vel, factor);
        self
    }

    /// Sets the target angle this motor needs to reach.
    pub fn set_motor_position(
        &mut self,
        target_pos: Real,
        stiffness: Real,
        damping: Real,
    ) -> &mut Self {
        self.data
            .set_motor_position(JointAxis::X, target_pos, stiffness, damping);
        self
    }

    /// Configure both the target angle and target velocity of the motor.
    pub fn set_motor(
        &mut self,
        target_pos: Real,
        target_vel: Real,
        stiffness: Real,
        damping: Real,
    ) -> &mut Self {
        self.data
            .set_motor(JointAxis::X, target_pos, target_vel, stiffness, damping);
        self
    }

    /// Sets the maximum force the motor can deliver.
    pub fn set_motor_max_force(&mut self, max_force: Real) -> &mut Self {
        self.data.set_motor_max_force(JointAxis::X, max_force);
        self
    }

    /// The maximum distance allowed between the attached objects.
    #[must_use]
    pub fn max_distance(&self) -> Option<Real> {
        self.data.limits(JointAxis::X).map(|l| l.max)
    }

    /// Sets the maximum allowed distance between the attached objects.
    ///
    /// The `max_dist` must be strictly greater than 0.0.
    pub fn set_max_distance(&mut self, max_dist: Real) -> &mut Self {
        self.data.set_limits(JointAxis::X, [0.0, max_dist]);
        self
    }
}

impl Into<GenericJoint> for RopeJoint {
    fn into(self) -> GenericJoint {
        self.data
    }
}

/// Create rope joints using the builder pattern.
///
/// A rope joint, limits the maximum distance between two bodies.
#[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
#[derive(Copy, Clone, Debug, PartialEq)]
pub struct RopeJointBuilder(pub RopeJoint);

impl RopeJointBuilder {
    /// Creates a new builder for rope joints.
    ///
    /// This axis is expressed in the local-space of both rigid-bodies.
    pub fn new(max_dist: Real) -> Self {
        Self(RopeJoint::new(max_dist))
    }

    /// Sets whether contacts between the attached rigid-bodies are enabled.
    #[must_use]
    pub fn contacts_enabled(mut self, enabled: bool) -> Self {
        self.0.set_contacts_enabled(enabled);
        self
    }

    /// Sets the joint’s anchor, expressed in the local-space of the first rigid-body.
    #[must_use]
    pub fn local_anchor1(mut self, anchor1: Point<Real>) -> Self {
        self.0.set_local_anchor1(anchor1);
        self
    }

    /// Sets the joint’s anchor, expressed in the local-space of the second rigid-body.
    #[must_use]
    pub fn local_anchor2(mut self, anchor2: Point<Real>) -> Self {
        self.0.set_local_anchor2(anchor2);
        self
    }

    /// Set the spring-like model used by the motor to reach the desired target velocity and position.
    #[must_use]
    pub fn motor_model(mut self, model: MotorModel) -> Self {
        self.0.set_motor_model(model);
        self
    }

    /// Sets the target velocity this motor needs to reach.
    #[must_use]
    pub fn motor_velocity(mut self, target_vel: Real, factor: Real) -> Self {
        self.0.set_motor_velocity(target_vel, factor);
        self
    }

    /// Sets the target angle this motor needs to reach.
    #[must_use]
    pub fn motor_position(mut self, target_pos: Real, stiffness: Real, damping: Real) -> Self {
        self.0.set_motor_position(target_pos, stiffness, damping);
        self
    }

    /// Configure both the target angle and target velocity of the motor.
    #[must_use]
    pub fn set_motor(
        mut self,
        target_pos: Real,
        target_vel: Real,
        stiffness: Real,
        damping: Real,
    ) -> Self {
        self.0.set_motor(target_pos, target_vel, stiffness, damping);
        self
    }

    /// Sets the maximum force the motor can deliver.
    #[must_use]
    pub fn motor_max_force(mut self, max_force: Real) -> Self {
        self.0.set_motor_max_force(max_force);
        self
    }

    /// Sets the maximum allowed distance between the attached bodies.
    ///
    /// The `max_dist` must be strictly greater than 0.0.
    #[must_use]
    pub fn max_distance(mut self, max_dist: Real) -> Self {
        self.0.set_max_distance(max_dist);
        self
    }

    /// Builds the rope joint.
    #[must_use]
    pub fn build(self) -> RopeJoint {
        self.0
    }
}

impl Into<GenericJoint> for RopeJointBuilder {
    fn into(self) -> GenericJoint {
        self.0.into()
    }
}