Game Dev Highlights Summary

Every highlight bullet from the 10 pages in this section, gathered on one page and grouped by the page it came from.

Rust Game Development Architecture

• ECS separates data (components) from behavior (systems) instead of bundling both in objects
• The scheduler runs systems in parallel automatically when their data access does not conflict
• Rust's borrow checker enforces ECS access rules at compile time, not at runtime
• Archetypes store components contiguously for cache-friendly iteration
• Fixed and variable timesteps solve two different problems: stable physics and smooth rendering

Game Dev Basics

• Bevy ECS separates data (components) from behavior (systems)
• Schedules order systems for parallel execution where safe
• wgpu powers cross-platform rendering in Bevy and custom engines
• Fixed timestep keeps physics stable independent of FPS
• Asset server loads and hot-reloads textures and models

Bevy Engine

• ECS stores components in tables for cache-friendly iteration
• Systems are functions with Query/Res/Commands parameters
• Plugins bundle related systems and resources
• Schedules run sets in parallel when access does not conflict
• Reflect and scenes enable editor-adjacent workflows

Assets & Scenes

• AssetServer loads assets asynchronously by path handle
• Handles are cheap clones; data lives in Assets<T> resource
• Scenes spawn entity hierarchies from serialized files
• Asset hot-reload speeds iteration in dev builds
• Organize assets/ folder mirroring logical game domains

Input & Events

• InputAction map abstracts keyboard, mouse, and gamepad
• ButtonInput tracks pressed/just_pressed/just_released edges
• Events decouple combat, UI, and audio triggers
• Pointer picking uses camera raycast into world
• Focus and UI consume input before gameplay systems

Graphics with wgpu

• wgpu is WebGPU API on Vulkan, Metal, DX12, and WebGL
• Render pipelines bundle shader, layout, and vertex format
• Bevy uses wgpu internally via render graph abstraction
• WGSL shaders replace SPIR-V authoring for portability
• Compute shaders drive particles and GPU simulations

Physics & Audio

• Physics runs in FixedUpdate with stable timestep
• Rapier/Avian integrate as Bevy plugins with collider components
• Audio handles load like textures via AssetServer
• Spatial audio uses listener on camera entity
• Events trigger one-shot SFX without tight coupling

Game Loops & Timing

• Update runs once per rendered frame with variable delta
• FixedUpdate runs at constant Hz for physics integration
• Interpolation renders smooth motion between physics states
• Time<Fixed> resource exposes fixed_delta_seconds
• Spiral of death when fixed steps cannot catch up real time

Performance for Games

• ECS parallelizes systems when queries do not alias mutably
• Tracy/Puffin show CPU hotspots per Bevy system
• GPU bottlenecks need render doc or metal system trace
• Small components improve cache locality in hot loops
• Avoid heap allocations in Update systems every frame

Game Dev Best Practices

• Physics and deterministic sim live in FixedUpdate
• Small components and narrow queries keep ECS parallel
• Events for sparse signals; direct mutation for hot bulk paths
• Profile on target hardware, not only developer laptops
• Pin Bevy version; migrate with migration guides