Enum DropReason

#[non_exhaustive]
pub enum DropReason {
    NotBlendable,
    ProviderLimitation,
    ConflictingValues,
    IncompatibleChannels,
}

Why a channel could not be carried through an operation.

Non-exhaustive: new operations find new reasons, and adding one must not break every caller that reports them.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

NotBlendable

The operation created vertices and the channel forbids derivation.

Not a failure: Blend::None is the channel stating that an invented value would be worse than an absent one.

ProviderLimitation

The provider does not carry attributes through this operation.

Distinct from Self::NotBlendable: the data could in principle have survived, but this implementation does not preserve it. Naming the provider’s limit separately keeps a capability gap from reading as a property of the data.

ConflictingValues

Vertices the operation merged carried different values.

A per-vertex channel holds one value per position, so a seam – two coincident vertices with different UVs, say – cannot survive a weld without keeping one side’s value for both. Dropping by name is the honest answer; a corner-indexed channel is the lossless one.

IncompatibleChannels

Inputs being combined define the same channel name with a different width or blend, so no single channel can hold them all.

Combining two "uv" channels, one 2-wide and one 3-wide, would have to invent a component or discard one; dropping by name is the honest answer.

Trait Implementations

impl Clone for DropReason

fn clone(&self) -> DropReason

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for DropReason

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

Formats the value using the given formatter.

impl Hash for DropReason

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for DropReason

fn eq(&self, other: &DropReason) -> 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 Copy for DropReason

impl Eq for DropReason

impl StructuralPartialEq for DropReason