flare.johngerrard.net

[werner.poetzelberger]

 

John Gerrard
Flare (Oceania) 2021

Presented by The Hunterian / University of Glasgow.
In partnership with Art of Change 21. Supported by the Schneider Electric Foundation + The British Council.

John Gerrard’s Flare (Oceania) 2021 - a synthesis of climate and ocean issues. Gerrard responds to a statement from Tongan artist Uili Lousi, whose ancestral ocean is changing due to climate-heating emissions being created elsewhere in the world. Artwork is installed as a large-scale LED wall at the South Facade, University of Glasgow from 1pm - 7pm, 5th November and 10am - 8pm, 6th November 2021. Live feed runs from November 5th - November 15th at flare.johngerrard.net and available to embed globally.

 

 

[silent]

Nice one! Would it be possible to take a look how you simulate your fire particles (maybe some tech breakdown)? :)

[werner.poetzelberger]

We are utilizing the https://developer.nvidia.com/nvidia-flow to animate the fire, and render it in Unigine using a volume object.

Decided to go that way, as the movement of NVflow is sophisticated enough to create a fire/smoke like structure, as well it gives all the features to control the system.

Compared to a particlesystem it has a lot of advantages, but is also a beast which has to be handled. ;)

Not sure if I can give a real tech breakdown, but if you are interested in implementing NVFlow it into your Engine, it would enrich UNIGINE a lot. (if thats possible)...

Some editors already using it like Touchdesigner ..

Edited November 10, 2021 by werner.poetzelberger

[silent]

We just interested in how you manage to render this volumetric after simulation :)

Right now no plans to integrate nVidia flow into the Editor or Engine.

[helmut.bressler]

Hello Silent,

22 hours ago, silent said:

We just interested in how you manage to render this volumetric after simulation :)

 

Unfortunately NVFlow is not open source. But I spent quite a lot of time with the library, so I will try to answer that.

In contrast to our hand written fluid sim in http://www.johngerrard.net/western-flag-spindletop-texas-2017.html , NVFlow is using a sparse 3d texture for simulation -  the fluid domain is splitted into bricks. The simulation is not running on cells which are empty, which saves a lot of computational work. I guess the tricky part of such a design is, to figure out when a brick has to be allocated.

The sparse design is also quite usefull for rendering. Instead of rendering the fluid domain -  as we did in Western Flag -  only non-empty bricks are renderer.

The renderer runs first a couple of sorting steps for generating a brick list sorted with respect to the camera distance. I guess the vertex shader runs on a list of boxes which are moved to the position of the respective brick (its only a single draw call, i don't know if that has any impact on the render order of the bricks).

The library offers also the option to split up the rendering into several 2d texture 'slices' of different resolution - bricks which are further away from the camera can be rendererd with a lower resolution this way.

22 hours ago, silent said:

Right now no plans to integrate nVidia flow into the Editor or Engine.

Thats not supprising, given that the version on Github only supports DX11 and DX12.

But I must say that the API is a very nice abstraction for fluid simulation - could definitely serve as guidline for someone who wants to create a fluid simulation library.