Alex de Rosée, Leif Burrows, Matthias Van Camp and David Osternacher talked about the way they create visual and audio content for new Total War game.
Alex de Rosée, Leif Burrows, Matthias Van Camp and David Osternacher talked about the way they create visual and audio content for new Total War game.
Introduction
Hello! We’re the team behind Total War: ARENA. The core members of our team are veterans from Shogun 2, Empire, Rome 2 and beyond. We may have started on different projects, but we were brought together by a passion to create a great dedicated multiplayer Total War title. At Creative Assembly, we actually have quite a few teams working on various projects, the Warhammer 2 team, the ARENA team, the Three Kingdoms team etc. We all tend to gravitate towards where our strengths and interests are, and for our team, that is in history and multiplayer.
The engine
The Total War engine decouples the simulation update and render updates, the former running at a fixed rate and the latter running as fast as the host PC can run it; this facilitates smoother performance on high-end PCs while ensuring that the simulation depth is the same whether you are running on a fast or slow PC. The simulation uses efficient entity structuring and common code paths to perform physics, collisions, animation, and damage updates in good time, with some parallelization used; nevertheless, the simulation update is computationally expensive so it runs at a significantly smaller rate than the rendering. The rendering side uses a wide range of scalable and optional paths, as well as multi-core threading, to maximize the quality on higher-spec PCs; the entities (men, buildings, etc) share a lot of textures assets, which isn’t obvious to the naked eye, to push data more efficiently to the GPU.
For online play, unlike other Total War games, the number of entities in a battle is fixed from one battle to another, so we can’t rely on reducing the amount of simulation required; to cope with this, a number of measures were taken: the simulation engine has been tweaked to allow running at a reduced rate, the network architecture has been completely replaced to synchronize the simulations of all participants, substantial changes were made to the player camera (although this was done for gameplay reasons more than technical, the render performance can benefit from this too). In addition, many changes were made to the simulation and control code to adapt to the modified gameplay requirements of the game: units are more responsive and less “sticky”.
Map production
Maps are worked on by both the designer and the artists. A single map will swap hands several times as a new design iteration or art pass is done. As you might expect, a map initially starts out as a rough grey box layout representing the core gameplay, then several playtests and iterations will take place before we commit and begin the first art pass. Further playtests and design iterations will continue throughout its development. We also ensure that the Artists are shown the design brief for a new map early on so that they can begin to plan any additional assets that may be needed, as well as get a general idea of the theme ahead of time and voice any potential issues they may anticipate.
We have our own in-house terrain editor which we use to develop the maps, starting with a flat plane and editing the terrain height data using brushes, etc. Combined with obstacles and other features in the map, these elements dictate visibility and flow for units. A specific function within the editor also allows the definition of the ground types, such as forest or mud, for the purposes of letting the battle code know when a unit should be affected by the buffs or debuffs these provide to the unit traversing them.
Texturing
For ARENA specifically, we tend to exclusively use Substance Painter for our Character Art pipeline. For Environment Art, Substance Designer often gets used to creating tiling terrain textures, and to help in producing texture atlases.
Once the artist completes his/her work on this part of the process, we have an automated export script that then takes care of the rest of the process of getting textures into the game.
Since not all of our projects use the same shading model, we’ve put into place a “conversion” process that allows artists to create their textures in the industry-standard metalness/roughness model, without having to adjust to the shading model the engine uses.
First, the artist will author their textures in Substance Painter’s metalness/roughness model. The “conversion” step then takes these textures and converts them into the shading model the engine uses.
As artists tend to transfer internally between Total War projects, this makes getting started on a new project much easier, which helps tremendously with production. It also makes hiring and introducing new artists to our pipeline a lot easier.
Optimization
The prevention of crashing is mostly down to disciplined memory budgeting, strict procedures for submitting code and asset changes, and constant compatibility testing (both scripted automatic and human playing).
As stated above a number of techniques are used to simulate and render a very large number of entities. We are continually working on the game to improve graphical quality across all specs, for example investigating dynamic levels of detail for the terrain rendering.
Sound
When it comes to Total War games, the sheer complexity of them is probably the biggest challenge for sound. The player can choose to observe two single soldiers engaged in an epic sword fight, and on a moment’s notice move the camera out to see 10,000 men in battle, with war elephants stomping in the distance, and giant boulders being flung across the map by catapults. To make sure that any possible scenario captures the chaos and excitement of battle, but still maintain a clear and comprehensible sound mix, a wide range of complex systems is required.
Here’s a simple example: individual sword hits and battle screams are supplanted by carefully designed group fighting sounds, once the number of combatants exceeds a certain threshold. That way the player perceives the aforementioned chaos and excitement, without the sound actually being chaotic and thus unpredictably messy. All those group sounds are then crossfaded into distant-sounding versions of themselves as the camera moves away from the action. And if the camera moves even further away, all the distant sounds are merged into one big “distant battle ambient sound”, emanating from the direction of the action.
We have many systems like this in place, and with ARENA being a live service, we get to update and expand them regularly. As it happens, we have just released the first version of a dynamic mixing system, which allows us to improve the way we direct the focus of the mix to what we believe the player will want to (or should) focus on, at any given time. As with all of our work, we are perpetually trying to iterate on our previous designs and elevate the quality with each generation of experience gained. For the player to be able to hear exactly the things that are relevant to them, even though there are a million other things happening all around, requires us to bend the rules of in-game physics and realism in all kinds of fun ways.
To a layman’s ears, these can be fairly subtle things. But subconsciously they make a huge difference to the experience. Especially in a competitive game like ARENA, where giving concise feedback is an equally important goal for sound as delivering cinematic flair.
Another great way to succeed with both those directives is having an interactive music system. Every map in the game has its own set of tracks, which react dynamically to what’s happening in a battle. It starts with a map reveal and then goes into a tension state until the enemy is engaged and the music erupts into a full-on battle track. Depending on whether you’re witnessing arrow barrages, charges, brutal melee encounters or one of many other pre-defined situations, the tracks will transition seamlessly to suit the on-screen action.
The members of the audio team constantly work with game designers to identify these kinds of key situations in battles. By acknowledging them with a musical flourish, an ear-shattering UI sound effect or by having the Commander bark an order at the top of his/her lungs, we get to enhance the game through player feedback and engagement. And at the same time, our soundscape is enhanced by all the exciting stuff that’s going on in the battles!
Well, we’re currently in Open Beta! Which means that if you hit the minimum spec (which we’ve done our best to keep quite low) on a Windows PC, then you can create a Wargaming Account and start playing right now through the Wargaming Game Center. To find out more, visit https://totalwarARENA.net/ and join the battlefield.