Epic showed off an open world demo for Unreal Engine 4 at GDC that featured a clutch of beautifully realistic Hebredian artwork. They’ve now collected those assets together and released them as a free pack for developers.
Even more exciting than the freebies is how Epic made them.
The trees, logs, and boulders featured in the pack were all created using a technique called photogrammetry. Essentially, by taking a set of photos of a real world object, the Unreal Engine is able to create a realistic looking 3D object you can use to decorate your game worlds.
It’s a technique we saw used by The Astronauts in The Vanishing of the Ethan Carter, one of the best looking games of last year.
“For larger assets such as rocks, ground tiles, cliffs faces and tree trunks, reconstruction was performed directly from photographs using a process called photogrammetry” Epic explain. “These assets were then put through a proprietary ‘de-lighting’ process to make them suitable for use in any lighting scenario. Specular and roughness maps where then created to take full advantage of Unreal Engine 4’s Physically Based Rendering architecture. Finally game-optimized assets were generated with normal maps, LODs and collision meshes.”
While it’s a multi-stage process that not every studio is going to be able to employ in their pipeline, the results are spectacular.
The process isn’t suitable for every asset, however. When it came to making the smaller vegetation – such as flowers, bushes, and grass – Epic had to return to the more classic method of modelling the plants in a 3D editing software, simply using reference photos to create textures for the models.
You can add the asset pack to your build of the Unreal Engine 4 through Epic’s site.
Here’s Epic’s GDC session, showing off the open world demo and a more detailed breakdown of the photogrammetry process: