class TextLayoutCache

Swift

final class TextLayoutCache

Keyed on (text, font, quantized width, mode). Yoga measure is chatty; this is the main Phase 4 perf lever.

Sources/LavaUI/Font.swift:1082

Properties

var hitRate: Double { get }

Fraction of lookups answered from the cache; 1 when there have been none.

Sources/LavaUI/Font.swift:1131

var hits: Int { get }

Lookups answered from the cache since the last resetStats().

Sources/LavaUI/Font.swift:1114

var misses: Int { get }

Lookups that had to measure since the last resetStats().

Sources/LavaUI/Font.swift:1116

static let shared: TextLayoutCache

The cache text layout goes through.

Sources/LavaUI/Font.swift:1084

Methods

func clear()

Drops every cached layout and zeroes the statistics.

Sources/LavaUI/Font.swift:1125

func layout(font: UIFont, text: String, availWidth: Float, mode: Int) -> Entry

Measures and wraps text, from the cache when this exact question was asked before.

mode is the Yoga measure mode: 0 undefined (one line per \n, availWidth ignored), 1 exactly and 2 at most (wrap to availWidth). Widths are compared at half-pixel precision.

Sources/LavaUI/Font.swift:1142

func resetStats()

Zeroes hits and misses.

Sources/LavaUI/Font.swift:1119

Types

TextLayoutCache.Entry struct

A measured text layout.

struct Key

What a cached layout is looked up by: the text, the font's identity, the available width and the Yoga measure mode.

Sources/LavaUI/Font.swift:1088