Top Tips: How to create great fireworks

November is the month of Fireworks. The fifth of November, Guy Fawkes Night, sees the commemoration of a failed attempt at blowing up the houses of Parliament. In modern times, we use it to see the colourful pyrotechnics of gunpowder explode against backdrops of music and merriment.

So for this some tips on how to create the magic of colourful gunpowder, Develop went in search of digital fireworks. We didn’t have to drive far as the artists at Playground Games offered to share their knowledge. Following the release of Forza Horizon 3, the studio has spent a lot of time making sure their skybox is as real as possible. So much so that the team went to Australia with a 12K camera rig to make sure it was accurate and that it looked good. The game was the first release on Xbox One to benefit from the console’s new High Dynamic Range (HDR) features. So Playground needed to know their catherine wheels from their sparklers. Here’s what they said.

“If you’re working in a physically based system, as Horizon is, I would say a useful tip would be to check your emissive values on the firework effect. If it’s not high enough, you’ll end up with an uncanny valley type visual where something just doesn’t quite work and it might be difficult to spot straight away.

"If you’ve been savvy enough to set relative values for other emissive light sources in your environment a good way of checking the fireworks is to compare them against these. Generally they should at least be a few stops higher than most other regular sources in the scene. Those things are bright!”
Ben Penrose Art Director Playground Games

“In Forza Horizon 3, we render a dynamic cubemap every frame for the car reflections. This has the added bonus of ensuring every time the fireworks go off they reflect perfectly on the car bodywork.’

“We took great care in the pre-production phase of Forza Horizon 3 to capture a wide range of photographic reference to ensure we got these relationships correct, which also put us in good stead when working in HDR as the base values we already setup to work with the increased brightness range of the displays.’’
Jamie Wood Lead Lighting Artist Playground Games