praca_magisterska/games/unreal/tutorial/QUICKSTART-CODE-FIRST.md

Quick Start: Code-First Unreal Tutorial

Problem Solved: The Blueprint tutorial requires extensive manual UI work (60+ clicks to define 12 variables). The code-first approach lets you copy-paste entire code blocks instead.

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⚡ 3-Minute Quick Start

1. Choose Your Path

• New Project? → Start with Part 1 (C++): Project Setup
• Already have Blueprint project? → See Migration Guide below
• Just need code? → See existing implementations in Source/MCPGameProject/

2. Create C++ Project (New Projects Only)

If starting fresh:

Unreal Engine → New Project → Games → Blank
✅ Project Type: C++ (NOT Blueprint!)
Name: BulletHellGame

If you already have a Blueprint project, skip to Migration Guide below.

3. Copy-Paste the Classes

Instead of clicking through UI 60+ times, just copy these ready-to-use files:

STGPawn.h (Player) - Get from Appendix D

// All 12 player variables in one copy-paste:
UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Stats")
float MoveSpeed = 750.0f;

UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Stats")
FVector2D BoundsMin = FVector2D(-850.0f, -450.0f);

UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Stats")
FVector2D BoundsMax = FVector2D(850.0f, 450.0f);

// ... (9 more variables, all with defaults)

STGProjectile.h (Bullets) - Get from Appendix D

STGEnemy.h (Enemies) - Get from Appendix D

STGGameMode.h (Game Rules) - Get from Appendix D

4. Compile

• Click Compile in Unreal Editor (or build in IDE)
• Wait 30-60 seconds
• Done! All variables are now available in editor

5. Create Minimal Blueprints

Create Blueprint children only for visual assets:

1. BP_Player inherits from STGPawn → Assign ship mesh/material
2. BP_Bullet inherits from STGProjectile → Assign sphere mesh/color
3. BP_Enemy inherits from STGEnemy → Assign enemy mesh/material

No need to define variables! They all come from C++.

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📊 Time Savings

Task	Blueprint Approach	Code-First	Time Saved
Define player variables (×12)	15 minutes	2 minutes	⚡ 13 min
Define enemy variables (×15)	20 minutes	2 minutes	⚡ 18 min
Create enemy variants (×4)	35 minutes	8 minutes	⚡ 27 min
Implement firing logic	30 minutes	10 minutes	⚡ 20 min
Complete game	6-8 hours	2-3 hours	⚡ 4-5 hours

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🎯 Key Benefits

✅ Copy-Paste Variables

Blueprint:

Click + → Type "MoveSpeed" → Select type "Float" → Compile → Set value "750.0"
Click + → Type "BoundsMin" → Select type "Vector2D" → Compile → Set value...
... (repeat 10 more times, ~15 minutes total)

Code:

// Copy this entire block in 10 seconds:
UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Stats")
float MoveSpeed = 750.0f;

UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Stats")
FVector2D BoundsMin = FVector2D(-850.0f, -450.0f);

UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Stats")
FVector2D BoundsMax = FVector2D(850.0f, 450.0f);

✅ Version Control

Blueprint: Binary files, impossible to review changes

Binary files differ

Code: Readable diffs, easy code review

+ float MoveSpeed = 850.0f;  // Increased for better feel
- float MoveSpeed = 750.0f;

✅ Batch Modifications

Blueprint: Open each file, find variable, change value, save (2 min per file)

Code: Find/replace across all files (5 seconds)

Find: MaxHealth = 12;
Replace: MaxHealth = 24;
Replace All → Done!

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🔗 Full Documentation Links

1. Code-First Tutorial - Complete step-by-step guide
2. Appendix D: C++ Reference - Copy-paste ready code
3. Blueprint vs Code Comparison - Detailed time analysis
4. Main Tutorial Index - Access both approaches

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💡 Recommended Workflow

For This Bullet Hell Game:

1. ✅ Use C++ for ALL game logic and variables

   • Player stats, movement, firing
   • Enemy behavior, health, spawning
   • Game rules, timers, scoring

2. ✅ Use Blueprints ONLY for visual assets

   • Assign meshes and materials
   • Set particle effects
   • Configure sound effects

Result:

• 🚀 3x faster development (2-3 hours vs 6-8 hours)
• 📝 Maintainable code (version control, refactoring)
• 🎨 Easy visual tweaks (designers can change colors/meshes)

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🔄 Migrating from Blueprint to C++

Already started with the Blueprint tutorial? Here's how to move to C++ without losing your work.

Option 1: Add C++ to Existing Blueprint Project (Recommended)

This approach keeps your existing Blueprints and adds C++ support.

Step 1: Add C++ Support to Project

1. In Unreal Editor: Tools → New C++ Class

2. Choose any parent (e.g., "Actor") → Next

3. Name it anything (e.g., Dummy) → Create Class

4. This triggers C++ project generation!

   • Visual Studio/Rider opens
   • Source/ folder is created
   • Project compiles (~2-5 minutes first time)

5. After compilation, you'll have:

   YourProject/
   ├── Source/              ← NEW! C++ folder created
   ├── Content/             ← Your existing Blueprints (unchanged)
   └── YourProject.uproject
   

Step 2: Create C++ Classes

Now follow the C++ tutorial parts to create classes:

1. Tools → New C++ Class → Pawn → STGPawn
2. Copy-paste code from Part 2 (C++)
3. Compile
4. Repeat for bullets, enemies, etc.

Step 3: Reparent Existing Blueprints

Instead of creating new BP_Player, reparent your existing one:

1. Open your existing BP_Player Blueprint
2. File → Reparent Blueprint (top menu)
3. In the dialog, click "All Classes" dropdown
4. Search for STGPawn (your C++ class)
5. Select it → Reparent

What happens:

• ✅ BP_Player now inherits from STGPawn (C++)
• ✅ All C++ variables appear in Blueprint
• ✅ Your existing visual assets (meshes, materials) are preserved
• ✅ Old Blueprint variables become redundant (you can delete them)

Step 4: Clean Up Duplicate Variables

1. In BP_Player, look at "Variables" panel
2. You'll see duplicates:
   • MoveSpeed (from Blueprint - old)
   • MoveSpeed (from STGPawn - new, with C++ icon)
3. Delete the old Blueprint variables - keep only C++ ones
4. Compile and Save

Step 5: Migrate Logic (If Needed)

If you had Blueprint nodes for logic:

Option A: Keep Blueprint nodes for now (hybrid approach)

• Blueprints can call C++ functions
• Gradually move logic to C++ over time

Option B: Move everything to C++ immediately

• Copy Blueprint logic to C++ functions
• Delete Blueprint nodes
• Use Blueprints only for visual assets

Option 2: Fresh Start (Faster but Loses Visual Setup)

If you haven't done much visual work:

1. Create new C++ project
2. Follow C++ tutorial from Part 1
3. Manually recreate any visual assets from old project

When to use: If you're still early in the Blueprint tutorial (Parts 1-3).

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Migration Example: BP_Player → STGPawn

Before (Blueprint only):

BP_Player (Blueprint)
├── Components (added manually in editor)
│   ├── ShipMesh
│   ├── Camera
│   └── Hitbox
├── Variables (defined one-by-one in UI)
│   ├── MoveSpeed = 750.0
│   ├── BoundsMin = (-850, -450)
│   └── ... (10 more)
└── Event Graph (Blueprint nodes for logic)

After (Reparented to C++):

BP_Player (Blueprint, inherits from STGPawn C++)
├── Parent Class: STGPawn ← NEW!
├── Components (inherited from C++)
│   ├── ShipMesh (from STGPawn)
│   ├── Camera (from STGPawn)
│   └── Hitbox (from STGPawn)
├── Variables (inherited from C++)
│   ├── MoveSpeed = 750.0 (from STGPawn)
│   ├── BoundsMin = (-850, -450) (from STGPawn)
│   └── ... (all from C++)
└── Visual Assets Only (meshes, materials)
    └── ShipMesh → Assign cone mesh

Benefits:

• ✅ Variables now in version control (C++ files)
• ✅ Can modify via IDE (autocomplete, refactoring)
• ✅ Type-safe (compiler checks)
• ✅ Blueprint kept for visual assets only

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Common Migration Pitfalls

Problem: "I reparented but variables duplicated!"

• Solution: Delete the old Blueprint variables manually. Keep only C++ ones (they have a C++ icon next to them).

Problem: "Compilation errors after adding C++ support"

• Solution: Make sure Visual Studio has "Desktop Development with C++" workload installed. Check Output Log for specific errors.

Problem: "My Blueprint logic stopped working after reparenting"

• Solution: Check that function names match. C++ functions must be marked UFUNCTION(BlueprintCallable) to be called from Blueprints.

Problem: "Hot reload isn't working"

• Solution: Close Unreal Editor before compiling C++ changes. Reopen after compilation. Hot reload is unreliable.

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❓ FAQ

Q: I'm new to C++, should I use Blueprint instead?

A: The code-first tutorial is actually easier for beginners because:

• You copy-paste working code (less chance for errors)
• No complex node wiring (easier to understand flow)
• Clear error messages from compiler
• Better for learning (code is more transferable to other engines)

Q: Can I mix C++ and Blueprints?

A: Yes! That's the recommended approach:

• C++ base classes with all logic
• Blueprint children that inherit from C++
• Use Blueprints only for visual asset assignments

Q: What if I already started with Blueprints?

A: See the Migration Guide above! You can reparent existing Blueprints to C++ classes.

Q: Do I need to know Unreal's C++ API?

A: No! The tutorial provides complete, working code you can copy-paste. You'll learn the API as you read the code.

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🚀 Get Started Now

New Project: → Start with Part 1 (C++)

Existing Blueprint Project: → See Migration Guide

Build the complete bullet-hell game in 2-3 hours with copy-paste ready code!

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