Available for Game Dev & Collaborations

Indie Game Developer & Unreal Engine Specialist

Hi, I'm Rudolf Čuljak. Self-taught indie game developer designing, building, and publishing games with Unreal Engine 4 & 5, Blender 3D, and custom gameplay & physics systems.

Explore Games WhatsApp Me Email
rculjak84@gmail.com
091-2753-651
Zagreb, Croatia
Rudolf Čuljak
Optimus Games Mascot

Rudolf Čuljak

Unreal Engine / 3D Game Developer

UE 5.4 Blender 3D Google Play
UE4 & UE5 Physics & AVS Mastery
Blueprints Complex Logic & AI
My Journey

Driven by passion, built through dedication

A look into how I taught myself game development from the ground up.

Self-Taught Indie Game Development

A few years ago, I decided to create a rally game for mobile devices with the goal of publishing it on Google Play as a free download. At that time, I had access to Unreal Engine 4.21, a tool I had never used before and had no prior background in game programming.

By following selected tutorials, documentation, and experimenting every single day in my spare time (often just 1 hour a day while raising 3 kids), I pushed forward. Since Unreal Engine alone was not enough, I expanded into Blender for 3D car models and terrain, Daz3D for characters, Audacity for sound engineering, and GIMP for texturing.

"Unreal Engine is a vast toolset with limitless potential — nobody knows it all. I am confident in my abilities, but also eager and motivated to continue learning and improving."
Google Play Developer Page APKPure Developer Page

Vehicle & Character Physics

Implemented custom physics with UE4 PhysX, UE5 Chaos, and AVS (Advanced Vehicle System) with realistic vehicle weight, suspension, and gamepad handling.

AI & Behavior Trees

Created dynamic enemy patrol routines, reactive combat responses, group fighting algorithms, and fleeing civilian AI systems.

3D Modeling & Splines

Crafted custom car meshes, track assets, altitude heightmaps, and road splines based on real topographic data from Medvednica mountain.

ALS Locomotion & Combat

Deep experience integrating Unreal ALS (Advanced Locomotion System) with fluid parkour, modular weapon mechanics, and ragdoll transitions.

Toolkit & Tech

Technical Expertise

Engines, software, and systems I use to build complete interactive games.

Unreal Engine (UE4 & UE5)

Blueprints Visual Scripting AVS (Advanced Vehicle System) ALS (Locomotion System) Behavior Trees (AI) Data Structures, Arrays & Enums Niagara VFX & Ballistics FX Save Game & State Management UMG Widget UI Blueprints

3D Modeling, Animation & Art

Blender 3D Modeling Vehicle & Prop Design Daz Studio 4 (Morphs & Rigging) Real-World Splines & Heightmaps GIMP & Texture Editing Skeletal Mesh Rigging

Platforms, Audio & Tooling

Google Play Services Leaderboards & Achievements Android Studio Audacity (Sound Design) Git & GitHub Version Control Bluetooth Gamepad Mapping
Showcase

Featured Games & Applications

Explore independent titles developed using Unreal Engine and custom gameplay physics.

This is Rally UE5 Game
Unreal Engine 5 • Racing Google Play

This is Rally

Successor to Rally Sljeme, rebuilt in Unreal Engine 5. Features advanced physics powered by AVS (Advanced Vehicle System) for realistic car tuning, Bluetooth gamepad support, and a complete Championship mode with dynamic AI competitors across multiple difficulty classes.

AVS Physics Tuning & Realistic Handling Multi-tier AI Championship Opponents Gamepad & SaveGame Progression
Google Play Store Page
UE 5 AVS System Arrays & Enums Google Play
Solo UE5.4 Action Game
Unreal Engine 5.4 • Action Collaborative

Solo (Working Title)

Action-adventure title built on Unreal ALS (Advanced Locomotion System) with seamless parkour, hand-to-hand combat, ragdoll transitions, modular weapon systems (fire rate, recoil, ammo data tables), and smart AI enemies driven by Behavior Trees that flank and respond dynamically.

ALS Fluid Parkour & Climbing Modular Weapons & Recoil Data Tables Dynamic AI Behavior Trees & Patrols
UE 5.4 ALS System Niagara VFX Ballistics FX
Rally Sljeme Game
Unreal Engine 4 • Racing Debut Project

Rally Sljeme

My very first game project, created in Unreal Engine 4.21–4.27. Accurately mapped real-world tracks from Medvednica mountain using altitude data and road splines, custom vehicle models modeled in Blender, UE4 Nvidia PhysX, and integrated Google Play Leaderboards.

Real Medvednica Mountain Terrain Blender 3D Car Models Google Play Leaderboards
UE 4.27 Nvidia PhysX Blender 3D Splines
Special Transport Driver Manual App
Android Studio / UE • Mobile Utility Utility Tool

Special Transport Driver Manual

Specialized mobile utility application created to support real-world heavy and special transport operations. Includes international country transport guidelines, tie-down force calculators, crane load positioning calculations, and security checklists.

Interactive Crane & Tie-Down Calculators Multi-Country Regulation Database Mobile Optimized UI
Android Studio Unreal Engine Mobile UI Math Calculators

Additional Indie Projects & Prototypes

Microbe Invasion

Microbe Invasion

Dynamic particle and wave survival mechanics.

View on APKPure
Impossible Escape Free

Impossible Escape Free

Puzzle and precision movement obstacle game.

View on APKPure
Snob Neighbors

Snob Neighbors

Stylized environment and interactive AI stealth mechanics.

View on APKPure
Loptas Jumps

Loptas Jumps

Physics-based arcade timing and jump mechanics.

View on APKPure
Under The Hood

Blueprint Visual Scripting & Architecture

A glimpse into the clean node architectures, game saves, and data structures powering my games.

Unreal Engine Blueprint Nodes
Click to Inspect High-Resolution Blueprint Nodes

Clean Node Organization & Comments

Structured Blueprint graphs with clear execution paths, color-coded functional groups, and modular sub-functions.

Data Structures, Enums & Arrays

Centralized weapon, vehicle, and AI configuration tables enabling rapid balancing and dynamic runtime lookups.

Robust SaveGame & Cross-Platform State

Persistent championship progression, custom vehicle configurations, and high scores stored reliably across sessions.

Get In Touch

Let's Connect & Build Games

Interested in collaboration, game development opportunities, or project discussions? Reach out directly!

WhatsApp (Fastest Reply)

+385 91 275 3651 / 091-2753-651

Email

rculjak84@gmail.com

Download Portfolio Presentation PDF

Official Presentation Document (17.5 MB)

Location

Zagreb, Croatia (Remote Ready)