How to Create Large-Scale 3D Environments – Part I
Part I: Expanding the Toolset. Where to start and what to use
A beautiful 3D environment is, without a doubt, a keystone for a viewer’s suspension of disbelief. When clicking on a CG trailer, a sharp, bright, high-quality image is the first thing gamers pay attention to. In this article, Playsense’s Art Supervisor, Andrey Petrukovich, will describe the tools used by our team in the creation of 3D environments. In Part 1, we cover some of the software and the workflow stages that our agency utilizes when starting on a new 3D environment. In Part 2, we will see the tools in action when we create a mountainous landscape.
Inspiration: It All Begins with Instagram
How do you start your workday? Do you get an exact idea of what do you want to do right after accepting a task? In all fairness, not many of us can answer “yes” to that question. Most will look for some sources of inspiration or references that will help build an image in your head.
One of those sources may be Instagram. It can be used as a kind of an idea bank: a repository of pictures made by skilled photographers and travel bloggers that snap a giant number of shots on their journeys. You could bookmark these photos and browse through them when you haven’t got a clear understanding on how to proceed. In addition to that, Instagram has cool geo tags that can inform you of where the picture was taken. You can then use Google Earth tо jump to the location in the picture and do a flyover to look for more references and interesting details available in the region.
If your task is the recreation of a real terrain, you could use heightmaps — black and white images depicting the low and high points of a locale: the fields, the gullies, etc. Those maps are very easy to understand: the lighter the area, the higher the place. We’ve used a dedicated site, Terrain.Party, for such data (but for now, it has some problems with map saving that we hope will be resolved soon).
Then you need to import the heightmap into a terrain editor. At Playsense, we often use GAEA for this purpose. With the software, you can edit and alter the map, adding detail. It’s possible that you’ll need some additional overlays or textures to reach the state of a full-scale 3D model though.
You can import the created models of mountains or plains to Blender and use the software to make a rough draft of the landscape — it should already be possible to understand if the location turns out to be interesting and where the camera should be placed. Often, the entire concept gets reworked at this stage as the real scene could prove to be not as beautiful as you imagined.
You could then circle back to GAEA or World Machine to create additional model textures or overlays that could be used to do some object scattering, as well as mix materials back in Blender.
The next stage is background rendering. At Playsense, we often use Terragen: it’s a bit of a niche tool that not many creators are aware of. But it’s an interesting piece of software that can be used in the creation of entire HDR spherical views, global landscapes, clouds, or the rendering of whole planets.
The resulting elements are imported back to Blender to create the final image, for the rendering process and, should the need arise, for some composing and additional color correction and image sharpening in Photoshop.
So, roughly, that’s how we do it at Playsense. Now, let’s see how the image creation actually works.
Heightmaps: Generated and Pre-Made Maps
As we mentioned earlier, at Playsense we use Terrain.Party for the creation of heightmaps. This site shows a map of the Earth and you can choose any block of land on, after which the heightmap of the locale will be automatically downloaded to your PC. Not the entirety of the Earth is depicted at high resolution. The Americas — especially the United States — are represented in the best quality, but the images of Europe are also good enough to work as references. The map ratio is about 30 meters, and the landscape available for the capture may vary from 8 to 60 kilometers.
We import the resulting map into a terrain generator. We prefer World Machine, a stable, easy-to-learn piece of software that’s widely accepted in video game development. It’s often used to create maps and levels in gaming and World of Tanks is no exception. World Machine utilizes a node system that’s very helpful in terms of the visual understanding of what’s going on and which elements affects others. It’s quick and sports a minimalistic UI. Yes, it could use some new elements and more flexible rendering, and sometimes, the landscape can drastically change in quality during the rendering, which only becomes obvious after every node’s rendering is finished. But, on the other hand, World Machine has the option of rendering only the node that has been altered, so there’s no need to re-render every single nodes.
World Creator
One of the cutting-edge terrain generators that has been gaining traction thanks to its creative arts orientation, World Creator doesn’t use a node system, sports a professional interface and can offer practically real-time landscape generation. Through the active use of the GPU, it’s very quick in terms of both rendering and adding overlays. As opposed to World Machine, this tool could be used for the final rendering as you can add clouds and light sources.
Terragen
This is not a classic terrain generator. It can create not only a single mountain, but an entire planet with professional-grade lighting, clouds, trees, scattered rocks and other objects. It’s a full-blown 3D package software, but it doesn’t have modeling and you can’t test the camera angles in a created landscape. Terragen is an old hand on the market, so it’s very stable and fairly quick. It doesn’t have any cool UI features. This simplicity and the lack of extraneous elements culminate in a good performance: the files created are mere kilobytes in size, and the software itself doesn’t require much space on your hard drive. However, it should be noted that poor technical documentation creates some difficulties in mastering the software.
GAEA
A classic terrain generator. It was developed by the team that’d worked on World Machine plugins, so both tools are similar in design.
Its good qualities are a modern user interface, the node system, excellent filter generation and a huge set of existing filters that allow for the quick creation of a landscape, no matter if it’s snow-capped mountain peaks or sand dunes.
Some of the bad qualities are its unstable performance and a number of bugs.
In Part II of our article, we’ll take a look at the use of all of these tools in the making of a mountain landscape.