Struct TierLadder 

pub struct TierLadder {
    pub budgets: [TierBudget; 4],
    pub features: [TierFeatures; 4],
}

The canonical tier ladder: budgets, features, and safety constraints for every quality tier.

This is the single source of truth that the adaptive controller reads to decide degradation thresholds and feature availability.

Fields

budgets: [TierBudget; 4]

Budget for each tier, ordered Emergency → Fast → Balanced → Quality.

features: [TierFeatures; 4]

Feature toggles for each tier, same order.

Implementations

impl TierLadder

pub fn budget(&self, tier: LayoutTier) -> &TierBudget

Look up the budget for a specific tier.

pub fn features_for(&self, tier: LayoutTier) -> &TierFeatures

Look up the feature toggles for a specific tier.

pub fn default_60fps() -> Self

The default tier ladder calibrated from baseline profiles.

Frame budgets target 60fps (16,667µs) with progressive headroom allocation. Memory budgets are sized for typical terminal workloads (80x24 to 200x60). Queue budgets prevent unbounded accumulation of deferred work.

pub fn check_monotonicity(&self) -> Vec<String>

Verify that feature toggles are monotonically enabled up the ladder.

Returns a list of violations where a higher tier disables a feature that a lower tier enables.

pub fn check_budget_consistency(&self) -> Vec<String>

Verify that all budgets are consistent (sub-budgets sum to total).

pub fn check_budget_ordering(&self) -> Vec<String>

Verify that budgets increase monotonically up the tier ladder.

Trait Implementations

impl Clone for TierLadder

fn clone(&self) -> TierLadder

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for TierLadder

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

Formats the value using the given formatter.

impl Default for TierLadder

fn default() -> Self

Returns the “default value” for a type.

impl Display for TierLadder

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

Formats the value using the given formatter.