Tips and Techniques/Natural Phenomena/Fireworks
From VFXPedia
- Fireworks always leave smoke trails which last longer than any stars and sparks, so it's better to generate smoke as a separate layer with a longer duration. In this case, you'll be able to adjust smoke's color and opacity independently from luminescent features. As smoke catches the light from the environment, it can look rather different in various positions or at different time and it will be easier to simulate light on it if it's separated.
- To do so, make an instance of your main pEmitter, deinstance its size and color properties, make particles completely transparent and zero-sized. After that, apply a pSpawn which emits FastNoise-based sprites (see Tips on creating smoke effects for more details about smoke).
- Smoke trails are mainly lit not by surrounding street lights or natural light sources, but by fireworks themselves.
- To simulate the light on smoke you can blur the layer with the luminescent part of the firework and merge it over the smoke layer with the following Merge parameters: Alpha Gain = 0, Operator = Atop.
- Note that smoke from consequent launches accumulates in the air and every new firework reveals not only its own smoke, but also everything which is left from the previous ones.
- Smoke from any kind of rocket-propelled projectile comes out in the direction which is opposite to the projectile's flight direction. It's better to use negative Inherit Velocity values than the Velocity and Angle. Smoke will automatically change the direction according to the rocket's trajectory.
- Stars and sparks are relatively small and they reach bigger apparent size because of their high brightness. Even peripheral fading areas of these objects are so bright that they exceed the white point (brighter than 1).
- Use the particle Color values up to 50 and add some glow to make them look real.
- Sometimes stars start to flicker by the end as they fade. This can be simulated with the Color over Life gradient.
- Don't waste your time on creating your own fireworks, better order them from Gregory Chalenko who's studied the subject thoroughly (chalenko2000@mail.ru).
- See a video example of a ready-to-use small firework.
