Nailing down Warhammer 40,000: Boltgun's mix of modern and retro

According to developer Auroch Digital, the just-released Warhammer 40,000: Boltgun is "the game that should have been made in the '90s."

Boltgun is a first-person shooter set in the grim darkness of the tabletop strategy game's futuristic universe. It is also what many would call a "boomer shooter," a retro-tinged treatment of the genre that proudly wears its inspirations on its comically oversized epaulettes.

Speaking with GamesIndustry.biz, Boltgun lead designer Grant Stewart spells out those influences for people who couldn't discern them from the game's screenshots.

"We tried to pull the best bits out of the modern stuff while also staying true to the classic retro things"Grant Stewart

"With gameplay, obviously we were influenced by Doom and mods for that like Brutal Doom," Stewart says. "But we were also very heavily influenced from the more modern era of things harkening back to those shooters. I know I'm just mentioning various forms of Doom, but Doom 2016 and Doom Eternal were a big deal for us.

"We tried to pull the best bits out of the modern stuff while also staying true to the classic retro things."

It's not just Doom of course. From Quake to Unreal Tournament to other recent retro-inspired shooters like Ultrakill and Blood: Fresh Supply, there's a mix of modern and classic influences cited by the developers. They manifest most clearly in the game's visuals, which combine some Doom-esuqe chunky pixel art on the enemies and the player character's hands and weapons, while the environments are a higher-fidelity level of 3D graphics than you would have seen in the days when sprite-based enemies were state of the art.

Settling on the proper balance of old and new for the game's visuals was a lengthy process for the team, with a significant amount of back and forth to get the overall look to the point they were happy with it.

"Originally we channeled some really good references," lead artist Mark Chambers says. "There was one called Ion Fury, and then an Arcane Dimensions mod for Quake. We just picked that apart, the lighting, color schemes, all that good stuff.

"And then a really important pillar to capturing that retro aesthetic is pixel ratio sizing with our sprites, textures, environments and that kind of thing. I think bright color schemes also helped pull it back into that feeling of retro shooters."

Chambers says the team took advantage of many advances made in games tech since the days of Doom, from lighting and shader effects to texture work and particle effects.

"We just went to town on that," Chambers says of the particle effects. "There's not much retro stuff in the particles we use. We just splashed that over what was an old classic look and it made the particles in particular pop out and look quite modern, but it worked very well."

He notes the lighting in particular took a while to get right.

"With what Unreal is capable of with lighting, we had to pull it back quite a bit just to get more of a flatter, more classic lookMark Chambers

"With what Unreal is capable of with lighting, we had to pull it back quite a bit just to get more of a flatter, more classic look," he says. "There was a lot of experimentation. We had an ideal look in mind, and we had to pull back a bit on how much modern-looking stuff we used just to make sure it was in the right era."

Lead programmer Sam Chester adds, "We went back and forth on things like the normal maps and sprites, normal mapping sprites for the weapons and enemies. In pre-production we went back and forth on that sort of thing, but the compromise was that it places it so much better in the environment that we were like, yeah let's do it."

When Boltgun's developers weren't using modern development techniques to enhance older aesthetics with modern bells and whistles, they were using it to strip them away and replicate old results in a modern engine.

"In the original Doom, the way they did the darkness was this banded depth effect where it causes the environment to blend together because it steps the level of darkness as it moves up," Chester says. "So we worked on that and managed to get a shader that mimicked the effect, and at that point it was [clear] we really can marriage the two, having sprite-based enemies and more complex 3D environments."

Likewise, the gameplay is a mix of old and new.

"Everyone remembers classic retro shooters as being really, really fast, which they sort of were, but they're not as fast as you remember them being," Stewart says. "And you're not quite as mobile as you are in modern games. There are a lot of nice touches to things like movement that you get a sense of smoothness in slightly more modern games, and that comes with a degree of accessibility to new players that we wanted to have so that everyone could get into it and enjoy it."

"Everyone remembers classic retro shooters as being really, really fast, which they sort of were, but they're not as fast as you remember them being"Grant Stewart

While Boltgun puts forward a melange of first-person shooter eras, Stewart isn't overly concerned that will have the game struggling to appeal to people's nostalgia for one era or the other.

"There's definitely a degree of historical contraction that happens when you start lumping these things in together," he acknowledges. "The sprite-based enemies and more Quake-y style detailed 3D environments is something we debated internally, but we always really wanted the sprites because that's just what retro shooters are to us. And we also wanted really nice environments.

"So we were doing a lot of working out where the pixel density is and the complexity of the models, initially making much higher resolution, more detailed stuff and then slowly baking it down and making the textures more pixel-y and crunchy. It was an ongoing process."

With an "overwhelmingly positive" review average on Steam as of this writing, it seems the team's efforts to balance modern and retro had the desired effect. That said, the response from players – regardless of how much nostalgia they have for old first-person shooters – can't be entirely surprising to the team.

"I took the game to PAX East, and if I'm being honest, there was no difference in how anyone responded to it," Stewart says. "Everyone played it, immediately said how great it was and then jumped back into the queue to start playing again.

"Which feels slightly arrogant to say, to be honest, but that's genuinely what happened. We showed it to about 600 people and the response was universally, 'That's great, I really enjoyed it, when's it coming out?'"