Overview
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Course Setup and the Incremental Ladder
Why "Pixels to Worlds"
How to Use This Course
The Incremental Ladder (Step 0 to Step 7)
The Course Lenses
Diagram Legend and Notation Types

What Is a Game System?
Games as Simulations and State Machines
Input -> Simulation -> Rendering
Engine, Gameplay, Tools, Content

Time, Frames, and Game Loops
Real Time vs Game Time
Fixed, Variable, and Hybrid Timesteps
Frame Pacing and Budgets

Coordinate Systems and 2D/3D Math
Vectors, Matrices, Transforms
Spaces and Conversions
Spatial Reasoning as an Engineering Skill

Diagramming Game Architectures
Loop and Update-Order Diagrams
Scene Graphs and Entity Graphs
System Diagrams

Input, Update, Render: The Core Cycle
Input Models
Separating Input and Simulation
Rendering Sprites and Backgrounds

Time Steps and Determinism
Fixed Timestep Logic
Delta Time Pitfalls
When Determinism Matters

A Simple 2D Arcade Game
Minimal Architecture
Simple Collision and Responses
Extensibility Without Over-Engineering

2D Coordinate Systems, Layers, and Cameras
World vs Screen Coordinates
Parallax and Layered Worlds
Camera Movement

Tiles, Grids, and Platforms
Tile Maps as Data
Platformer Collision Resolution
Integrating Tiles with Entities

2D Collision Systems
Shapes and Overlap Tests
Broad Phase vs Narrow Phase
Triggers, Hitboxes, Hurtboxes

Scene and State Management
Scene Stacks and Transitions
Cutscenes and Scripted Sequences
Restarts and Checkpoints

UI, HUDs, and Layout Systems
UI Space vs World Space
Layout and Scaling
Input Routing

Saving, Loading, and Persistence
Serializing State and Progress
Checkpoints vs Snapshots
Save Data Versioning

3D Coordinate Systems and Transforms
3D Math Primitives
Model/View/Projection
Space Taxonomy

Cameras, Projections, and View Frustums
Perspective vs Orthographic
Camera Rigs
Visibility and Culling

Meshes, Materials, and Lighting
Mesh Data and Attributes
Materials and Shaders
Lighting and Shadows

3D Movement and Controls
Locomotion in 3D
Camera-Relative Controls
Uneven Terrain and Obstacles

Entity Models: OO vs ECS
Game Objects and Components
ECS Trade-offs
Messaging and Events

Physics Engines and Simulation
Rigid Bodies and Forces
Collision Shapes and Materials
Tuning for Fun

Animation Systems
2D Animation: Flipbooks, Transitions, and Layering Animation With Gameplay State
Skeletal Animation: Rigs, Skinning, and Pipeline Consistency
Blend Trees and IK Basics: Control Systems for Motion

AI Basics: Behavior and Decision Making
FSMs for Enemies: Predictable Behavior With Clear Debugging Boundaries
Behavior Trees and GOAP: Scaling Decision Logic and Handling Combinatoric Behaviors
Scripts, Data-Driven, and ML-Based Behavior: Choosing the Right Abstraction and Safety Limits

Navigation and Pathfinding
Grids vs Navmeshes: Modeling Walkable Space and the Cost of Authoring
A* and Variants: Heuristics, Performance, and Failure Cases
Dynamic Worlds: Obstacles, Crowds, Steering Behaviors, and Preventing Jittery Motion

Level Design and World Structure
World Structures: Linear, Hub, Open-World, Sandbox and How They Shape Systems
Pacing and Guidance: Difficulty Curves, Signposting, and Systemic Player Learning
Encounters and Set Pieces: Scripting Versus Systemic Composition and Reuse

Assets: Art, Audio, and Data
Art Asset Types: Sprites, Meshes, Textures, Shaders and How Constraints Propagate to Runtime
Audio Systems: SFX, Music, Mixing, and Reactive Audio as Gameplay Feedback
Data Schemas: Items, Quests, Enemies, Progression and Why Data Modeling Is a Design Act

Editors, Tools, and Workflows
Level Editors and In-Engine Tools: Authoring as Part of the Product, Not an Afterthought
Data-Driven Design vs Hardcoding: Iteration Speed and Risk Containment
Collaboration for Content: Version Control, Merges, and Workflows for Non-Programmers

Build Systems and Content Packaging
Import, Compression, Bundling: The Asset Pipeline as a Compiler for Content
Incremental Builds and Hot Reload: Iteration Time as a Strategic Advantage
Platform Packaging, Patches, DLC: Shipping and Updating Content Safely

Modding, Extensibility, and Scripting
Scripting for Game Logic: Why Scripting Boundaries Exist and How They Constrain Engine APIs
Modder-Facing APIs: Stability, Safety, and Enabling Creativity Without Breaking Saves
Sandboxing and Compatibility: Community Pipelines, Trust Boundaries, and Long-Term Maintenance

Multiplayer Models and Architectures
Game Modes: Co-op, Competitive, Persistent Worlds and Their System Consequences
Client-Server, Lockstep, Peer-to-Peer: Architecture Choices and the Failure/Cheat Surfaces They Create
Trust Boundaries: Authority, Validation, and Designing Against Cheating at a High Level

State, Lag, and Synchronization
Replication Basics: Snapshotting, Deltas, and Bandwidth as a Hard Budget
Prediction and Reconciliation: Making Latency Survivable Without Breaking Fairness
Tick Rates and Scalability: Balancing Responsiveness, Cost, and Correctness

Matchmaking, Sessions, and Persistence
Lobbies and Sessions: Lifecycle Management and Failure Handling
Progress and Inventory Persistence: Consistency, Rollback, and Player Trust
Cross-Play and Cross-Progression: Platform Constraints and Identity Boundaries

Online Services and Live Features
Leaderboards and Social Systems: Fairness, Abuse Surfaces, and Integrity
Telemetry and Experiments: Analytics and A/B Testing Without Compromising Gameplay
Live Events and Seasons: Content Rollout Pipelines and Operational Readiness

Security and Abuse Prevention
Anti-Cheat Strategies: Client Hardening, Server Authority, and Trade-offs
Rate Limiting and Moderation Tools: Abuse Detection, Enforcement, and Player Safety
Privacy and Compliance Basics: Data Minimization and Operational Constraints for Live Games

Game Engine Architecture
Core Subsystems: Rendering, Physics, Audio, Input, Scripting, UI, and How They Coordinate
The Main Loop with Many Systems: Update Ordering, Dependencies, and Debug Visibility
Plugins and Extensibility: Evolving Engines Without Rewriting the World

Cross-Platform Design and Performance Budgets
Platform Differences: PC, Console, Mobile, Web, and What They Imply for Architecture
CPU, GPU, and Memory Budgets: Planning for Bottlenecks Rather Than Reacting to Them
Input, Resolution, and Profiles: Device Variability and Maintaining Consistent Feel

Telemetry, Balancing, and Live Ops
Instrumentation for Decisions: Measuring What Players Experience, Not Just What Code Does
Balancing Systems: Rewards, Difficulty, Economies, and Designing for Change
Live Ops Operations: Deployments, Rollbacks, Incident Handling, and Sustaining Uptime

Production, Teams, and Pipelines
Roles and Interfaces: Engineering, Design, Art, Audio, QA, Production, and How Work Flows
Milestones and Deliverables: Prototypes, Vertical Slices, Alpha, Beta, Launch as Risk-Reduction Steps
Technical Debt and Roadmaps: Refactoring, Post-Launch Plans, and Sustaining Velocity

Ethically Designing Engagement and Monetization
Player-First Design: Avoiding Exploitative Patterns and Designing for Long-Term Trust
Monetization Models: Cosmetic Versus Gameplay-Affecting and the Systems They Force You to Build
Communities and Reputation: Moderation, Communication, and Why Ethics Is Operational Work

Game Loop and Simulation Patterns
Timesteps and Sampling: Fixed/Variable, Interpolation/Extrapolation, and Their Artifacts
Determinism Strategies: Deterministic Cores, Non-Deterministic Edges, and Debugging Benefits
Time Control Systems: Pausing, Time Scaling, Rewind, and the Architectural Prerequisites

Architectural Patterns in Games
Scene Graph vs ECS vs Data-Oriented: Choosing a World Model That Matches Scale and Tooling
Service Locator, Event Bus, DI: Dependency Patterns as Engine-Scale Coordination Tools
Scripting Boundaries and Engine APIs: Designing Stable Surfaces for Gameplay and Mods

UX, Feedback, and Game Feel
Responsiveness: Input Buffering, Latency Masking, and Perceived Control
"Juice" as System Design: Particles, Screen Shake, Sound, Haptics, and Budget-Aware Implementation
Accessibility and Options: Remapping, Difficulty, Visual/Audio Aids as First-Class Features

Performance, Profiling, and Optimization
CPU vs GPU Bottlenecks: Identifying the Limiter and Avoiding the Wrong Optimizations
Profiling and Hot Paths: Tools, Measurement Discipline, and Optimization Priorities
Content-Side Optimization: LODs, Draw Calls, Occlusion, and Why Content Is Often the Bottleneck

Reusable Patterns for Game Systems
Common Systems: Inventory, Quests, Dialogue, Progression, and Their Data Models
State Machines, Timelines, Events: Reusable Control Patterns Across Genres
Portability of Patterns: Reusing Systems Across Platforms and Genres Without Overfitting

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2D Collision Systems

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