flame-core_skill

Overview

This skill documents Flame Engine core fundamentals for building 2D games in Flutter. It covers the component system, input handling, collision detection, camera setup, animation, and scene management. The material helps developers structure game logic, render sprites, and manage interactions and UI overlays.

How this skill works

The skill explains how Flame organizes game objects as Components and PositionComponents, and how lifecycle methods drive load, update, and render. It describes input layers (touch, keyboard, gamepad), Hitbox-based collision detection with HasCollisionDetection, and camera features like viewfinder anchoring and follow behavior. It also details sprite animation types, animation groups, scene routing via RouterComponent, and overlay UI management.

When to use it

• Starting a new Flame game project and choosing component types
• Implementing player controls, touch or keyboard input, or gamepad support
• Adding collision detection and hitboxes for physics or interactions
• Setting up camera behavior, HUDs, and viewports
• Creating sprite animations, effects, or animation state groups
• Organizing scenes, menus, and overlays with RouterComponent

Best practices

• Prefer small, focused Components to keep lifecycle and updates simple
• Use PositionComponent subclasses for renderable objects and separate logic-only Components
• Define clear Hitbox shapes and layers to limit collision checks for performance
• Keep camera logic separate from gameplay logic; use the viewfinder to control anchoring and follow targets
• Use SpriteAnimationGroupComponent for state-driven animations to simplify state transitions
• Profile performance early and batch static graphics where possible

Example use cases

• Player entity built from PositionComponent with SpriteAnimationComponent and Hitbox for collisions
• Top-down camera following player with a fixed HUD overlay using Camera.viewfinder and overlays
• Menu and scene flow managed by RouterComponent with separate Components for each screen
• Touch and keyboard input handlers added to game for cross-platform controls
• Particle explosion effect triggered on collision using the Particles system