Firefighting really isn’t the central focus of enough games, is it? Side-scrolling roguelite Firegirl aims to right that historical wrong, and while the goal isn’t to simulate the real deal, its blazing buildings filled with vulnerable civilians are as close to that experience as you’d ever want to get.
Saving these trapped civilians isn’t just a case of extinguishing fires as fast as possible. Julien Ribassin, Firegirl’s VFX artist, programmer, and game designer, says exploration is the key to extracting each level’s survivors safely. “The goal of the game is actually not to extinguish all the flames, but to rescue the survivors trapped in the fire,” Ribassin explains. “Traversing the levels is no stroll though. Not only are there fire monsters and hazards in every corner, but you also have a limited amount of time to rescue the survivors before the fire engulfs the level. We want the player to be constantly torn between being thorough when exploring the level, and dashing around to get to the survivors as fast as possible.”
As the titular Firegirl, you explore each level by running and around and hopping across gaps, but you are also able to use the fire hose for some extra help getting around and saving lives. “What’s unique about Firegirl is the main weapon: the fire hose. Its main function is to shoot water in order to extinguish the flames,” Ribassin says, “but the hose is also how Firegirl navigates through each level, shooting the hose while jumping boosts her up.
“As the player upgrades the hose in between missions and learns to master the hose jump, Firegirl is eventually able to fly through the levels as if using some sort of deadly firefighting jetpack.”
While recent platformers and roguelikes like Celeste and Hades have pushed the boundaries for storytelling in their respective genres, Ribassin pitches Firegirl as more of an homage to ’90s Japanese arcade games, and as such, narrative isn’t really the main focus. “We have tried to create some quirky and endearing characters, and a story that players might be surprised by – hopefully players will find that there’s more going on in Firegirl than meets the eye,” Ribassin says.
The decision to use Unreal Engine 4 for Firegirl came about largely because of the game’s walking fire monsters. “It seemed essential to have reliable real-time lighting and shadow casting solutions as each enemy in the game would be a light source that can move and potentially be turned off,” Ribassin explains. “We had previous experience with Unreal so we felt that we could create something special using Unreal’s lighting tech mixed with some retro assets.”
Another key reason for choosing Unreal Engine 4 was Firegirl’s distinctive blend of 2D and 3D. While you can only move up, down, left, and right, the levels in Firegirl are designed like 3D dioramas, and as such you can pitch and lean with the camera to better assess the route ahead. “Unreal Engine 4 is famous for its real-time 3D graphics capabilities,” Ribassin says. “We then realized that it also has very solid 2D tools and that it’s surprisingly easy to blend those very different techniques together, like having a physically-based rendering material applied to an animated sprite.”
Firegirl started life as a traditional 2D side-scroller, but as art direction evolved Ribassin and Gabriel Miller – Dejima games’ other half – kept adding depth to the environments, gradually stripping out sprites for 3D meshes. Eventually, this led to more effort on materials, post-processing, and particle effects. “I think Unreal’s material tools are extremely powerful,” Ribassin says. “I cannot count the number of times we achieved the effect we were looking for by just playing around with the materials a bit. The tools for particle effects are also fantastic, and we used them often to make the 2D and 3D elements blend well.”
One thing that Firegirl does differently from other roguelites and platformers is how it uses procedural generation. Most games create a map and then spawn the player in at the start. However, Firegirl actually generates the level in real time as you play through it. “This allows us to take into account the player’s actions, tweak the level design, and adjust the difficulty in real time,” Ribassin explains.
There is a tradeoff, which is that generating the level live makes Firegirl much more CPU intensive than its retro aesthetic would suggest. For a team of two, working remotely with Ribassin in France and Miller in South Korea, solving issues like this is no mean feat. Fortunately, “Unreal Engine’s CPU profiling tools were a real godsend for this” says Ribassin.
In this sponsored series, we’re looking at how game developers are taking advantage of Unreal Engine 4 to create a new generation of PC games. With thanks to Epic Games and Dejima games.