Glint-Runtime/docs/en/README.md

Glint Runtime — Documentation

Backend for executing compiled bytecode (.glbc) of the Glint UI framework. Loads bytecode, interprets VDOM, applies CSS-like styles, executes Rhai scripts, and renders the result via Iced (native GPU-accelerated GUI).

Project Structure

• src/main.rs — entry point, CLI parsing
• src/lib.rs — public API of the crate
• src/app.rs — GlintApp: Iced application, update/view
• src/cli.rs — CLI commands compile/run
• src/renderer.rs — Iced widgets: Element → iced::Element conversion
• src/perf.rs — PerfScope: performance measurement by phases
• src/interpreter/mod.rs — Interpreter: bytecode loading, VDOM eval
• src/interpreter/types.rs — Element, VNode, FlatVDom, Value, InternedStr, Document
• src/interpreter/style.rs — StyleSheet, StyleRule, StyleIndex, StyleCache, ComputedStyle
• src/interpreter/reactive.rs — ReactiveTracker: dependency graph
• src/interpreter/rhei.rs — RheiContext: Rhai script integration
• src/interpreter/reader.rs — Reader: .glbc bytecode reading
• src/interpreter/opcodes.rs — OP_* bytecode constants

Related Repositories

• glt (compiler .gltm/.glts → .glbc)

Key Concepts

• Document — loaded .glbc file: Element tree, style sheet, variables
• Element — VDOM node: type_name, properties, children, computed_style, element_id, content_hash
• VDOM — virtual tree, result of bytecode interpretation
• StyleSheet — style sheet with indexed lookup and computed style cache
• ReactiveTracker — tracks element → variable dependencies, dirty_set
• RheiContext — compiles and executes Rhai scripts, caches AST
• ComputedStyle — result of applying CSS rules: ~40 fields (color, padding, font-size, etc.)

Optimization Phases

See ARCHITECTURE-IMPROVEMENT-PLAN.md.

Implemented: phases 3–8, 10, 9.1–9.2 (content_hash, stable Iced widget IDs).

Remaining:

Phase	Description	Estimated Speedup
0	Profiling (bench, flamegraph)	—
1	Typed Values in styles instead of HashMap<String, String>	2–3×
2	String interning for hot paths	1.5–2×
9.3	Iced widget cache by content_hash	1.5–2× (render)