3D Asset Types

Describing the different asset types approach to help reduce drawcalls and filesize while increasing quality and performance.

Below are separate tabs that cover different approaches to Asset Creation. Each method has pros and cons, but generally comes down to Final Result VS Optimisation.

Modular Assets

Good for creating highly optimised models with small filesize that can create much larger assets and variations of them such as different buildings or ships to name a few. Think of it like 3D Lego.

Instanced Assets

General assets that have medium quality, but can be used many times in a space such as trees to generic furniture. Depending on the platform, it is possible to position, rotate and scale each asset to imply they are different, at little to no extra cost.

Centrepiece Assets

Important or Key assets that can be given more resources such as polycount and texture resolution. Due to their higher resources you can't have too many of these in a space.

Modular Assets are more like parts of assets that you combine into larger assets. A simple example is creating separate parts as walls, doors, windows, roof etc. so that you can make many different buildings with very few parts.

As each building is made with fewer assets the overall filesize is significantly smaller, meaning it takes less time to download or offers more room for other assets or textures.

If you manage to reduce the material count for the parts as well, you can have unique buildings with reduced drawcalls which allow for better experiences overall with a higher frame rate.

A great approach to getting the drawcalls down is using Palette Texturing or Trim Sheets. We have a tutorial on these if you want to go into more detail at Asset Creation Approaches.

Asset Creation

The first thing we need to do is create some Modular Assets. It's always good to look at reference of the style you are going for, but also other modular kits that are out there. These can be found online on YouTube tutorials, or things like the Unity store and Unreal Marketplace.

Jigsaw puzzle approach

Design all elements to be able to fit into each other perfectly. A simple approach to this is to have key dimensions for all parts, so the wall height is the same as the pillar height, and all doors are the same dimensions.

If possible, try to keep to the metre or at least to 0.25m as these are common snapping levels in most engines or 3D Creation programs.

Another tool that is useful is snapping to vertices. Unity has a great tool using the 'V' key to snap an assets vertex to another vertex, so make sure that all your vertices line up accordingly as well. If you hold 'Ctrl' while moving the asset will snap to the parameters set in the snap tools.

If you are putting two walls together make sure that the texture is tileable, so it doesn't look like there is a seam. Either that, or put a pillar or detail over the top to make it less obvious. This is easier if you are using a tileable texture for the walls, but if you are using a trim sheet approach you may need to be a little more accurate with placement of the UVs.

Pivot location

It is generally recommended to put the pivot of all parts at the end, or the center, of the asset so things line up easily. Walls should have the pivot on the ground, at the end of the wall. That way when you line them up it is easy to get the pillar where it needs to be or continuing the wall is also easy when using the snapping tools.

Adding the pivot to the end is recommended as it is easy to set the pivot to the centre of an object in Unity. This allows the asset to be pivoted from both the end or from the centre.

Overlapping assets

It may not be ideal for a wall to have a pillar at each end as when you copy the asset, there will be an overlap of two pillars. It is better to have one end of a wall have the pillar (and perhaps the pillar on its own to use as needed) or keep the wall and corners/pillars separate.

Creating the Assets

In the examples above a single texture for walls, wood, rock detail, metal and roof tiles was used in order to reduce filesize and drawcalls. High polygon assets were created before baking them into a single square to create the trim sheet texture. The modular assets were then created with this trim sheet. As noted, Trim sheets are covered in the Asset Creation Approachesdocumentation.

Building a full building with a few modular assets is quick and easy. That said, the above is a simple example but could be extended to something much more complicated and varied with more parts and variations.


In this tutorial we looked at the different types of assets and the pros and cons of each. With those approaches in mind, let's get into making the assets!

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