BMW Hydrogen 7 with case study ( How they made this ad)

Case Studies

BMW Hydrogen 7 (Pictorion das Werk)
Hydrogen liquid keeps the motor of the new BMW Hydrogen 7 model running, and so the launch-spot for the luxury car centers on water. And where there's water, there’s RealFlow. German digital image studio Pictorion das Werk took on the spot’s postproduction and created some hyper-real water simulations.
“Clean Energy” was the message that the Pictorion das Werk team wanted to pass on through the new BMW ad. To be more precise, the task was to visualize the unlimited strength of natural energy sources and their indefinitely useful application and utilization in our society to improve our environment.

Starting off with a trip to Iceland, director Jürgen Bollmeyer from German audiovisual communication firm Gate 11 took his team to the Skogafoss waterfall to shoot some reference material and study light set-ups. This reference material was to be combined later with 3D elements.

See the whole sequence of images here Several weeks before the actual start of the project, Christian Laskawi – Maya and RealFlow supervisor at Pictorion das Werk – and his colleagues in Düsseldorf began to prepare the effects and post production set up.
“We first created some RealFlow simulations for the waterfall, splashes, foam and sprays,” - Laskawi said.

"The import of RealFlow particle simulations into Maya is very comfortable,” - Laskawi said.

“Information about particle density, viscosity, pressure and several other parameters remains preserved and can be called as “per-particle” attributes inside Maya. Together with expression scripts, the particles can conveniently be influenced and also shaded."


"We had a highly optimized model of the BMW vehicle available, which we used in combinations with the 3D water simulations for the helicopter top-shot in the video,” Laskawi explained.
“Out of the high-resolution BMW model we built a low-resolution variant in Maya, which we facilitated as a collision object in RealFlow. I used the RealFlow Car-Wheel constraint for the simulation of the tire tracks."

Meanwhile, a team based in Munich under supervision of XSi expert Sebastian Weidner worked with XSi on shading the new BMW Hydrogen. Weidner also did the tracking, using PF Track and he also shaded the mesh calculated in RealFlow in XSi and Mentalray. Laskawi then took his turn and exported the entire scene with the car and camera as a FBX-scene, which was imported into RealFlow without problems.

"So we used Maya, XSi and RealFlow, exchanging geometry and camera data in the Autodesk FBX file format and the RealFlow SD format, and it was running great," - Laskawi said

The basic layer for the waterfall and the simulation for the dense water were rendered in XSi. The in RealFlow calculated meshes were then imported with the already prepared water shader applied to it. The shaded model of the car was used for the simulation of refractions and reflections in the water. In some shots the car is full CG, for example in the top shots, where the water wake coming off the car was created with a map in RealWave. HDR images took care of the light, mood and the environment of the advertisement. In the end, Laskawi decided to divide the entire, big RealFlow simulations into smaller simulations of maximum 1.5 million particles each to be able to handle the scenes better and improve performance. The simulations were later combined in compositing

While Laskawi and Weidner were working hard on the BWM project, the unofficial RealFlow forum was born (www.realflowforum.com).
“Thank God for that,” said Laskawi. “It was great to exchange information with the RealFlow-forum guys. A community like that really helps – a good inspiration.”

For the particle simulations, Pictorion das Werk set up a quad-core workstation with 64 bit Linux installed and a handful of dual-core machines with Windows XP with plenty of memory and RAM, which was disbursed with the several-million particle waterfall simulation that had to be simulated under a very tight deadline

Extremely happy with the final results of their hard work, Pictorian das Werk plans to use RealFlow again on future projects.

“We are currently doing research and development on our new film project, and we have run several tests with RealFlow Dynamic Simulations, collapsing and crashing buildings and creating water-object collisions,” said Laskawi continuing, “I just love this job.”
To see an R&D video click here
To see the final advertisement click here