Enum FailReason

pub enum FailReason {
    Inconsistent,
    DidntConverge,
    TooManyUnknowns,
}

Reasons that the constraint solver failed.

Examples

Most commonly, a failed solve will result from an over-constrained system. This can fall into two different categories: consistently over-constrained and inconsistently over-constrained.

A consistently over-constrained system is solveable, but has redundant constraints. In the example below, the distance between p1 and p2 is constrained to be 10 units twice.

Note that while the solver returns a failure, the locations for p1 and p2 have moved to satisfy the constraint.

use slvs::{
constraint::PtPtDistance,
entity::Point,
system::{FailReason, SolveResult},
System,
};

    let mut sys = System::new();
let g = sys.add_group();

let p1 = sys
    .sketch(Point::new_in_3d(g, [10.0, 10.0, 10.0]))
    .expect("p1 created");
let p2 = sys
    .sketch(Point::new_in_3d(g, [20.0, 20.0, 20.0]))
    .expect("p2 created");

// distance between p1 and p2 is 10
sys.constrain(PtPtDistance::new(g, p1, p2, 10.0, None))
    .expect("distance constraint added");
// distance between p1 and p2 is 10, a second time
sys.constrain(PtPtDistance::new(g, p1, p2, 10.0, None))
    .expect("distance constraint added");

let solve_result = sys.solve(&g);

if let SolveResult::Fail { reason, .. } = solve_result {
    assert_eq!(reason, FailReason::Inconsistent);
    println!("{:#?}", sys.entity_data(&p1));
    println!("{:#?}", sys.entity_data(&p2));
}

An *inconsistently over-constrained system has constraints that cannot be satisfied simultaneously. Here, we have tried to constrain the distances between p1 and p2 to be 10 units and 20 units apart, at the same time.

With inconsistently over-constrained systems, entities will remain in their initial position after the solve attempt.

use slvs::{
constraint::PtPtDistance,
entity::Point,
system::{FailReason, SolveResult},
System,
};

    let mut sys = System::new();
let g = sys.add_group();

let p1 = sys
    .sketch(Point::new_in_3d(g, [10.0, 10.0, 10.0]))
    .expect("p1 created");
let p2 = sys
    .sketch(Point::new_in_3d(g, [20.0, 20.0, 20.0]))
    .expect("p2 created");

// distance between p1 and p2 is 10
sys.constrain(PtPtDistance::new(g, p1, p2, 10.0, None))
    .expect("distance constraint added");
// distance between p1 and p2 is 20
sys.constrain(PtPtDistance::new(g, p1, p2, 20.0, None))
    .expect("distance constraint added");

let solve_result = sys.solve(&g);

if let SolveResult::Fail { reason, .. } = solve_result {
    assert_eq!(reason, FailReason::Inconsistent);
    println!("{:#?}", sys.entity_data(&p1));
    println!("{:#?}", sys.entity_data(&p2));
}

Variants

Inconsistent

DidntConverge

The conditions required to ensure that Newton’s method will converge were not met.

TooManyUnknowns

The system exceeds the hard-coded maximum of 2048 variables.

Trait Implementations

impl Clone for FailReason

fn clone(&self) -> FailReason

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for FailReason

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for FailReason

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl From<i32> for FailReason

fn from(value: i32) -> Self

Converts to this type from the input type.

impl Ord for FailReason

fn cmp(&self, other: &FailReason) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for FailReason

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

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for FailReason

fn partial_cmp(&self, other: &FailReason) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for FailReason

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Copy for FailReason

impl Eq for FailReason

impl StructuralPartialEq for FailReason