December 7, 2018

How the developer of GRIP used splines and the UE4 Marketplace to make a thrilling combat racer

Games

Learning

Caged Element

Blueprints

GRIP

Tech Blog

By Chris Mallinson

Hey, I’m Chris Mallinson, Game Director on the recently released GRIP - a high octane, hardcore combat racer for Steam, PlayStation 4, Xbox One and Nintendo Switch.

GRIP was built with Unreal Engine 4 and not only have the editor tools helped us a lot, but we also leveraged the Unreal Engine Marketplace to acquire assets that we could customize to our game’s needs.

One great way that the Unreal Engine Marketplace can benefit your project is by saving your team valuable time. If you’re creating an environment that needs a specific set of objects, they could potentially be found in bulk on the Marketplace. If you want to make them more unique, it’s as simple as modifying the textures and materials as you see fit – as long as you have the means to do so.

A prime example of this is some ice shards and formations we’ve got in a snow-blanketed racetrack that aren’t seen anywhere else in the game. The assets started out as rocks I purchased from the store before having one of GRIP’s artists modify the materials to cater them to our specific environment. We’ve done this for a few asset packs, and it certainly saves us from using unnecessary resources.

And it’s not just 3D assets we’ve taken advantage of - we’ve also purchased particle effects to use as a base for our more elaborate effects. For instance, the smoke material we use in all of our FX was part of a purchased asset that we repurposed many times over. We also did this to many other well-made particle materials. If we had to create these from scratch, it would involve learning new software and a lot of trial and error to get what we needed.

Outside of buying assets, we, of course, made a ton of our own. It’s incredible how many assets go into a full-featured game. The city levels in GRIP especially have a lot of different modular pieces to use, and one of the great tools in the Unreal Editor is splines, which makes up a lot of our environment since our levels are racetracks. We have a variety of road sections that can be easily created in length, twisting and criss-crossing over each other; using splines, it becomes just a matter of manipulating points and tangents.

The mesh used for most of the selected spline can be seen here:

We set up the spline Blueprint so that you can swap pieces in and out at any part, so in one section we would have the asset featured above, but in others there could be a higher wall, or a curved edge. The data array can be seen here:

It’s also great for creating roads embedded in terrain, as long as you’ve made the right mesh for it:

So, with the spline functionality already injected into Unreal Editor, we were able to jump quickly into creating racetracks.

The takeaway here is this - have fun with splines and don’t be afraid to grab assets from the Marketplace! It’s a matter of how you use them that makes them unique to your project, even if they are just being placed in a level with no modification – it’s still a creative process, and takes skill.

GRIP is now available on PC, PlayStation 4, Xbox One and Nintendo Switch. If you’re interested in checking it out, you can visit the game’s official website.

If you already own GRIP on Steam, you can head here to snag the custom Unreal Engine 4 vehicle skin pictured below for free!