We would like to say that The Witcher 3 has amazing looking foliage simply because it represents one of the deepest integrations of SpeedTree for games we’ve seen. However, the reality is that while SpeedTree is a really great resource, like any tool, how it is implemented in a game is more important than the tool itself. SpeedTree could be thought of as a really great hammer. It’s absolutely the right tool for the job and we recommend it to anyone looking to build a house but any carpenter who approaches a job with just a hammer and no blueprint or plan is bound to find the final product lacking. Art design as a blueprint is equally important to the tools used to build a game world.
We’re going to take a look at how the foliage in The Witcher 3 serves the greater purpose of the game through great design.
When you look out across a field there is an unevenness and a sense of wildness to the landscape. This is partially achieved by using a variety of plant height to create a sense of diversity and scale. If you were to take a look at a field, there are several layers of plant life that are all competing for the light. There is the short grass, the weeds, shrubbery and bushes, followed by the trees.
The landscape here subtly combines the different layers of assets to create a single landscape where the whole is more important that each individual piece. The colors are carefully chosen to blend together, not have each stand out on its own. Having these subtle layers does more for immersion than more accurately modeled assets. Often we get caught up on how well defined each model is when the more important factor is the gestalt effect of multiple layers creating a single scene.
This also serves to create a greater sense of scale. With enough smaller brush to compare to, the surrounding trees feel that much larger. Juvenile trees are contrasted against towering pines and oaks, heightening the sense of scale of the world and the depth of immersion.
A Redditor recently posted an image of The Witcher 3 with and without foliage. It’s amusing, but it actually highlights a very important point about the game. The game world is huge. At 136 square km it is easily 3 times larger than Far Cry 4 and 1.5 times larger than Skyrim. How does someone even begin to populate a world this huge without it feeling redundant?
Open world games can still be looked at in terms of the basic game mechanic of rooms and corridors. Rooms are areas where action or exploration is intended to take place and the corridor is a link between different rooms. When the majority of the action takes place in an open world, the foliage can function as a subconscious divider. The level of subtlety with which this is achieved is equal to the impact of immersion. A forest that you want to avoid is much more compelling than a forest that is clearly just blocking your way to another area. (I call this the “impenetrable hedgerow effect”) . For example, in the first town you encounter in the game there are distinctly separate locations. There is the town itself, the orchards on the edge of town, a bloody battlefield, a swamp. These are all distinct biomes that separate an open region into distinctly recognizable settings. So much so that they are easily used as landmarks for navigation.
The importance of these barriers is that it creates a very deep sense of location. For example, in the first region in the game there are distinctly separate locations. There is the town itself, the orchards on the outskirts, a bloody battlefield, a swamp. These are all distinct biomes that separate an open region into distinctly recognizable settings, in the same way that we recognize our real life surroundings by distinguishing and labeling different areas. This creates a virtual world with very real landmarks.
Jane Ng from Campos Santos made a great point in her GDC presentation on environmental design. Referring to a specific outcropping in the game she points out that you know you have an effective environment when it warrants a nickname. This kind of recognition means that after only a short time of playing in The Witcher 3 I can recall landmarks to create a mental map without referring to the in-game map. Although at that point I am subject to my very poor sense of direction.
Now I know that CDprojekt Red did use procedural tree placement to create the world, but they clearly did so in a very intentional way to create actual environments, not just a populated world.
Serving the Game Mechanic
Cohesion is one of the best indicators of good design. Creating subtly layered foliage and a sense of scale and well-defined areas serve the greater good of the game rather than just act as another pretty thing to look at. To take a look at this, let’s take a look at another title (which also used SpeedTree): Far Cry 4.
If I had to sum up Far Cry 4’s approach, I would probably label it as “Leave room for the elephants”. Far Cry 4 is, first and foremost, a masterpiece of an open world sandbox. It’s tightly focused on perfecting the lovingly crafted mechanics established in Far Cry 3, it knows what it’s trying to do and it absolutely refuses to apologize for it. It is a recipe for chaotic action and frantic chases. Less concerned with how individual areas differ, the primary concern is creating a world where no matter where you are, chaos could erupt. If the trees were more densely placed, fleeing enemy helicopters on an elephant might meet an anticlimactic end as you find yourself stuck in a thick woods. Now, the first sign that Far Cry 4 had great art design is that you never particularly notice or care that the trees are relatively evenly spaced, more so than what you might find in actual woods. Rather everywhere you look still looks jaw-droppingly fantastic.
Similarly, in The Witcher 3 the foliage, like every other part of the game, is always serving the game mechanic. If Far Cry 4 is a recipe for chaos, The Witcher 3 is a formula for immersion. While the world is open enough that you feel like you can simply explore and have memorable random encounters, the goal is to focus you on the cause and effects of events in this world, not just the outcome. The war-torn world that Geralt lives in is challenging and large. The woods are thick and limit your visibility and ability to fight. A nest of other worldly creatures lurks behind a small farm while drowners linger on the edge of the rivers and wetlands.
Pixel Peeping vs World Building
At SpeedTree, we’re fans of the small details that it takes to make a game. I’ve seen multiple SpeedTree employees huddled around a game trying to get a better look at branch seams, completely ignoring the zombies getting closer. But as much as we love the details, we are at our core gamers who just enjoy great games. It’s all too easy to get sidetracked trying to have the best possible technology powering your game while missing the big picture of what you are creating. Musicians do this all the time, nit picking over getting their sound just right, when in reality only 1% of the audience will ever notice the subtlety with which you were able to layer low gain overdrives. At the end of the show, what matters is the strength of the song, and the presence of the performance. Similarly, in games, at the end of the day you may have the best looking trees the world has ever seen but if it doesn’t serve the art design or the game mechanics, will anybody want to play it?
This is an editorial solely expressing the opinions of Danny Oakes. Please do not burn down our blog.