🎮 Modular Auto-Battler Core

A tactical 2D core featuring tactical drawing mechanics and an autonomous combat system.
👉 Click here to play the WebGL build!

🗺️ So, how is it wired up?

The loop here is dead simple: you sketch a formation on the ground, hit "WAR!", and let the AI take the wheel. I was aiming for a totally hands-off experience—once your units hit the field, they’re on their own. They handle their own targeting and movement logic without any babysitting from the player.

🎬 Menus & Level Flow

Quick look at the UI and level selection.

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✏️ Positioning Units

The drawing-to-deployment mechanic in action.

🏗️ Architecture & Decisions

I'm not a fan of "spaghetti code," so I tried to keep this project as modular as possible using SOLID principles. It makes adding new units or mechanics way less of a headache:

• Event-Driven Chaos: I used a GameEvents bus so the UI and gameplay don't even need to know each other exist. They just trigger events, and whoever needs to listen, listens.
• Unit AI (FSM): Dealing with unit states can get messy fast. I stuck with a Finite State Machine so each unit always knows if it should be moving, attacking, or just standing there.
• Data-Driven (SO): All unit stats—health, damage, speed—are tucked away in ScriptableObjects. This means I can balance the game in the Inspector without waiting for the code to recompile every time.
• Optimization: Constant Instantiate and Destroy calls are a performance killer. I built a custom Object Pooling system to recycle units and projectiles, keeping the frame rate steady.

🎨 Game Feel & Visual Feedback

A core mechanic isn't complete without the right "juice." The visual systems are completely decoupled from the logic:

• Breathing & Locomotion: Units have idle breathing animations and walking sways (UnitBreathingVisuals).
• Dynamic Aiming: Ranged units track targets with their weapons, and melee units have dedicated swing animations.
• Damage Readability: A pooled DamageTextManager handles rising combat text so the player can always read the battle flow.

🛠️ A Bit More Technical (Expand)

1. ⚔️ Smart Targeting & Zero-Allocation Physics The FSM runs 4 main states. Target detection relies on zero-allocation physics (Physics2D.OverlapCircle techniques) to prevent GC spikes. To make combat look natural, I implemented a Hysteresis system (units won't switch targets unless the new target is significantly closer, e.g., 12%) and a Focus Timer (minimum 0.5s lock-on) to prevent jittery targeting.

2. 🎯 Battle Cleanup A tricky part was units dying while the game was still looping through the active list. To fix this, I added a _pendingRemovals queue to safely clean up dead units at the end of each frame, avoiding InvalidOperationException errors.

3. 🤖 Dynamic WaveDirector The AI doesn't just pick random enemies. It calculates a dynamic budget based on the base reward and weights your current army composition. If you spam ranged units, the AI dynamically assigns a +4 weight bias to anti-ranged counter units to give you a real challenge.

4. ✏️ Drawing UX (Backtracking) The line drawing system calculates path length limits dynamically (PathUtils.GetTotalLength). I also implemented path backtracking—if the player moves the cursor backward, the line safely undoes itself, creating a much smoother UX before deploying UnitSpawner.SpawnUnitsOnPath().

5. 📊 Level Economy The LevelManager rewards you for being efficient. If you win with unused units still in your hand, you get a gold bonus.

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🚀 Performance: The Pooling System

I’m pretty strict about not wasting CPU cycles. By using UnitFactory and ProjectileFactory, the game barely has to create anything new during a fight. Everything is recycled from the pool.

The Hierarchy stays clean because objects are reused instead of destroyed.

🛠️ Custom Editor Tools

I think a good project should be easy to balance for people who don't want to touch code. I built these two tools to speed things up:

⚙️ Level Generator	📦 Data Management
A quick tool to generate 100 levels. It uses templates like Grid or Wedge so I don't have to manually place every unit.	All unit stats are Inspector-ready. You can tweak attack speed or HP and see the changes live without a recompile.

🎬 Core Scene Flow

graph TD
    StartScene[Start Scene] --> ModeSelection{Pick Mode}
    ModeSelection -->|Campaign| CampaignScene[Load 100-Level Campaign]
    ModeSelection -->|AI Wave| AiWaveScene[Dynamic AI Drafting]
    
    CampaignScene --> Drawing[Player draws formation lines]
    AiWaveScene --> Drawing
    
    Drawing --> War["WAR!" starts the FSM simulation]
    War --> BattleEnd[Battle ends & Rewards calculated]

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