Enum rapier2d::dynamics::SpringModel

pub enum SpringModel {
    Disabled,
    VelocityBased,
    AccelerationBased,
    ForceBased,
}

The spring-like model used for constraints resolution.

Variants

Disabled

No equation is solved.

VelocityBased

The solved spring-like equation is: delta_velocity(t + dt) = stiffness / dt * (target_pos - pos(t)) + damping * (target_vel - vel(t))

Here the stiffness is the ratio of position error to be solved at each timestep (like a velocity-based ERP), and the damping is the ratio of velocity error to be solved at each timestep.

AccelerationBased

The solved spring-like equation is: acceleration(t + dt) = stiffness * (target_pos - pos(t)) + damping * (target_vel - vel(t))

ForceBased

The solved spring-like equation is: force(t + dt) = stiffness * (target_pos - pos(t + dt)) + damping * (target_vel - vel(t + dt))

Implementations

impl SpringModel

pub fn combine_coefficients(
    self,
    dt: Real,
    stiffness: Real,
    damping: Real
) -> (Real, Real, Real, bool)

Combines the coefficients used for solving the spring equation.

Returns the new coefficients (stiffness, damping, inv_lhs_scale, keep_inv_lhs) coefficients for the equivalent impulse-based equation. These new coefficients must be used in the following way:

• rhs = (stiffness * pos_err + damping * vel_err) / gamma.
• new_inv_lhs = gamma * if keep_inv_lhs { inv_lhs } else { 1.0 }. Note that the returned gamma will be zero if both stiffness and damping are zero.

Trait Implementations

impl Clone for SpringModel

fn clone(&self) -> SpringModel

Returns a copy of the value.

pub fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for SpringModel

impl Debug for SpringModel

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for SpringModel

fn default() -> Self

Returns the “default value” for a type.

impl Eq for SpringModel

impl PartialEq<SpringModel> for SpringModel

fn eq(&self, other: &SpringModel) -> bool

This method tests for self and other values to be equal, and is used by ==.

#[must_use]pub fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl StructuralEq for SpringModel

impl StructuralPartialEq for SpringModel