Bot Blast

Game Overview

A top-down, isometric twin-stick shooter that I conceived and developed over a couple of weeks to showcase my proficiency in Rapid Game Design and prototype/modularity work within Unreal Engine and blueprints. The concept is straightforward: battle against infinite, randomly generated waves of enemies while navigating ever-changing platforms.

Role

Game Design, Technical Design

Year

2024

Software

Unreal Engine 5, Blueurpint

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I designed the weapon system to be as modular and designer friendly as possible making full use of data assets and the Unreal Engine 'parent' system. Before jumping in engine I know I wanted to make different types of weapons and for each weapon to be unique and have different stats from one another but I didnt want to be working efficiently with lots of random or uneccorserry code, Therefore panning before hand was key as I could find an effective way to make weapons and have them working quickly and designer Friendly.

To do this I made a Base parent weapon class that would house all the 'main' weapon data needed for that weapon to work with stats, FX, sounds and the mesh. This data would then be sent down to child classes that were more specific to the weapon, which would then house the firing mechanic (line trace or projectile) or finer details. This allowed me to separate code into different areas so would know what I need to edit for when any bugs show up.

To house main weapon data, I used Data Assets. These would hold all the main data needed for the weapon to work. They also allowed for quick and easy changeability from a designer point of view as I could go into the 'DA' to change damage, fx stats on the fly.

Below is a image of the Data Asset for the Machine gun which is used to hold main weapon data. Each weapon has one of these.

I designed bot blast to be a short, fun experience with a retro feel to it. I wanted to emulate going to a classic arcade machine and playing a twin stick, shooter but using modern game engines in an efficient and design friendly way. Throughout my years of Unreal Engine and blueprint/coding I wanted to make a solo project that makes use of action, ai, level generation and design friendly planning to make a really modular framework that I could show off as well as a fun game to quickly play.

The Game makes uses of project initiation, AI, Level generation, Weapons and Game juice/ feel to make an exciting, fun game that most PC's can run.

There are currently 2 types of AI for the game, each different and serves a unique purpose. The first is a 'grunt' styled AI with the goal of getting close to the player to deal damage and/or knock them off the platform. The second is a turret that is stationary that fires a projectile at the player, similar to a motor when the player gets ion range. The projectile deals an AOE explosion that can damage multiple enemy around it as well as knock them off the edge of the map.

What separates them both is the AI runs off a behavior tree whist the turret uses a State machine within itself. I wanted to try both systems out to see how they function and find any differences. From what I learned, they are both similar however, the state machine is simpler to get started with, all be it a little complex to grasp.

To spawn the AI, I used data assets that would house different waves of AI inside. This meant I could create as many diffetrn combonations of AI as I felt I needed to, going from an easy wave to a hard wave. All of the spawning was held within a AI/spawner manager that would get a random Data Assets wave and spawn it onto the current/new platform.

The code below shows the function of getting a Data asset wave and setting it as the new wave to spawn.

The platforms serve as the only walk able surface for the player in the game and so I wanted there to be a variety of different platforms to keep the visuals of the game different and ever changing . To do this I made sure each platform again is copied from a parent class that has a base mesh inside to replace. All the platforms are the same size on the X,Y but can be as tall as they like. The reason for them all being the same size is because they all have anchor points on there meshes in certain places that are used to spawn another platform either to the left, right, forward or back.

Using the above rules meant I could make any platform in blender, they just had to be of a strict size and that's it.

I then made a platform manger that job was to spawn a new platform every 'x' seconds and delete the old one. This manager would also send any data across to other managers of the newly spawned should they need it.

The code below shows the initial spawning of the platform from a the game state updating the current state of the game.

As the game is infinite , the process of spawning a platform is on a timer that keeps going until the game state is updated to 'Endgame'. I made an array of all the platforms in the game that are set to being a hard reference so that they are loaded in game memory at the start and are kept there for further use in the game. However, if needed I could swap them out to being a soft reference and loaded in to decrease memory usage.