[TECH DEMO] Voxel Placement and Inventory

NOTE: THIS WAS MADE IN 24 HOURS AS A TECHNICAL TASK FOR A GAME DEVELOPMENT JOB APPLICATION

UNITY VERSION

2022.3.4f1 (LTS)

CONTROLS

• WASD to move
• SHIFT to sprint
• SPACE to jump
• TAB to toggle inventory
• MOUSE to look around
• LEFT CLICK to place the current block
• RIGHT CLICK to remove the block you're looking at
• R to rotate the current block
• MOUSE SCROLLWHEEL to move the selected block closer or farther from you

The art is programmer art of course, but the inventory is simple to use, the block placing mechanic is extremely robust, and the character controller is nice and responsive.

Included are the following features:

• Block placing and removing, with rotation
• An inventory system and block selection
• Filter blocks by size in the inventory
• Support for filtering by arbitrary predicates
• Automatically generated 3D block icons in the inventory
• Support for custom icons in the inventory rather than the automatically generated ones
• Real-time renders of blocks upon hovering over them in the inventory
• A physics-based character controller with jumping and sprinting
• Special block shapes as described in the document
• Support for non-cubic blocks and blocks with arbitrary models, shapes, and shaders

How it works is that each block has a set of hand-placed connection surfaces that are used to determine if a block can be placed in a given location, and a set of blocking zones defining the volume of the block, which needs to be clear of other blocks in order to place it. This way of doing it is extremely flexible and allows practically any kind of block to be placed, no matter how weird its shape.

Raycasting and boxcasting makes little sense from both a gameplay and technical perspective given the weird shapes described in the document, so I opted for a more robust (if not slightly annoying) solution, which is that the player will simply place blocks N metres in front of them, where N is adjustable with the scroll wheel. This way you can place blocks easily no matter what awkward angle you're looking at them from, and you have total control over the exact position it'll be placed at.

The blocks are defined in JSON in the resources folder, and the block models and preview models are loaded from there too, as well as the icons and the tooltip render prefab. The green and red translucent block preview is done with a custom surface shader. (Evidently, I'm using the standard render pipeline).

As for the real-time block renders, that's accomplished with another camera rendering just the item, rendered to a RenderTexture, which is then displayed in the tooltip on hover. The pre-generated item icons are the same, only
rendered once at the beginning of the game and cached.

One thing to note is that performance-wise, this is definitely not scalable at the moment. If you wanted to expand this prototype to a full game, I'm afraid a dedicated voxel engine is the way to go if you want to allow the player to place hundreds or thousands of blocks while keeping performance and memory usage reasonable. Obviously, that's out of the question for just a prototype made in 48 (24, actually) hours, so I used this method instead.

Thanks for reading, and have fun with the prototype!